2987 Commits

Author SHA1 Message Date
Eric Dumazet
0f5c0e0a4c net: sched: fix race condition in qdisc_graft()
commit ebda44da44f6f309d302522b049f43d6f829f7aa upstream.

We had one syzbot report [1] in syzbot queue for a while.
I was waiting for more occurrences and/or a repro but
Dmitry Vyukov spotted the issue right away.

<quoting Dmitry>
qdisc_graft() drops reference to qdisc in notify_and_destroy
while it's still assigned to dev->qdisc
</quoting>

Indeed, RCU rules are clear when replacing a data structure.
The visible pointer (dev->qdisc in this case) must be updated
to the new object _before_ RCU grace period is started
(qdisc_put(old) in this case).

[1]
BUG: KASAN: use-after-free in __tcf_qdisc_find.part.0+0xa3a/0xac0 net/sched/cls_api.c:1066
Read of size 4 at addr ffff88802065e038 by task syz-executor.4/21027

CPU: 0 PID: 21027 Comm: syz-executor.4 Not tainted 6.0.0-rc3-syzkaller-00363-g7726d4c3e60b #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/26/2022
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:88 [inline]
dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106
print_address_description mm/kasan/report.c:317 [inline]
print_report.cold+0x2ba/0x719 mm/kasan/report.c:433
kasan_report+0xb1/0x1e0 mm/kasan/report.c:495
__tcf_qdisc_find.part.0+0xa3a/0xac0 net/sched/cls_api.c:1066
__tcf_qdisc_find net/sched/cls_api.c:1051 [inline]
tc_new_tfilter+0x34f/0x2200 net/sched/cls_api.c:2018
rtnetlink_rcv_msg+0x955/0xca0 net/core/rtnetlink.c:6081
netlink_rcv_skb+0x153/0x420 net/netlink/af_netlink.c:2501
netlink_unicast_kernel net/netlink/af_netlink.c:1319 [inline]
netlink_unicast+0x543/0x7f0 net/netlink/af_netlink.c:1345
netlink_sendmsg+0x917/0xe10 net/netlink/af_netlink.c:1921
sock_sendmsg_nosec net/socket.c:714 [inline]
sock_sendmsg+0xcf/0x120 net/socket.c:734
____sys_sendmsg+0x6eb/0x810 net/socket.c:2482
___sys_sendmsg+0x110/0x1b0 net/socket.c:2536
__sys_sendmsg+0xf3/0x1c0 net/socket.c:2565
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x63/0xcd
RIP: 0033:0x7f5efaa89279
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f5efbc31168 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007f5efab9bf80 RCX: 00007f5efaa89279
RDX: 0000000000000000 RSI: 0000000020000140 RDI: 0000000000000005
RBP: 00007f5efaae32e9 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007f5efb0cfb1f R14: 00007f5efbc31300 R15: 0000000000022000
</TASK>

Allocated by task 21027:
kasan_save_stack+0x1e/0x40 mm/kasan/common.c:38
kasan_set_track mm/kasan/common.c:45 [inline]
set_alloc_info mm/kasan/common.c:437 [inline]
____kasan_kmalloc mm/kasan/common.c:516 [inline]
____kasan_kmalloc mm/kasan/common.c:475 [inline]
__kasan_kmalloc+0xa9/0xd0 mm/kasan/common.c:525
kmalloc_node include/linux/slab.h:623 [inline]
kzalloc_node include/linux/slab.h:744 [inline]
qdisc_alloc+0xb0/0xc50 net/sched/sch_generic.c:938
qdisc_create_dflt+0x71/0x4a0 net/sched/sch_generic.c:997
attach_one_default_qdisc net/sched/sch_generic.c:1152 [inline]
netdev_for_each_tx_queue include/linux/netdevice.h:2437 [inline]
attach_default_qdiscs net/sched/sch_generic.c:1170 [inline]
dev_activate+0x760/0xcd0 net/sched/sch_generic.c:1229
__dev_open+0x393/0x4d0 net/core/dev.c:1441
__dev_change_flags+0x583/0x750 net/core/dev.c:8556
rtnl_configure_link+0xee/0x240 net/core/rtnetlink.c:3189
rtnl_newlink_create net/core/rtnetlink.c:3371 [inline]
__rtnl_newlink+0x10b8/0x17e0 net/core/rtnetlink.c:3580
rtnl_newlink+0x64/0xa0 net/core/rtnetlink.c:3593
rtnetlink_rcv_msg+0x43a/0xca0 net/core/rtnetlink.c:6090
netlink_rcv_skb+0x153/0x420 net/netlink/af_netlink.c:2501
netlink_unicast_kernel net/netlink/af_netlink.c:1319 [inline]
netlink_unicast+0x543/0x7f0 net/netlink/af_netlink.c:1345
netlink_sendmsg+0x917/0xe10 net/netlink/af_netlink.c:1921
sock_sendmsg_nosec net/socket.c:714 [inline]
sock_sendmsg+0xcf/0x120 net/socket.c:734
____sys_sendmsg+0x6eb/0x810 net/socket.c:2482
___sys_sendmsg+0x110/0x1b0 net/socket.c:2536
__sys_sendmsg+0xf3/0x1c0 net/socket.c:2565
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x63/0xcd

Freed by task 21020:
kasan_save_stack+0x1e/0x40 mm/kasan/common.c:38
kasan_set_track+0x21/0x30 mm/kasan/common.c:45
kasan_set_free_info+0x20/0x30 mm/kasan/generic.c:370
____kasan_slab_free mm/kasan/common.c:367 [inline]
____kasan_slab_free+0x166/0x1c0 mm/kasan/common.c:329
kasan_slab_free include/linux/kasan.h:200 [inline]
slab_free_hook mm/slub.c:1754 [inline]
slab_free_freelist_hook+0x8b/0x1c0 mm/slub.c:1780
slab_free mm/slub.c:3534 [inline]
kfree+0xe2/0x580 mm/slub.c:4562
rcu_do_batch kernel/rcu/tree.c:2245 [inline]
rcu_core+0x7b5/0x1890 kernel/rcu/tree.c:2505
__do_softirq+0x1d3/0x9c6 kernel/softirq.c:571

Last potentially related work creation:
kasan_save_stack+0x1e/0x40 mm/kasan/common.c:38
__kasan_record_aux_stack+0xbe/0xd0 mm/kasan/generic.c:348
call_rcu+0x99/0x790 kernel/rcu/tree.c:2793
qdisc_put+0xcd/0xe0 net/sched/sch_generic.c:1083
notify_and_destroy net/sched/sch_api.c:1012 [inline]
qdisc_graft+0xeb1/0x1270 net/sched/sch_api.c:1084
tc_modify_qdisc+0xbb7/0x1a00 net/sched/sch_api.c:1671
rtnetlink_rcv_msg+0x43a/0xca0 net/core/rtnetlink.c:6090
netlink_rcv_skb+0x153/0x420 net/netlink/af_netlink.c:2501
netlink_unicast_kernel net/netlink/af_netlink.c:1319 [inline]
netlink_unicast+0x543/0x7f0 net/netlink/af_netlink.c:1345
netlink_sendmsg+0x917/0xe10 net/netlink/af_netlink.c:1921
sock_sendmsg_nosec net/socket.c:714 [inline]
sock_sendmsg+0xcf/0x120 net/socket.c:734
____sys_sendmsg+0x6eb/0x810 net/socket.c:2482
___sys_sendmsg+0x110/0x1b0 net/socket.c:2536
__sys_sendmsg+0xf3/0x1c0 net/socket.c:2565
do_syscall_x64 arch/x86/entry/common.c:50 [inline]
do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
entry_SYSCALL_64_after_hwframe+0x63/0xcd

Second to last potentially related work creation:
kasan_save_stack+0x1e/0x40 mm/kasan/common.c:38
__kasan_record_aux_stack+0xbe/0xd0 mm/kasan/generic.c:348
kvfree_call_rcu+0x74/0x940 kernel/rcu/tree.c:3322
neigh_destroy+0x431/0x630 net/core/neighbour.c:912
neigh_release include/net/neighbour.h:454 [inline]
neigh_cleanup_and_release+0x1f8/0x330 net/core/neighbour.c:103
neigh_del net/core/neighbour.c:225 [inline]
neigh_remove_one+0x37d/0x460 net/core/neighbour.c:246
neigh_forced_gc net/core/neighbour.c:276 [inline]
neigh_alloc net/core/neighbour.c:447 [inline]
___neigh_create+0x18b5/0x29a0 net/core/neighbour.c:642
ip6_finish_output2+0xfb8/0x1520 net/ipv6/ip6_output.c:125
__ip6_finish_output net/ipv6/ip6_output.c:195 [inline]
ip6_finish_output+0x690/0x1160 net/ipv6/ip6_output.c:206
NF_HOOK_COND include/linux/netfilter.h:296 [inline]
ip6_output+0x1ed/0x540 net/ipv6/ip6_output.c:227
dst_output include/net/dst.h:451 [inline]
NF_HOOK include/linux/netfilter.h:307 [inline]
NF_HOOK include/linux/netfilter.h:301 [inline]
mld_sendpack+0xa09/0xe70 net/ipv6/mcast.c:1820
mld_send_cr net/ipv6/mcast.c:2121 [inline]
mld_ifc_work+0x71c/0xdc0 net/ipv6/mcast.c:2653
process_one_work+0x991/0x1610 kernel/workqueue.c:2289
worker_thread+0x665/0x1080 kernel/workqueue.c:2436
kthread+0x2e4/0x3a0 kernel/kthread.c:376
ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:306

The buggy address belongs to the object at ffff88802065e000
which belongs to the cache kmalloc-1k of size 1024
The buggy address is located 56 bytes inside of
1024-byte region [ffff88802065e000, ffff88802065e400)

The buggy address belongs to the physical page:
page:ffffea0000819600 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x20658
head:ffffea0000819600 order:3 compound_mapcount:0 compound_pincount:0
flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff)
raw: 00fff00000010200 0000000000000000 dead000000000001 ffff888011841dc0
raw: 0000000000000000 0000000000100010 00000001ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 3, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 3523, tgid 3523 (sshd), ts 41495190986, free_ts 41417713212
prep_new_page mm/page_alloc.c:2532 [inline]
get_page_from_freelist+0x109b/0x2ce0 mm/page_alloc.c:4283
__alloc_pages+0x1c7/0x510 mm/page_alloc.c:5515
alloc_pages+0x1a6/0x270 mm/mempolicy.c:2270
alloc_slab_page mm/slub.c:1824 [inline]
allocate_slab+0x27e/0x3d0 mm/slub.c:1969
new_slab mm/slub.c:2029 [inline]
___slab_alloc+0x7f1/0xe10 mm/slub.c:3031
__slab_alloc.constprop.0+0x4d/0xa0 mm/slub.c:3118
slab_alloc_node mm/slub.c:3209 [inline]
__kmalloc_node_track_caller+0x2f2/0x380 mm/slub.c:4955
kmalloc_reserve net/core/skbuff.c:358 [inline]
__alloc_skb+0xd9/0x2f0 net/core/skbuff.c:430
alloc_skb_fclone include/linux/skbuff.h:1307 [inline]
tcp_stream_alloc_skb+0x38/0x580 net/ipv4/tcp.c:861
tcp_sendmsg_locked+0xc36/0x2f80 net/ipv4/tcp.c:1325
tcp_sendmsg+0x2b/0x40 net/ipv4/tcp.c:1483
inet_sendmsg+0x99/0xe0 net/ipv4/af_inet.c:819
sock_sendmsg_nosec net/socket.c:714 [inline]
sock_sendmsg+0xcf/0x120 net/socket.c:734
sock_write_iter+0x291/0x3d0 net/socket.c:1108
call_write_iter include/linux/fs.h:2187 [inline]
new_sync_write fs/read_write.c:491 [inline]
vfs_write+0x9e9/0xdd0 fs/read_write.c:578
ksys_write+0x1e8/0x250 fs/read_write.c:631
page last free stack trace:
reset_page_owner include/linux/page_owner.h:24 [inline]
free_pages_prepare mm/page_alloc.c:1449 [inline]
free_pcp_prepare+0x5e4/0xd20 mm/page_alloc.c:1499
free_unref_page_prepare mm/page_alloc.c:3380 [inline]
free_unref_page+0x19/0x4d0 mm/page_alloc.c:3476
__unfreeze_partials+0x17c/0x1a0 mm/slub.c:2548
qlink_free mm/kasan/quarantine.c:168 [inline]
qlist_free_all+0x6a/0x170 mm/kasan/quarantine.c:187
kasan_quarantine_reduce+0x180/0x200 mm/kasan/quarantine.c:294
__kasan_slab_alloc+0xa2/0xc0 mm/kasan/common.c:447
kasan_slab_alloc include/linux/kasan.h:224 [inline]
slab_post_alloc_hook mm/slab.h:727 [inline]
slab_alloc_node mm/slub.c:3243 [inline]
slab_alloc mm/slub.c:3251 [inline]
__kmem_cache_alloc_lru mm/slub.c:3258 [inline]
kmem_cache_alloc+0x267/0x3b0 mm/slub.c:3268
kmem_cache_zalloc include/linux/slab.h:723 [inline]
alloc_buffer_head+0x20/0x140 fs/buffer.c:2974
alloc_page_buffers+0x280/0x790 fs/buffer.c:829
create_empty_buffers+0x2c/0xee0 fs/buffer.c:1558
ext4_block_write_begin+0x1004/0x1530 fs/ext4/inode.c:1074
ext4_da_write_begin+0x422/0xae0 fs/ext4/inode.c:2996
generic_perform_write+0x246/0x560 mm/filemap.c:3738
ext4_buffered_write_iter+0x15b/0x460 fs/ext4/file.c:270
ext4_file_write_iter+0x44a/0x1660 fs/ext4/file.c:679
call_write_iter include/linux/fs.h:2187 [inline]
new_sync_write fs/read_write.c:491 [inline]
vfs_write+0x9e9/0xdd0 fs/read_write.c:578

Fixes: af356afa010f ("net_sched: reintroduce dev->qdisc for use by sch_api")
Reported-by: syzbot <syzkaller@googlegroups.com>
Diagnosed-by: Dmitry Vyukov <dvyukov@google.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Link: https://lore.kernel.org/r/20221018203258.2793282-1-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Zubin Mithra <zsm@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-04-05 11:16:46 +02:00
Eric Dumazet
22d95b5449 net_sched: add __rcu annotation to netdev->qdisc
commit 5891cd5ec46c2c2eb6427cb54d214b149635dd0e upstream.

syzbot found a data-race [1] which lead me to add __rcu
annotations to netdev->qdisc, and proper accessors
to get LOCKDEP support.

[1]
BUG: KCSAN: data-race in dev_activate / qdisc_lookup_rcu

write to 0xffff888168ad6410 of 8 bytes by task 13559 on cpu 1:
 attach_default_qdiscs net/sched/sch_generic.c:1167 [inline]
 dev_activate+0x2ed/0x8f0 net/sched/sch_generic.c:1221
 __dev_open+0x2e9/0x3a0 net/core/dev.c:1416
 __dev_change_flags+0x167/0x3f0 net/core/dev.c:8139
 rtnl_configure_link+0xc2/0x150 net/core/rtnetlink.c:3150
 __rtnl_newlink net/core/rtnetlink.c:3489 [inline]
 rtnl_newlink+0xf4d/0x13e0 net/core/rtnetlink.c:3529
 rtnetlink_rcv_msg+0x745/0x7e0 net/core/rtnetlink.c:5594
 netlink_rcv_skb+0x14e/0x250 net/netlink/af_netlink.c:2494
 rtnetlink_rcv+0x18/0x20 net/core/rtnetlink.c:5612
 netlink_unicast_kernel net/netlink/af_netlink.c:1317 [inline]
 netlink_unicast+0x602/0x6d0 net/netlink/af_netlink.c:1343
 netlink_sendmsg+0x728/0x850 net/netlink/af_netlink.c:1919
 sock_sendmsg_nosec net/socket.c:705 [inline]
 sock_sendmsg net/socket.c:725 [inline]
 ____sys_sendmsg+0x39a/0x510 net/socket.c:2413
 ___sys_sendmsg net/socket.c:2467 [inline]
 __sys_sendmsg+0x195/0x230 net/socket.c:2496
 __do_sys_sendmsg net/socket.c:2505 [inline]
 __se_sys_sendmsg net/socket.c:2503 [inline]
 __x64_sys_sendmsg+0x42/0x50 net/socket.c:2503
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x44/0xd0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae

read to 0xffff888168ad6410 of 8 bytes by task 13560 on cpu 0:
 qdisc_lookup_rcu+0x30/0x2e0 net/sched/sch_api.c:323
 __tcf_qdisc_find+0x74/0x3a0 net/sched/cls_api.c:1050
 tc_del_tfilter+0x1c7/0x1350 net/sched/cls_api.c:2211
 rtnetlink_rcv_msg+0x5ba/0x7e0 net/core/rtnetlink.c:5585
 netlink_rcv_skb+0x14e/0x250 net/netlink/af_netlink.c:2494
 rtnetlink_rcv+0x18/0x20 net/core/rtnetlink.c:5612
 netlink_unicast_kernel net/netlink/af_netlink.c:1317 [inline]
 netlink_unicast+0x602/0x6d0 net/netlink/af_netlink.c:1343
 netlink_sendmsg+0x728/0x850 net/netlink/af_netlink.c:1919
 sock_sendmsg_nosec net/socket.c:705 [inline]
 sock_sendmsg net/socket.c:725 [inline]
 ____sys_sendmsg+0x39a/0x510 net/socket.c:2413
 ___sys_sendmsg net/socket.c:2467 [inline]
 __sys_sendmsg+0x195/0x230 net/socket.c:2496
 __do_sys_sendmsg net/socket.c:2505 [inline]
 __se_sys_sendmsg net/socket.c:2503 [inline]
 __x64_sys_sendmsg+0x42/0x50 net/socket.c:2503
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x44/0xd0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae

value changed: 0xffffffff85dee080 -> 0xffff88815d96ec00

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 13560 Comm: syz-executor.2 Not tainted 5.17.0-rc3-syzkaller-00116-gf1baf68e1383-dirty #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011

Fixes: 470502de5bdb ("net: sched: unlock rules update API")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Vlad Buslov <vladbu@mellanox.com>
Reported-by: syzbot <syzkaller@googlegroups.com>
Cc: Jamal Hadi Salim <jhs@mojatatu.com>
Cc: Cong Wang <xiyou.wangcong@gmail.com>
Cc: Jiri Pirko <jiri@resnulli.us>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Zubin Mithra <zsm@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-04-05 11:16:46 +02:00
Pedro Tammela
dda4f0a424 net/sched: act_sample: fix action bind logic
[ Upstream commit 4a20056a49a1854966562241922f68197f950539 ]

The TC architecture allows filters and actions to be created independently.
In filters the user can reference action objects using:
tc action add action sample ... index 1
tc filter add ... action pedit index 1

In the current code for act_sample this is broken as it checks netlink
attributes for create/update before actually checking if we are binding to an
existing action.

tdc results:
1..29
ok 1 9784 - Add valid sample action with mandatory arguments
ok 2 5c91 - Add valid sample action with mandatory arguments and continue control action
ok 3 334b - Add valid sample action with mandatory arguments and drop control action
ok 4 da69 - Add valid sample action with mandatory arguments and reclassify control action
ok 5 13ce - Add valid sample action with mandatory arguments and pipe control action
ok 6 1886 - Add valid sample action with mandatory arguments and jump control action
ok 7 7571 - Add sample action with invalid rate
ok 8 b6d4 - Add sample action with mandatory arguments and invalid control action
ok 9 a874 - Add invalid sample action without mandatory arguments
ok 10 ac01 - Add invalid sample action without mandatory argument rate
ok 11 4203 - Add invalid sample action without mandatory argument group
ok 12 14a7 - Add invalid sample action without mandatory argument group
ok 13 8f2e - Add valid sample action with trunc argument
ok 14 45f8 - Add sample action with maximum rate argument
ok 15 ad0c - Add sample action with maximum trunc argument
ok 16 83a9 - Add sample action with maximum group argument
ok 17 ed27 - Add sample action with invalid rate argument
ok 18 2eae - Add sample action with invalid group argument
ok 19 6ff3 - Add sample action with invalid trunc size
ok 20 2b2a - Add sample action with invalid index
ok 21 dee2 - Add sample action with maximum allowed index
ok 22 560e - Add sample action with cookie
ok 23 704a - Replace existing sample action with new rate argument
ok 24 60eb - Replace existing sample action with new group argument
ok 25 2cce - Replace existing sample action with new trunc argument
ok 26 59d1 - Replace existing sample action with new control argument
ok 27 0a6e - Replace sample action with invalid goto chain control
ok 28 3872 - Delete sample action with valid index
ok 29 a394 - Delete sample action with invalid index

Fixes: 5c5670fae430 ("net/sched: Introduce sample tc action")
Reviewed-by: Jamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: Pedro Tammela <pctammela@mojatatu.com>
Reviewed-by: Simon Horman <simon.horman@corigine.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-03-11 16:44:12 +01:00
Jamal Hadi Salim
7a6fb69bbc net/sched: Retire tcindex classifier
commit 8c710f75256bb3cf05ac7b1672c82b92c43f3d28 upstream.

The tcindex classifier has served us well for about a quarter of a century
but has not been getting much TLC due to lack of known users. Most recently
it has become easy prey to syzkaller. For this reason, we are retiring it.

Signed-off-by: Jamal Hadi Salim <jhs@mojatatu.com>
Acked-by: Jiri Pirko <jiri@nvidia.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-03-11 16:44:07 +01:00
Vladimir Oltean
5d873a6c65 Revert "net/sched: taprio: make qdisc_leaf() see the per-netdev-queue pfifo child qdiscs"
commit af7b29b1deaac6da3bb7637f0e263dfab7bfc7a3 upstream.

taprio_attach() has this logic at the end, which should have been
removed with the blamed patch (which is now being reverted):

	/* access to the child qdiscs is not needed in offload mode */
	if (FULL_OFFLOAD_IS_ENABLED(q->flags)) {
		kfree(q->qdiscs);
		q->qdiscs = NULL;
	}

because otherwise, we make use of q->qdiscs[] even after this array was
deallocated, namely in taprio_leaf(). Therefore, whenever one would try
to attach a valid child qdisc to a fully offloaded taprio root, one
would immediately dereference a NULL pointer.

$ tc qdisc replace dev eno0 handle 8001: parent root taprio \
	num_tc 8 \
	map 0 1 2 3 4 5 6 7 \
	queues 1@0 1@1 1@2 1@3 1@4 1@5 1@6 1@7 \
	max-sdu 0 0 0 0 0 200 0 0 \
	base-time 200 \
	sched-entry S 80 20000 \
	sched-entry S a0 20000 \
	sched-entry S 5f 60000 \
	flags 2
$ max_frame_size=1500
$ data_rate_kbps=20000
$ port_transmit_rate_kbps=1000000
$ idleslope=$data_rate_kbps
$ sendslope=$(($idleslope - $port_transmit_rate_kbps))
$ locredit=$(($max_frame_size * $sendslope / $port_transmit_rate_kbps))
$ hicredit=$(($max_frame_size * $idleslope / $port_transmit_rate_kbps))
$ tc qdisc replace dev eno0 parent 8001:7 cbs \
	idleslope $idleslope \
	sendslope $sendslope \
	hicredit $hicredit \
	locredit $locredit \
	offload 0

Unable to handle kernel NULL pointer dereference at virtual address 0000000000000030
pc : taprio_leaf+0x28/0x40
lr : qdisc_leaf+0x3c/0x60
Call trace:
 taprio_leaf+0x28/0x40
 tc_modify_qdisc+0xf0/0x72c
 rtnetlink_rcv_msg+0x12c/0x390
 netlink_rcv_skb+0x5c/0x130
 rtnetlink_rcv+0x1c/0x2c

The solution is not as obvious as the problem. The code which deallocates
q->qdiscs[] is in fact copied and pasted from mqprio, which also
deallocates the array in mqprio_attach() and never uses it afterwards.

Therefore, the identical cleanup logic of priv->qdiscs[] that
mqprio_destroy() has is deceptive because it will never take place at
qdisc_destroy() time, but just at raw ops->destroy() time (otherwise
said, priv->qdiscs[] do not last for the entire lifetime of the mqprio
root), but rather, this is just the twisted way in which the Qdisc API
understands error path cleanup should be done (Qdisc_ops :: destroy() is
called even when Qdisc_ops :: init() never succeeded).

Side note, in fact this is also what the comment in mqprio_init() says:

	/* pre-allocate qdisc, attachment can't fail */

Or reworded, mqprio's priv->qdiscs[] scheme is only meant to serve as
data passing between Qdisc_ops :: init() and Qdisc_ops :: attach().

[ this comment was also copied and pasted into the initial taprio
  commit, even though taprio_attach() came way later ]

The problem is that taprio also makes extensive use of the q->qdiscs[]
array in the software fast path (taprio_enqueue() and taprio_dequeue()),
but it does not keep a reference of its own on q->qdiscs[i] (you'd think
that since it creates these Qdiscs, it holds the reference, but nope,
this is not completely true).

To understand the difference between taprio_destroy() and mqprio_destroy()
one must look before commit 13511704f8d7 ("net: taprio offload: enforce
qdisc to netdev queue mapping"), because that just muddied the waters.

In the "original" taprio design, taprio always attached itself (the root
Qdisc) to all netdev TX queues, so that dev_qdisc_enqueue() would go
through taprio_enqueue().

It also called qdisc_refcount_inc() on itself for as many times as there
were netdev TX queues, in order to counter-balance what tc_get_qdisc()
does when destroying a Qdisc (simplified for brevity below):

	if (n->nlmsg_type == RTM_DELQDISC)
		err = qdisc_graft(dev, parent=NULL, new=NULL, q, extack);

qdisc_graft(where "new" is NULL so this deletes the Qdisc):

	for (i = 0; i < num_q; i++) {
		struct netdev_queue *dev_queue;

		dev_queue = netdev_get_tx_queue(dev, i);

		old = dev_graft_qdisc(dev_queue, new);
		if (new && i > 0)
			qdisc_refcount_inc(new);

		qdisc_put(old);
		~~~~~~~~~~~~~~
		this decrements taprio's refcount once for each TX queue
	}

	notify_and_destroy(net, skb, n, classid,
			   rtnl_dereference(dev->qdisc), new);
			   ~~~~~~~~~~~~~~~~~~~~~~~~~~~~
			   and this finally decrements it to zero,
			   making qdisc_put() call qdisc_destroy()

The q->qdiscs[] created using qdisc_create_dflt() (or their
replacements, if taprio_graft() was ever to get called) were then
privately freed by taprio_destroy().

This is still what is happening after commit 13511704f8d7 ("net: taprio
offload: enforce qdisc to netdev queue mapping"), but only for software
mode.

In full offload mode, the per-txq "qdisc_put(old)" calls from
qdisc_graft() now deallocate the child Qdiscs rather than decrement
taprio's refcount. So when notify_and_destroy(taprio) finally calls
taprio_destroy(), the difference is that the child Qdiscs were already
deallocated.

And this is exactly why the taprio_attach() comment "access to the child
qdiscs is not needed in offload mode" is deceptive too. Not only the
q->qdiscs[] array is not needed, but it is also necessary to get rid of
it as soon as possible, because otherwise, we will also call qdisc_put()
on the child Qdiscs in qdisc_destroy() -> taprio_destroy(), and this
will cause a nasty use-after-free/refcount-saturate/whatever.

In short, the problem is that since the blamed commit, taprio_leaf()
needs q->qdiscs[] to not be freed by taprio_attach(), while qdisc_destroy()
-> taprio_destroy() does need q->qdiscs[] to be freed by taprio_attach()
for full offload. Fixing one problem triggers the other.

All of this can be solved by making taprio keep its q->qdiscs[i] with a
refcount elevated at 2 (in offloaded mode where they are attached to the
netdev TX queues), both in taprio_attach() and in taprio_graft(). The
generic qdisc_graft() would just decrement the child qdiscs' refcounts
to 1, and taprio_destroy() would give them the final coup de grace.

However the rabbit hole of changes is getting quite deep, and the
complexity increases. The blamed commit was supposed to be a bug fix in
the first place, and the bug it addressed is not so significant so as to
justify further rework in stable trees. So I'd rather just revert it.
I don't know enough about multi-queue Qdisc design to make a proper
judgement right now regarding what is/isn't idiomatic use of Qdisc
concepts in taprio. I will try to study the problem more and come with a
different solution in net-next.

Fixes: 1461d212ab27 ("net/sched: taprio: make qdisc_leaf() see the per-netdev-queue pfifo child qdiscs")
Reported-by: Muhammad Husaini Zulkifli <muhammad.husaini.zulkifli@intel.com>
Reported-by: Vinicius Costa Gomes <vinicius.gomes@intel.com>
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: Vinicius Costa Gomes <vinicius.gomes@intel.com>
Link: https://lore.kernel.org/r/20221004220100.1650558-1-vladimir.oltean@nxp.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-02-25 11:53:27 +01:00
Dan Carpenter
7519069f1f net: sched: sch: Fix off by one in htb_activate_prios()
commit 9cec2aaffe969f2a3e18b5ec105fc20bb908e475 upstream.

The > needs be >= to prevent an out of bounds access.

Fixes: de5ca4c3852f ("net: sched: sch: Bounds check priority")
Signed-off-by: Dan Carpenter <error27@gmail.com>
Reviewed-by: Simon Horman <simon.horman@corigine.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/r/Y+D+KN18FQI2DKLq@kili
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-02-22 12:50:42 +01:00
Kees Cook
fbe71c5dac net: sched: sch: Bounds check priority
[ Upstream commit de5ca4c3852f896cacac2bf259597aab5e17d9e3 ]

Nothing was explicitly bounds checking the priority index used to access
clpriop[]. WARN and bail out early if it's pathological. Seen with GCC 13:

../net/sched/sch_htb.c: In function 'htb_activate_prios':
../net/sched/sch_htb.c:437:44: warning: array subscript [0, 31] is outside array bounds of 'struct htb_prio[8]' [-Warray-bounds=]
  437 |                         if (p->inner.clprio[prio].feed.rb_node)
      |                             ~~~~~~~~~~~~~~~^~~~~~
../net/sched/sch_htb.c:131:41: note: while referencing 'clprio'
  131 |                         struct htb_prio clprio[TC_HTB_NUMPRIO];
      |                                         ^~~~~~

Cc: Jamal Hadi Salim <jhs@mojatatu.com>
Cc: Cong Wang <xiyou.wangcong@gmail.com>
Cc: Jiri Pirko <jiri@resnulli.us>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: Eric Dumazet <edumazet@google.com>
Cc: Jakub Kicinski <kuba@kernel.org>
Cc: Paolo Abeni <pabeni@redhat.com>
Cc: netdev@vger.kernel.org
Signed-off-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Simon Horman <simon.horman@corigine.com>
Reviewed-by: Cong Wang <cong.wang@bytedance.com>
Link: https://lore.kernel.org/r/20230127224036.never.561-kees@kernel.org
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-02-22 12:50:34 +01:00
Eric Dumazet
dae05cd371 net/sched: sch_taprio: do not schedule in taprio_reset()
[ Upstream commit ea4fdbaa2f7798cb25adbe4fd52ffc6356f097bb ]

As reported by syzbot and hinted by Vinicius, I should not have added
a qdisc_synchronize() call in taprio_reset()

taprio_reset() can be called with qdisc spinlock held (and BH disabled)
as shown in included syzbot report [1].

Only taprio_destroy() needed this synchronization, as explained
in the blamed commit changelog.

[1]

BUG: scheduling while atomic: syz-executor150/5091/0x00000202
2 locks held by syz-executor150/5091:
Modules linked in:
Preemption disabled at:
[<0000000000000000>] 0x0
Kernel panic - not syncing: scheduling while atomic: panic_on_warn set ...
CPU: 1 PID: 5091 Comm: syz-executor150 Not tainted 6.2.0-rc3-syzkaller-00219-g010a74f52203 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/12/2023
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:88 [inline]
dump_stack_lvl+0xd1/0x138 lib/dump_stack.c:106
panic+0x2cc/0x626 kernel/panic.c:318
check_panic_on_warn.cold+0x19/0x35 kernel/panic.c:238
__schedule_bug.cold+0xd5/0xfe kernel/sched/core.c:5836
schedule_debug kernel/sched/core.c:5865 [inline]
__schedule+0x34e4/0x5450 kernel/sched/core.c:6500
schedule+0xde/0x1b0 kernel/sched/core.c:6682
schedule_timeout+0x14e/0x2a0 kernel/time/timer.c:2167
schedule_timeout_uninterruptible kernel/time/timer.c:2201 [inline]
msleep+0xb6/0x100 kernel/time/timer.c:2322
qdisc_synchronize include/net/sch_generic.h:1295 [inline]
taprio_reset+0x93/0x270 net/sched/sch_taprio.c:1703
qdisc_reset+0x10c/0x770 net/sched/sch_generic.c:1022
dev_reset_queue+0x92/0x130 net/sched/sch_generic.c:1285
netdev_for_each_tx_queue include/linux/netdevice.h:2464 [inline]
dev_deactivate_many+0x36d/0x9f0 net/sched/sch_generic.c:1351
dev_deactivate+0xed/0x1b0 net/sched/sch_generic.c:1374
qdisc_graft+0xe4a/0x1380 net/sched/sch_api.c:1080
tc_modify_qdisc+0xb6b/0x19a0 net/sched/sch_api.c:1689
rtnetlink_rcv_msg+0x43e/0xca0 net/core/rtnetlink.c:6141
netlink_rcv_skb+0x165/0x440 net/netlink/af_netlink.c:2564
netlink_unicast_kernel net/netlink/af_netlink.c:1330 [inline]
netlink_unicast+0x547/0x7f0 net/netlink/af_netlink.c:1356
netlink_sendmsg+0x91b/0xe10 net/netlink/af_netlink.c:1932
sock_sendmsg_nosec net/socket.c:714 [inline]
sock_sendmsg+0xd3/0x120 net/socket.c:734
____sys_sendmsg+0x712/0x8c0 net/socket.c:2476
___sys_sendmsg+0x110/0x1b0 net/socket.c:2530
__sys_sendmsg+0xf7/0x1c0 net/socket.c:2559
do_syscall_x64 arch/x86/entry/common.c:50 [inline]

Fixes: 3a415d59c1db ("net/sched: sch_taprio: fix possible use-after-free")
Link: https://lore.kernel.org/netdev/167387581653.2747.13878941339893288655.git-patchwork-notify@kernel.org/T/
Reported-by: syzbot <syzkaller@googlegroups.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Vinicius Costa Gomes <vinicius.gomes@intel.com>
Link: https://lore.kernel.org/r/20230123084552.574396-1-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-02-06 07:52:46 +01:00
Eric Dumazet
1200388a0b net/sched: sch_taprio: fix possible use-after-free
[ Upstream commit 3a415d59c1dbec9d772dbfab2d2520d98360caae ]

syzbot reported a nasty crash [1] in net_tx_action() which
made little sense until we got a repro.

This repro installs a taprio qdisc, but providing an
invalid TCA_RATE attribute.

qdisc_create() has to destroy the just initialized
taprio qdisc, and taprio_destroy() is called.

However, the hrtimer used by taprio had already fired,
therefore advance_sched() called __netif_schedule().

Then net_tx_action was trying to use a destroyed qdisc.

We can not undo the __netif_schedule(), so we must wait
until one cpu serviced the qdisc before we can proceed.

Many thanks to Alexander Potapenko for his help.

[1]
BUG: KMSAN: uninit-value in queued_spin_trylock include/asm-generic/qspinlock.h:94 [inline]
BUG: KMSAN: uninit-value in do_raw_spin_trylock include/linux/spinlock.h:191 [inline]
BUG: KMSAN: uninit-value in __raw_spin_trylock include/linux/spinlock_api_smp.h:89 [inline]
BUG: KMSAN: uninit-value in _raw_spin_trylock+0x92/0xa0 kernel/locking/spinlock.c:138
 queued_spin_trylock include/asm-generic/qspinlock.h:94 [inline]
 do_raw_spin_trylock include/linux/spinlock.h:191 [inline]
 __raw_spin_trylock include/linux/spinlock_api_smp.h:89 [inline]
 _raw_spin_trylock+0x92/0xa0 kernel/locking/spinlock.c:138
 spin_trylock include/linux/spinlock.h:359 [inline]
 qdisc_run_begin include/net/sch_generic.h:187 [inline]
 qdisc_run+0xee/0x540 include/net/pkt_sched.h:125
 net_tx_action+0x77c/0x9a0 net/core/dev.c:5086
 __do_softirq+0x1cc/0x7fb kernel/softirq.c:571
 run_ksoftirqd+0x2c/0x50 kernel/softirq.c:934
 smpboot_thread_fn+0x554/0x9f0 kernel/smpboot.c:164
 kthread+0x31b/0x430 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30

Uninit was created at:
 slab_post_alloc_hook mm/slab.h:732 [inline]
 slab_alloc_node mm/slub.c:3258 [inline]
 __kmalloc_node_track_caller+0x814/0x1250 mm/slub.c:4970
 kmalloc_reserve net/core/skbuff.c:358 [inline]
 __alloc_skb+0x346/0xcf0 net/core/skbuff.c:430
 alloc_skb include/linux/skbuff.h:1257 [inline]
 nlmsg_new include/net/netlink.h:953 [inline]
 netlink_ack+0x5f3/0x12b0 net/netlink/af_netlink.c:2436
 netlink_rcv_skb+0x55d/0x6c0 net/netlink/af_netlink.c:2507
 rtnetlink_rcv+0x30/0x40 net/core/rtnetlink.c:6108
 netlink_unicast_kernel net/netlink/af_netlink.c:1319 [inline]
 netlink_unicast+0xf3b/0x1270 net/netlink/af_netlink.c:1345
 netlink_sendmsg+0x1288/0x1440 net/netlink/af_netlink.c:1921
 sock_sendmsg_nosec net/socket.c:714 [inline]
 sock_sendmsg net/socket.c:734 [inline]
 ____sys_sendmsg+0xabc/0xe90 net/socket.c:2482
 ___sys_sendmsg+0x2a1/0x3f0 net/socket.c:2536
 __sys_sendmsg net/socket.c:2565 [inline]
 __do_sys_sendmsg net/socket.c:2574 [inline]
 __se_sys_sendmsg net/socket.c:2572 [inline]
 __x64_sys_sendmsg+0x367/0x540 net/socket.c:2572
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

CPU: 0 PID: 13 Comm: ksoftirqd/0 Not tainted 6.0.0-rc2-syzkaller-47461-gac3859c02d7f #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/22/2022

Fixes: 5a781ccbd19e ("tc: Add support for configuring the taprio scheduler")
Reported-by: syzbot <syzkaller@googlegroups.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Alexander Potapenko <glider@google.com>
Cc: Vinicius Costa Gomes <vinicius.gomes@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-02-06 07:52:37 +01:00
Ido Schimmel
2b157c3c5d net/sched: act_mpls: Fix warning during failed attribute validation
[ Upstream commit 9e17f99220d111ea031b44153fdfe364b0024ff2 ]

The 'TCA_MPLS_LABEL' attribute is of 'NLA_U32' type, but has a
validation type of 'NLA_VALIDATE_FUNCTION'. This is an invalid
combination according to the comment above 'struct nla_policy':

"
Meaning of `validate' field, use via NLA_POLICY_VALIDATE_FN:
   NLA_BINARY           Validation function called for the attribute.
   All other            Unused - but note that it's a union
"

This can trigger the warning [1] in nla_get_range_unsigned() when
validation of the attribute fails. Despite being of 'NLA_U32' type, the
associated 'min'/'max' fields in the policy are negative as they are
aliased by the 'validate' field.

Fix by changing the attribute type to 'NLA_BINARY' which is consistent
with the above comment and all other users of NLA_POLICY_VALIDATE_FN().
As a result, move the length validation to the validation function.

No regressions in MPLS tests:

 # ./tdc.py -f tc-tests/actions/mpls.json
 [...]
 # echo $?
 0

[1]
WARNING: CPU: 0 PID: 17743 at lib/nlattr.c:118
nla_get_range_unsigned+0x1d8/0x1e0 lib/nlattr.c:117
Modules linked in:
CPU: 0 PID: 17743 Comm: syz-executor.0 Not tainted 6.1.0-rc8 #3
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS
rel-1.13.0-48-gd9c812dda519-prebuilt.qemu.org 04/01/2014
RIP: 0010:nla_get_range_unsigned+0x1d8/0x1e0 lib/nlattr.c:117
[...]
Call Trace:
 <TASK>
 __netlink_policy_dump_write_attr+0x23d/0x990 net/netlink/policy.c:310
 netlink_policy_dump_write_attr+0x22/0x30 net/netlink/policy.c:411
 netlink_ack_tlv_fill net/netlink/af_netlink.c:2454 [inline]
 netlink_ack+0x546/0x760 net/netlink/af_netlink.c:2506
 netlink_rcv_skb+0x1b7/0x240 net/netlink/af_netlink.c:2546
 rtnetlink_rcv+0x18/0x20 net/core/rtnetlink.c:6109
 netlink_unicast_kernel net/netlink/af_netlink.c:1319 [inline]
 netlink_unicast+0x5e9/0x6b0 net/netlink/af_netlink.c:1345
 netlink_sendmsg+0x739/0x860 net/netlink/af_netlink.c:1921
 sock_sendmsg_nosec net/socket.c:714 [inline]
 sock_sendmsg net/socket.c:734 [inline]
 ____sys_sendmsg+0x38f/0x500 net/socket.c:2482
 ___sys_sendmsg net/socket.c:2536 [inline]
 __sys_sendmsg+0x197/0x230 net/socket.c:2565
 __do_sys_sendmsg net/socket.c:2574 [inline]
 __se_sys_sendmsg net/socket.c:2572 [inline]
 __x64_sys_sendmsg+0x42/0x50 net/socket.c:2572
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x2b/0x70 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x63/0xcd

Link: https://lore.kernel.org/netdev/CAO4mrfdmjvRUNbDyP0R03_DrD_eFCLCguz6OxZ2TYRSv0K9gxA@mail.gmail.com/
Fixes: 2a2ea50870ba ("net: sched: add mpls manipulation actions to TC")
Reported-by: Wei Chen <harperchen1110@gmail.com>
Tested-by: Wei Chen <harperchen1110@gmail.com>
Signed-off-by: Ido Schimmel <idosch@nvidia.com>
Reviewed-by: Alexander Duyck <alexanderduyck@fb.com>
Link: https://lore.kernel.org/r/20230107171004.608436-1-idosch@nvidia.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-01-18 11:42:04 +01:00
Frederick Lawler
9b83ec63d0 net: sched: disallow noqueue for qdisc classes
commit 96398560f26aa07e8f2969d73c8197e6a6d10407 upstream.

While experimenting with applying noqueue to a classful queue discipline,
we discovered a NULL pointer dereference in the __dev_queue_xmit()
path that generates a kernel OOPS:

    # dev=enp0s5
    # tc qdisc replace dev $dev root handle 1: htb default 1
    # tc class add dev $dev parent 1: classid 1:1 htb rate 10mbit
    # tc qdisc add dev $dev parent 1:1 handle 10: noqueue
    # ping -I $dev -w 1 -c 1 1.1.1.1

[    2.172856] BUG: kernel NULL pointer dereference, address: 0000000000000000
[    2.173217] #PF: supervisor instruction fetch in kernel mode
...
[    2.178451] Call Trace:
[    2.178577]  <TASK>
[    2.178686]  htb_enqueue+0x1c8/0x370
[    2.178880]  dev_qdisc_enqueue+0x15/0x90
[    2.179093]  __dev_queue_xmit+0x798/0xd00
[    2.179305]  ? _raw_write_lock_bh+0xe/0x30
[    2.179522]  ? __local_bh_enable_ip+0x32/0x70
[    2.179759]  ? ___neigh_create+0x610/0x840
[    2.179968]  ? eth_header+0x21/0xc0
[    2.180144]  ip_finish_output2+0x15e/0x4f0
[    2.180348]  ? dst_output+0x30/0x30
[    2.180525]  ip_push_pending_frames+0x9d/0xb0
[    2.180739]  raw_sendmsg+0x601/0xcb0
[    2.180916]  ? _raw_spin_trylock+0xe/0x50
[    2.181112]  ? _raw_spin_unlock_irqrestore+0x16/0x30
[    2.181354]  ? get_page_from_freelist+0xcd6/0xdf0
[    2.181594]  ? sock_sendmsg+0x56/0x60
[    2.181781]  sock_sendmsg+0x56/0x60
[    2.181958]  __sys_sendto+0xf7/0x160
[    2.182139]  ? handle_mm_fault+0x6e/0x1d0
[    2.182366]  ? do_user_addr_fault+0x1e1/0x660
[    2.182627]  __x64_sys_sendto+0x1b/0x30
[    2.182881]  do_syscall_64+0x38/0x90
[    2.183085]  entry_SYSCALL_64_after_hwframe+0x63/0xcd
...
[    2.187402]  </TASK>

Previously in commit d66d6c3152e8 ("net: sched: register noqueue
qdisc"), NULL was set for the noqueue discipline on noqueue init
so that __dev_queue_xmit() falls through for the noqueue case. This
also sets a bypass of the enqueue NULL check in the
register_qdisc() function for the struct noqueue_disc_ops.

Classful queue disciplines make it past the NULL check in
__dev_queue_xmit() because the discipline is set to htb (in this case),
and then in the call to __dev_xmit_skb(), it calls into htb_enqueue()
which grabs a leaf node for a class and then calls qdisc_enqueue() by
passing in a queue discipline which assumes ->enqueue() is not set to NULL.

Fix this by not allowing classes to be assigned to the noqueue
discipline. Linux TC Notes states that classes cannot be set to
the noqueue discipline. [1] Let's enforce that here.

Links:
1. https://linux-tc-notes.sourceforge.net/tc/doc/sch_noqueue.txt

Fixes: d66d6c3152e8 ("net: sched: register noqueue qdisc")
Cc: stable@vger.kernel.org
Signed-off-by: Frederick Lawler <fred@cloudflare.com>
Reviewed-by: Jakub Sitnicki <jakub@cloudflare.com>
Link: https://lore.kernel.org/r/20230109163906.706000-1-fred@cloudflare.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-01-18 11:42:00 +01:00
Jamal Hadi Salim
6b17b84634 net: sched: cbq: dont intepret cls results when asked to drop
[ Upstream commit caa4b35b4317d5147b3ab0fbdc9c075c7d2e9c12 ]

If asked to drop a packet via TC_ACT_SHOT it is unsafe to assume that
res.class contains a valid pointer

Sample splat reported by Kyle Zeng

[    5.405624] 0: reclassify loop, rule prio 0, protocol 800
[    5.406326] ==================================================================
[    5.407240] BUG: KASAN: slab-out-of-bounds in cbq_enqueue+0x54b/0xea0
[    5.407987] Read of size 1 at addr ffff88800e3122aa by task poc/299
[    5.408731]
[    5.408897] CPU: 0 PID: 299 Comm: poc Not tainted 5.10.155+ #15
[    5.409516] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996),
BIOS 1.15.0-1 04/01/2014
[    5.410439] Call Trace:
[    5.410764]  dump_stack+0x87/0xcd
[    5.411153]  print_address_description+0x7a/0x6b0
[    5.411687]  ? vprintk_func+0xb9/0xc0
[    5.411905]  ? printk+0x76/0x96
[    5.412110]  ? cbq_enqueue+0x54b/0xea0
[    5.412323]  kasan_report+0x17d/0x220
[    5.412591]  ? cbq_enqueue+0x54b/0xea0
[    5.412803]  __asan_report_load1_noabort+0x10/0x20
[    5.413119]  cbq_enqueue+0x54b/0xea0
[    5.413400]  ? __kasan_check_write+0x10/0x20
[    5.413679]  __dev_queue_xmit+0x9c0/0x1db0
[    5.413922]  dev_queue_xmit+0xc/0x10
[    5.414136]  ip_finish_output2+0x8bc/0xcd0
[    5.414436]  __ip_finish_output+0x472/0x7a0
[    5.414692]  ip_finish_output+0x5c/0x190
[    5.414940]  ip_output+0x2d8/0x3c0
[    5.415150]  ? ip_mc_finish_output+0x320/0x320
[    5.415429]  __ip_queue_xmit+0x753/0x1760
[    5.415664]  ip_queue_xmit+0x47/0x60
[    5.415874]  __tcp_transmit_skb+0x1ef9/0x34c0
[    5.416129]  tcp_connect+0x1f5e/0x4cb0
[    5.416347]  tcp_v4_connect+0xc8d/0x18c0
[    5.416577]  __inet_stream_connect+0x1ae/0xb40
[    5.416836]  ? local_bh_enable+0x11/0x20
[    5.417066]  ? lock_sock_nested+0x175/0x1d0
[    5.417309]  inet_stream_connect+0x5d/0x90
[    5.417548]  ? __inet_stream_connect+0xb40/0xb40
[    5.417817]  __sys_connect+0x260/0x2b0
[    5.418037]  __x64_sys_connect+0x76/0x80
[    5.418267]  do_syscall_64+0x31/0x50
[    5.418477]  entry_SYSCALL_64_after_hwframe+0x61/0xc6
[    5.418770] RIP: 0033:0x473bb7
[    5.418952] Code: 64 89 01 48 83 c8 ff c3 66 2e 0f 1f 84 00 00 00
00 00 90 f3 0f 1e fa 64 8b 04 25 18 00 00 00 85 c0 75 10 b8 2a 00 00
00 0f 05 <48> 3d 00 f0 ff ff 77 51 c3 48 83 ec 18 89 54 24 0c 48 89 34
24 89
[    5.420046] RSP: 002b:00007fffd20eb0f8 EFLAGS: 00000246 ORIG_RAX:
000000000000002a
[    5.420472] RAX: ffffffffffffffda RBX: 00007fffd20eb578 RCX: 0000000000473bb7
[    5.420872] RDX: 0000000000000010 RSI: 00007fffd20eb110 RDI: 0000000000000007
[    5.421271] RBP: 00007fffd20eb150 R08: 0000000000000001 R09: 0000000000000004
[    5.421671] R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000001
[    5.422071] R13: 00007fffd20eb568 R14: 00000000004fc740 R15: 0000000000000002
[    5.422471]
[    5.422562] Allocated by task 299:
[    5.422782]  __kasan_kmalloc+0x12d/0x160
[    5.423007]  kasan_kmalloc+0x5/0x10
[    5.423208]  kmem_cache_alloc_trace+0x201/0x2e0
[    5.423492]  tcf_proto_create+0x65/0x290
[    5.423721]  tc_new_tfilter+0x137e/0x1830
[    5.423957]  rtnetlink_rcv_msg+0x730/0x9f0
[    5.424197]  netlink_rcv_skb+0x166/0x300
[    5.424428]  rtnetlink_rcv+0x11/0x20
[    5.424639]  netlink_unicast+0x673/0x860
[    5.424870]  netlink_sendmsg+0x6af/0x9f0
[    5.425100]  __sys_sendto+0x58d/0x5a0
[    5.425315]  __x64_sys_sendto+0xda/0xf0
[    5.425539]  do_syscall_64+0x31/0x50
[    5.425764]  entry_SYSCALL_64_after_hwframe+0x61/0xc6
[    5.426065]
[    5.426157] The buggy address belongs to the object at ffff88800e312200
[    5.426157]  which belongs to the cache kmalloc-128 of size 128
[    5.426955] The buggy address is located 42 bytes to the right of
[    5.426955]  128-byte region [ffff88800e312200, ffff88800e312280)
[    5.427688] The buggy address belongs to the page:
[    5.427992] page:000000009875fabc refcount:1 mapcount:0
mapping:0000000000000000 index:0x0 pfn:0xe312
[    5.428562] flags: 0x100000000000200(slab)
[    5.428812] raw: 0100000000000200 dead000000000100 dead000000000122
ffff888007843680
[    5.429325] raw: 0000000000000000 0000000000100010 00000001ffffffff
ffff88800e312401
[    5.429875] page dumped because: kasan: bad access detected
[    5.430214] page->mem_cgroup:ffff88800e312401
[    5.430471]
[    5.430564] Memory state around the buggy address:
[    5.430846]  ffff88800e312180: fc fc fc fc fc fc fc fc fc fc fc fc
fc fc fc fc
[    5.431267]  ffff88800e312200: 00 00 00 00 00 00 00 00 00 00 00 00
00 00 00 fc
[    5.431705] >ffff88800e312280: fc fc fc fc fc fc fc fc fc fc fc fc
fc fc fc fc
[    5.432123]                                   ^
[    5.432391]  ffff88800e312300: 00 00 00 00 00 00 00 00 00 00 00 00
00 00 00 fc
[    5.432810]  ffff88800e312380: fc fc fc fc fc fc fc fc fc fc fc fc
fc fc fc fc
[    5.433229] ==================================================================
[    5.433648] Disabling lock debugging due to kernel taint

Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Reported-by: Kyle Zeng <zengyhkyle@gmail.com>
Signed-off-by: Jamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-01-18 11:41:58 +01:00
Jamal Hadi Salim
63e469cb54 net: sched: atm: dont intepret cls results when asked to drop
[ Upstream commit a2965c7be0522eaa18808684b7b82b248515511b ]

If asked to drop a packet via TC_ACT_SHOT it is unsafe to assume
res.class contains a valid pointer
Fixes: b0188d4dbe5f ("[NET_SCHED]: sch_atm: Lindent")

Signed-off-by: Jamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-01-18 11:41:58 +01:00
Hawkins Jiawei
55ac68b53f net: sched: fix memory leak in tcindex_set_parms
[ Upstream commit 399ab7fe0fa0d846881685fd4e57e9a8ef7559f7 ]

Syzkaller reports a memory leak as follows:
====================================
BUG: memory leak
unreferenced object 0xffff88810c287f00 (size 256):
  comm "syz-executor105", pid 3600, jiffies 4294943292 (age 12.990s)
  hex dump (first 32 bytes):
    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
    00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00  ................
  backtrace:
    [<ffffffff814cf9f0>] kmalloc_trace+0x20/0x90 mm/slab_common.c:1046
    [<ffffffff839c9e07>] kmalloc include/linux/slab.h:576 [inline]
    [<ffffffff839c9e07>] kmalloc_array include/linux/slab.h:627 [inline]
    [<ffffffff839c9e07>] kcalloc include/linux/slab.h:659 [inline]
    [<ffffffff839c9e07>] tcf_exts_init include/net/pkt_cls.h:250 [inline]
    [<ffffffff839c9e07>] tcindex_set_parms+0xa7/0xbe0 net/sched/cls_tcindex.c:342
    [<ffffffff839caa1f>] tcindex_change+0xdf/0x120 net/sched/cls_tcindex.c:553
    [<ffffffff8394db62>] tc_new_tfilter+0x4f2/0x1100 net/sched/cls_api.c:2147
    [<ffffffff8389e91c>] rtnetlink_rcv_msg+0x4dc/0x5d0 net/core/rtnetlink.c:6082
    [<ffffffff839eba67>] netlink_rcv_skb+0x87/0x1d0 net/netlink/af_netlink.c:2540
    [<ffffffff839eab87>] netlink_unicast_kernel net/netlink/af_netlink.c:1319 [inline]
    [<ffffffff839eab87>] netlink_unicast+0x397/0x4c0 net/netlink/af_netlink.c:1345
    [<ffffffff839eb046>] netlink_sendmsg+0x396/0x710 net/netlink/af_netlink.c:1921
    [<ffffffff8383e796>] sock_sendmsg_nosec net/socket.c:714 [inline]
    [<ffffffff8383e796>] sock_sendmsg+0x56/0x80 net/socket.c:734
    [<ffffffff8383eb08>] ____sys_sendmsg+0x178/0x410 net/socket.c:2482
    [<ffffffff83843678>] ___sys_sendmsg+0xa8/0x110 net/socket.c:2536
    [<ffffffff838439c5>] __sys_sendmmsg+0x105/0x330 net/socket.c:2622
    [<ffffffff83843c14>] __do_sys_sendmmsg net/socket.c:2651 [inline]
    [<ffffffff83843c14>] __se_sys_sendmmsg net/socket.c:2648 [inline]
    [<ffffffff83843c14>] __x64_sys_sendmmsg+0x24/0x30 net/socket.c:2648
    [<ffffffff84605fd5>] do_syscall_x64 arch/x86/entry/common.c:50 [inline]
    [<ffffffff84605fd5>] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
    [<ffffffff84800087>] entry_SYSCALL_64_after_hwframe+0x63/0xcd
====================================

Kernel uses tcindex_change() to change an existing
filter properties.

Yet the problem is that, during the process of changing,
if `old_r` is retrieved from `p->perfect`, then
kernel uses tcindex_alloc_perfect_hash() to newly
allocate filter results, uses tcindex_filter_result_init()
to clear the old filter result, without destroying
its tcf_exts structure, which triggers the above memory leak.

To be more specific, there are only two source for the `old_r`,
according to the tcindex_lookup(). `old_r` is retrieved from
`p->perfect`, or `old_r` is retrieved from `p->h`.

  * If `old_r` is retrieved from `p->perfect`, kernel uses
tcindex_alloc_perfect_hash() to newly allocate the
filter results. Then `r` is assigned with `cp->perfect + handle`,
which is newly allocated. So condition `old_r && old_r != r` is
true in this situation, and kernel uses tcindex_filter_result_init()
to clear the old filter result, without destroying
its tcf_exts structure

  * If `old_r` is retrieved from `p->h`, then `p->perfect` is NULL
according to the tcindex_lookup(). Considering that `cp->h`
is directly copied from `p->h` and `p->perfect` is NULL,
`r` is assigned with `tcindex_lookup(cp, handle)`, whose value
should be the same as `old_r`, so condition `old_r && old_r != r`
is false in this situation, kernel ignores using
tcindex_filter_result_init() to clear the old filter result.

So only when `old_r` is retrieved from `p->perfect` does kernel use
tcindex_filter_result_init() to clear the old filter result, which
triggers the above memory leak.

Considering that there already exists a tc_filter_wq workqueue
to destroy the old tcindex_data by tcindex_partial_destroy_work()
at the end of tcindex_set_parms(), this patch solves
this memory leak bug by removing this old filter result
clearing part and delegating it to the tc_filter_wq workqueue.

Note that this patch doesn't introduce any other issues. If
`old_r` is retrieved from `p->perfect`, this patch just
delegates old filter result clearing part to the
tc_filter_wq workqueue; If `old_r` is retrieved from `p->h`,
kernel doesn't reach the old filter result clearing part, so
removing this part has no effect.

[Thanks to the suggestion from Jakub Kicinski, Cong Wang, Paolo Abeni
and Dmitry Vyukov]

Fixes: b9a24bb76bf6 ("net_sched: properly handle failure case of tcf_exts_init()")
Link: https://lore.kernel.org/all/0000000000001de5c505ebc9ec59@google.com/
Reported-by: syzbot+232ebdbd36706c965ebf@syzkaller.appspotmail.com
Tested-by: syzbot+232ebdbd36706c965ebf@syzkaller.appspotmail.com
Cc: Cong Wang <cong.wang@bytedance.com>
Cc: Jakub Kicinski <kuba@kernel.org>
Cc: Paolo Abeni <pabeni@redhat.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Acked-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Hawkins Jiawei <yin31149@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-01-18 11:41:57 +01:00
Cong Wang
93e794d4fe net_sched: reject TCF_EM_SIMPLE case for complex ematch module
[ Upstream commit 9cd3fd2054c3b3055163accbf2f31a4426f10317 ]

When TCF_EM_SIMPLE was introduced, it is supposed to be convenient
for ematch implementation:

https://lore.kernel.org/all/20050105110048.GO26856@postel.suug.ch/

"You don't have to, providing a 32bit data chunk without TCF_EM_SIMPLE
set will simply result in allocating & copy. It's an optimization,
nothing more."

So if an ematch module provides ops->datalen that means it wants a
complex data structure (saved in its em->data) instead of a simple u32
value. We should simply reject such a combination, otherwise this u32
could be misinterpreted as a pointer.

Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Reported-and-tested-by: syzbot+4caeae4c7103813598ae@syzkaller.appspotmail.com
Reported-by: Jun Nie <jun.nie@linaro.org>
Cc: Jamal Hadi Salim <jhs@mojatatu.com>
Cc: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Cong Wang <cong.wang@bytedance.com>
Acked-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-01-18 11:41:33 +01:00
Dan Carpenter
52e0429471 net: sched: Fix use after free in red_enqueue()
[ Upstream commit 8bdc2acd420c6f3dd1f1c78750ec989f02a1e2b9 ]

We can't use "skb" again after passing it to qdisc_enqueue().  This is
basically identical to commit 2f09707d0c97 ("sch_sfb: Also store skb
len before calling child enqueue").

Fixes: d7f4f332f082 ("sch_red: update backlog as well")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-11-10 17:57:50 +01:00
Zhengchao Shao
bc8301ea7e net: sched: cake: fix null pointer access issue when cake_init() fails
[ Upstream commit 51f9a8921ceacd7bf0d3f47fa867a64988ba1dcb ]

When the default qdisc is cake, if the qdisc of dev_queue fails to be
inited during mqprio_init(), cake_reset() is invoked to clear
resources. In this case, the tins is NULL, and it will cause gpf issue.

The process is as follows:
qdisc_create_dflt()
	cake_init()
		q->tins = kvcalloc(...)        --->failed, q->tins is NULL
	...
	qdisc_put()
		...
		cake_reset()
			...
			cake_dequeue_one()
				b = &q->tins[...]   --->q->tins is NULL

The following is the Call Trace information:
general protection fault, probably for non-canonical address
0xdffffc0000000000: 0000 [#1] PREEMPT SMP KASAN
KASAN: null-ptr-deref in range [0x0000000000000000-0x0000000000000007]
RIP: 0010:cake_dequeue_one+0xc9/0x3c0
Call Trace:
<TASK>
cake_reset+0xb1/0x140
qdisc_reset+0xed/0x6f0
qdisc_destroy+0x82/0x4c0
qdisc_put+0x9e/0xb0
qdisc_create_dflt+0x2c3/0x4a0
mqprio_init+0xa71/0x1760
qdisc_create+0x3eb/0x1000
tc_modify_qdisc+0x408/0x1720
rtnetlink_rcv_msg+0x38e/0xac0
netlink_rcv_skb+0x12d/0x3a0
netlink_unicast+0x4a2/0x740
netlink_sendmsg+0x826/0xcc0
sock_sendmsg+0xc5/0x100
____sys_sendmsg+0x583/0x690
___sys_sendmsg+0xe8/0x160
__sys_sendmsg+0xbf/0x160
do_syscall_64+0x35/0x80
entry_SYSCALL_64_after_hwframe+0x46/0xb0
RIP: 0033:0x7f89e5122d04
</TASK>

Fixes: 046f6fd5daef ("sched: Add Common Applications Kept Enhanced (cake) qdisc")
Signed-off-by: Zhengchao Shao <shaozhengchao@huawei.com>
Acked-by: Toke Høiland-Jørgensen <toke@toke.dk>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-10-29 10:20:35 +02:00
Hangyu Hua
903f7d322c net: sched: fix possible refcount leak in tc_new_tfilter()
[ Upstream commit c2e1cfefcac35e0eea229e148c8284088ce437b5 ]

tfilter_put need to be called to put the refount got by tp->ops->get to
avoid possible refcount leak when chain->tmplt_ops != NULL and
chain->tmplt_ops != tp->ops.

Fixes: 7d5509fa0d3d ("net: sched: extend proto ops with 'put' callback")
Signed-off-by: Hangyu Hua <hbh25y@gmail.com>
Reviewed-by: Vlad Buslov <vladbu@nvidia.com>
Link: https://lore.kernel.org/r/20220921092734.31700-1-hbh25y@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-09-28 11:04:07 +02:00
Vladimir Oltean
6a3239f806 net/sched: taprio: make qdisc_leaf() see the per-netdev-queue pfifo child qdiscs
[ Upstream commit 1461d212ab277d8bba1a753d33e9afe03d81f9d4 ]

taprio can only operate as root qdisc, and to that end, there exists the
following check in taprio_init(), just as in mqprio:

	if (sch->parent != TC_H_ROOT)
		return -EOPNOTSUPP;

And indeed, when we try to attach taprio to an mqprio child, it fails as
expected:

$ tc qdisc add dev swp0 root handle 1: mqprio num_tc 8 \
	map 0 1 2 3 4 5 6 7 \
	queues 1@0 1@1 1@2 1@3 1@4 1@5 1@6 1@7 hw 0
$ tc qdisc replace dev swp0 parent 1:2 taprio num_tc 8 \
	map 0 1 2 3 4 5 6 7 \
	queues 1@0 1@1 1@2 1@3 1@4 1@5 1@6 1@7 \
	base-time 0 sched-entry S 0x7f 990000 sched-entry S 0x80 100000 \
	flags 0x0 clockid CLOCK_TAI
Error: sch_taprio: Can only be attached as root qdisc.

(extack message added by me)

But when we try to attach a taprio child to a taprio root qdisc,
surprisingly it doesn't fail:

$ tc qdisc replace dev swp0 root handle 1: taprio num_tc 8 \
	map 0 1 2 3 4 5 6 7 queues 1@0 1@1 1@2 1@3 1@4 1@5 1@6 1@7 \
	base-time 0 sched-entry S 0x7f 990000 sched-entry S 0x80 100000 \
	flags 0x0 clockid CLOCK_TAI
$ tc qdisc replace dev swp0 parent 1:2 taprio num_tc 8 \
	map 0 1 2 3 4 5 6 7 \
	queues 1@0 1@1 1@2 1@3 1@4 1@5 1@6 1@7 \
	base-time 0 sched-entry S 0x7f 990000 sched-entry S 0x80 100000 \
	flags 0x0 clockid CLOCK_TAI

This is because tc_modify_qdisc() behaves differently when mqprio is
root, vs when taprio is root.

In the mqprio case, it finds the parent qdisc through
p = qdisc_lookup(dev, TC_H_MAJ(clid)), and then the child qdisc through
q = qdisc_leaf(p, clid). This leaf qdisc q has handle 0, so it is
ignored according to the comment right below ("It may be default qdisc,
ignore it"). As a result, tc_modify_qdisc() goes through the
qdisc_create() code path, and this gives taprio_init() a chance to check
for sch_parent != TC_H_ROOT and error out.

Whereas in the taprio case, the returned q = qdisc_leaf(p, clid) is
different. It is not the default qdisc created for each netdev queue
(both taprio and mqprio call qdisc_create_dflt() and keep them in
a private q->qdiscs[], or priv->qdiscs[], respectively). Instead, taprio
makes qdisc_leaf() return the _root_ qdisc, aka itself.

When taprio does that, tc_modify_qdisc() goes through the qdisc_change()
code path, because the qdisc layer never finds out about the child qdisc
of the root. And through the ->change() ops, taprio has no reason to
check whether its parent is root or not, just through ->init(), which is
not called.

The problem is the taprio_leaf() implementation. Even though code wise,
it does the exact same thing as mqprio_leaf() which it is copied from,
it works with different input data. This is because mqprio does not
attach itself (the root) to each device TX queue, but one of the default
qdiscs from its private array.

In fact, since commit 13511704f8d7 ("net: taprio offload: enforce qdisc
to netdev queue mapping"), taprio does this too, but just for the full
offload case. So if we tried to attach a taprio child to a fully
offloaded taprio root qdisc, it would properly fail too; just not to a
software root taprio.

To fix the problem, stop looking at the Qdisc that's attached to the TX
queue, and instead, always return the default qdiscs that we've
allocated (and to which we privately enqueue and dequeue, in software
scheduling mode).

Since Qdisc_class_ops :: leaf  is only called from tc_modify_qdisc(),
the risk of unforeseen side effects introduced by this change is
minimal.

Fixes: 5a781ccbd19e ("tc: Add support for configuring the taprio scheduler")
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: Vinicius Costa Gomes <vinicius.gomes@intel.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-09-28 11:04:07 +02:00
Vladimir Oltean
d12a1eb070 net/sched: taprio: avoid disabling offload when it was never enabled
[ Upstream commit db46e3a88a09c5cf7e505664d01da7238cd56c92 ]

In an incredibly strange API design decision, qdisc->destroy() gets
called even if qdisc->init() never succeeded, not exclusively since
commit 87b60cfacf9f ("net_sched: fix error recovery at qdisc creation"),
but apparently also earlier (in the case of qdisc_create_dflt()).

The taprio qdisc does not fully acknowledge this when it attempts full
offload, because it starts off with q->flags = TAPRIO_FLAGS_INVALID in
taprio_init(), then it replaces q->flags with TCA_TAPRIO_ATTR_FLAGS
parsed from netlink (in taprio_change(), tail called from taprio_init()).

But in taprio_destroy(), we call taprio_disable_offload(), and this
determines what to do based on FULL_OFFLOAD_IS_ENABLED(q->flags).

But looking at the implementation of FULL_OFFLOAD_IS_ENABLED()
(a bitwise check of bit 1 in q->flags), it is invalid to call this macro
on q->flags when it contains TAPRIO_FLAGS_INVALID, because that is set
to U32_MAX, and therefore FULL_OFFLOAD_IS_ENABLED() will return true on
an invalid set of flags.

As a result, it is possible to crash the kernel if user space forces an
error between setting q->flags = TAPRIO_FLAGS_INVALID, and the calling
of taprio_enable_offload(). This is because drivers do not expect the
offload to be disabled when it was never enabled.

The error that we force here is to attach taprio as a non-root qdisc,
but instead as child of an mqprio root qdisc:

$ tc qdisc add dev swp0 root handle 1: \
	mqprio num_tc 8 map 0 1 2 3 4 5 6 7 \
	queues 1@0 1@1 1@2 1@3 1@4 1@5 1@6 1@7 hw 0
$ tc qdisc replace dev swp0 parent 1:1 \
	taprio num_tc 8 map 0 1 2 3 4 5 6 7 \
	queues 1@0 1@1 1@2 1@3 1@4 1@5 1@6 1@7 base-time 0 \
	sched-entry S 0x7f 990000 sched-entry S 0x80 100000 \
	flags 0x0 clockid CLOCK_TAI
Unable to handle kernel paging request at virtual address fffffffffffffff8
[fffffffffffffff8] pgd=0000000000000000, p4d=0000000000000000
Internal error: Oops: 96000004 [#1] PREEMPT SMP
Call trace:
 taprio_dump+0x27c/0x310
 vsc9959_port_setup_tc+0x1f4/0x460
 felix_port_setup_tc+0x24/0x3c
 dsa_slave_setup_tc+0x54/0x27c
 taprio_disable_offload.isra.0+0x58/0xe0
 taprio_destroy+0x80/0x104
 qdisc_create+0x240/0x470
 tc_modify_qdisc+0x1fc/0x6b0
 rtnetlink_rcv_msg+0x12c/0x390
 netlink_rcv_skb+0x5c/0x130
 rtnetlink_rcv+0x1c/0x2c

Fix this by keeping track of the operations we made, and undo the
offload only if we actually did it.

I've added "bool offloaded" inside a 4 byte hole between "int clockid"
and "atomic64_t picos_per_byte". Now the first cache line looks like
below:

$ pahole -C taprio_sched net/sched/sch_taprio.o
struct taprio_sched {
        struct Qdisc * *           qdiscs;               /*     0     8 */
        struct Qdisc *             root;                 /*     8     8 */
        u32                        flags;                /*    16     4 */
        enum tk_offsets            tk_offset;            /*    20     4 */
        int                        clockid;              /*    24     4 */
        bool                       offloaded;            /*    28     1 */

        /* XXX 3 bytes hole, try to pack */

        atomic64_t                 picos_per_byte;       /*    32     0 */

        /* XXX 8 bytes hole, try to pack */

        spinlock_t                 current_entry_lock;   /*    40     0 */

        /* XXX 8 bytes hole, try to pack */

        struct sched_entry *       current_entry;        /*    48     8 */
        struct sched_gate_list *   oper_sched;           /*    56     8 */
        /* --- cacheline 1 boundary (64 bytes) --- */

Fixes: 9c66d1564676 ("taprio: Add support for hardware offloading")
Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Reviewed-by: Vinicius Costa Gomes <vinicius.gomes@intel.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-09-28 11:04:06 +02:00
Toke Høiland-Jørgensen
64f9755b40 sch_sfb: Also store skb len before calling child enqueue
[ Upstream commit 2f09707d0c972120bf794cfe0f0c67e2c2ddb252 ]

Cong Wang noticed that the previous fix for sch_sfb accessing the queued
skb after enqueueing it to a child qdisc was incomplete: the SFB enqueue
function was also calling qdisc_qstats_backlog_inc() after enqueue, which
reads the pkt len from the skb cb field. Fix this by also storing the skb
len, and using the stored value to increment the backlog after enqueueing.

Fixes: 9efd23297cca ("sch_sfb: Don't assume the skb is still around after enqueueing to child")
Signed-off-by: Toke Høiland-Jørgensen <toke@toke.dk>
Acked-by: Cong Wang <cong.wang@bytedance.com>
Link: https://lore.kernel.org/r/20220905192137.965549-1-toke@toke.dk
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-09-15 12:04:56 +02:00
Toke Høiland-Jørgensen
279c7668e3 sch_sfb: Don't assume the skb is still around after enqueueing to child
[ Upstream commit 9efd23297cca530bb35e1848665805d3fcdd7889 ]

The sch_sfb enqueue() routine assumes the skb is still alive after it has
been enqueued into a child qdisc, using the data in the skb cb field in the
increment_qlen() routine after enqueue. However, the skb may in fact have
been freed, causing a use-after-free in this case. In particular, this
happens if sch_cake is used as a child of sfb, and the GSO splitting mode
of CAKE is enabled (in which case the skb will be split into segments and
the original skb freed).

Fix this by copying the sfb cb data to the stack before enqueueing the skb,
and using this stack copy in increment_qlen() instead of the skb pointer
itself.

Reported-by: zdi-disclosures@trendmicro.com # ZDI-CAN-18231
Fixes: e13e02a3c68d ("net_sched: SFB flow scheduler")
Signed-off-by: Toke Høiland-Jørgensen <toke@toke.dk>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-09-15 12:04:55 +02:00
Jakub Kicinski
47e6794316 Revert "sch_cake: Return __NET_XMIT_STOLEN when consuming enqueued skb"
[ Upstream commit 0b4f688d53fdc2a731b9d9cdf0c96255bc024ea6 ]

This reverts commit 90fabae8a2c225c4e4936723c38857887edde5cc.

Patch was applied hastily, revert and let the v2 be reviewed.

Fixes: 90fabae8a2c2 ("sch_cake: Return __NET_XMIT_STOLEN when consuming enqueued skb")
Link: https://lore.kernel.org/all/87wnao2ha3.fsf@toke.dk/
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-09-15 12:04:50 +02:00
Toke Høiland-Jørgensen
f8a94fdf02 sch_cake: Return __NET_XMIT_STOLEN when consuming enqueued skb
[ Upstream commit 90fabae8a2c225c4e4936723c38857887edde5cc ]

When the GSO splitting feature of sch_cake is enabled, GSO superpackets
will be broken up and the resulting segments enqueued in place of the
original skb. In this case, CAKE calls consume_skb() on the original skb,
but still returns NET_XMIT_SUCCESS. This can confuse parent qdiscs into
assuming the original skb still exists, when it really has been freed. Fix
this by adding the __NET_XMIT_STOLEN flag to the return value in this case.

Fixes: 0c850344d388 ("sch_cake: Conditionally split GSO segments")
Signed-off-by: Toke Høiland-Jørgensen <toke@toke.dk>
Reported-by: zdi-disclosures@trendmicro.com # ZDI-CAN-18231
Link: https://lore.kernel.org/r/20220831092103.442868-1-toke@toke.dk
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-09-15 12:04:50 +02:00
Zhengchao Shao
fffa19b5e5 net: sched: tbf: don't call qdisc_put() while holding tree lock
[ Upstream commit b05972f01e7d30419987a1f221b5593668fd6448 ]

The issue is the same to commit c2999f7fb05b ("net: sched: multiq: don't
call qdisc_put() while holding tree lock"). Qdiscs call qdisc_put() while
holding sch tree spinlock, which results sleeping-while-atomic BUG.

Fixes: c266f64dbfa2 ("net: sched: protect block state with mutex")
Signed-off-by: Zhengchao Shao <shaozhengchao@huawei.com>
Link: https://lore.kernel.org/r/20220826013930.340121-1-shaozhengchao@huawei.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-09-15 12:04:50 +02:00
Kuniyuki Iwashima
c1d0ef0e6f net: Fix data-races around weight_p and dev_weight_[rt]x_bias.
[ Upstream commit bf955b5ab8f6f7b0632cdef8e36b14e4f6e77829 ]

While reading weight_p, it can be changed concurrently.  Thus, we need
to add READ_ONCE() to its reader.

Also, dev_[rt]x_weight can be read/written at the same time.  So, we
need to use READ_ONCE() and WRITE_ONCE() for its access.  Moreover, to
use the same weight_p while changing dev_[rt]x_weight, we add a mutex
in proc_do_dev_weight().

Fixes: 3d48b53fb2ae ("net: dev_weight: TX/RX orthogonality")
Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-09-05 10:27:41 +02:00
Jamal Hadi Salim
992480132e net_sched: cls_route: disallow handle of 0
commit 02799571714dc5dd6948824b9d080b44a295f695 upstream.

Follows up on:
https://lore.kernel.org/all/20220809170518.164662-1-cascardo@canonical.com/

handle of 0 implies from/to of universe realm which is not very
sensible.

Lets see what this patch will do:
$sudo tc qdisc add dev $DEV root handle 1:0 prio

//lets manufacture a way to insert handle of 0
$sudo tc filter add dev $DEV parent 1:0 protocol ip prio 100 \
route to 0 from 0 classid 1:10 action ok

//gets rejected...
Error: handle of 0 is not valid.
We have an error talking to the kernel, -1

//lets create a legit entry..
sudo tc filter add dev $DEV parent 1:0 protocol ip prio 100 route from 10 \
classid 1:10 action ok

//what did the kernel insert?
$sudo tc filter ls dev $DEV parent 1:0
filter protocol ip pref 100 route chain 0
filter protocol ip pref 100 route chain 0 fh 0x000a8000 flowid 1:10 from 10
	action order 1: gact action pass
	 random type none pass val 0
	 index 1 ref 1 bind 1

//Lets try to replace that legit entry with a handle of 0
$ sudo tc filter replace dev $DEV parent 1:0 protocol ip prio 100 \
handle 0x000a8000 route to 0 from 0 classid 1:10 action drop

Error: Replacing with handle of 0 is invalid.
We have an error talking to the kernel, -1

And last, lets run Cascardo's POC:
$ ./poc
0
0
-22
-22
-22

Signed-off-by: Jamal Hadi Salim <jhs@mojatatu.com>
Acked-by: Stephen Hemminger <stephen@networkplumber.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-08-25 11:18:18 +02:00
Thadeu Lima de Souza Cascardo
1fcd691cc2 net_sched: cls_route: remove from list when handle is 0
commit 9ad36309e2719a884f946678e0296be10f0bb4c1 upstream.

When a route filter is replaced and the old filter has a 0 handle, the old
one won't be removed from the hashtable, while it will still be freed.

The test was there since before commit 1109c00547fc ("net: sched: RCU
cls_route"), when a new filter was not allocated when there was an old one.
The old filter was reused and the reinserting would only be necessary if an
old filter was replaced. That was still wrong for the same case where the
old handle was 0.

Remove the old filter from the list independently from its handle value.

This fixes CVE-2022-2588, also reported as ZDI-CAN-17440.

Reported-by: Zhenpeng Lin <zplin@u.northwestern.edu>
Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo@canonical.com>
Reviewed-by: Kamal Mostafa <kamal@canonical.com>
Cc: <stable@vger.kernel.org>
Acked-by: Jamal Hadi Salim <jhs@mojatatu.com>
Link: https://lore.kernel.org/r/20220809170518.164662-1-cascardo@canonical.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-08-25 11:18:15 +02:00
Victor Nogueira
bb1dc7cc57 net/sched: act_api: Notify user space if any actions were flushed before error
commit 76b39b94382f9e0a639e1c70c3253de248cc4c83 upstream.

If during an action flush operation one of the actions is still being
referenced, the flush operation is aborted and the kernel returns to
user space with an error. However, if the kernel was able to flush, for
example, 3 actions and failed on the fourth, the kernel will not notify
user space that it deleted 3 actions before failing.

This patch fixes that behaviour by notifying user space of how many
actions were deleted before flush failed and by setting extack with a
message describing what happened.

Fixes: 55334a5db5cd ("net_sched: act: refuse to remove bound action outside")
Signed-off-by: Victor Nogueira <victor@mojatatu.com>
Acked-by: Jamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-07-07 17:36:50 +02:00
Peilin Ye
f1f9c2a5a3 net/sched: sch_netem: Fix arithmetic in netem_dump() for 32-bit platforms
[ Upstream commit a2b1a5d40bd12b44322c2ccd40bb0ec1699708b6 ]

As reported by Yuming, currently tc always show a latency of UINT_MAX
for netem Qdisc's on 32-bit platforms:

    $ tc qdisc add dev dummy0 root netem latency 100ms
    $ tc qdisc show dev dummy0
    qdisc netem 8001: root refcnt 2 limit 1000 delay 275s  275s
                                               ^^^^^^^^^^^^^^^^

Let us take a closer look at netem_dump():

        qopt.latency = min_t(psched_tdiff_t, PSCHED_NS2TICKS(q->latency,
                             UINT_MAX);

qopt.latency is __u32, psched_tdiff_t is signed long,
(psched_tdiff_t)(UINT_MAX) is negative for 32-bit platforms, so
qopt.latency is always UINT_MAX.

Fix it by using psched_time_t (u64) instead.

Note: confusingly, users have two ways to specify 'latency':

  1. normally, via '__u32 latency' in struct tc_netem_qopt;
  2. via the TCA_NETEM_LATENCY64 attribute, which is s64.

For the second case, theoretically 'latency' could be negative.  This
patch ignores that corner case, since it is broken (i.e. assigning a
negative s64 to __u32) anyways, and should be handled separately.

Thanks Ted Lin for the analysis [1] .

[1] https://github.com/raspberrypi/linux/issues/3512

Reported-by: Yuming Chen <chenyuming.junnan@bytedance.com>
Fixes: 112f9cb65643 ("netem: convert to qdisc_watchdog_schedule_ns")
Reviewed-by: Cong Wang <cong.wang@bytedance.com>
Signed-off-by: Peilin Ye <peilin.ye@bytedance.com>
Acked-by: Stephen Hemminger <stephen@networkplumber.org>
Link: https://lore.kernel.org/r/20220616234336.2443-1-yepeilin.cs@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-06-29 08:58:46 +02:00
Davide Caratti
b47319b4aa net/sched: act_police: more accurate MTU policing
commit 4ddc844eb81da59bfb816d8d52089aba4e59e269 upstream.

in current Linux, MTU policing does not take into account that packets at
the TC ingress have the L2 header pulled. Thus, the same TC police action
(with the same value of tcfp_mtu) behaves differently for ingress/egress.
In addition, the full GSO size is compared to tcfp_mtu: as a consequence,
the policer drops GSO packets even when individual segments have the L2 +
L3 + L4 + payload length below the configured valued of tcfp_mtu.

Improve the accuracy of MTU policing as follows:
 - account for mac_len for non-GSO packets at TC ingress.
 - compare MTU threshold with the segmented size for GSO packets.
Also, add a kselftest that verifies the correct behavior.

Signed-off-by: Davide Caratti <dcaratti@redhat.com>
Reviewed-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
[dcaratti: fix conflicts due to lack of the following commits:
 - commit 2ffe0395288a ("net/sched: act_police: add support for
   packet-per-second policing")
 - commit afe231d32eb5 ("selftests: forwarding: Add tc-police tests")
 - commit 53b61f29367d ("selftests: forwarding: Add tc-police tests for
   packets per second")]
Link: https://lore.kernel.org/netdev/876d597a0ff55f6ba786f73c5a9fd9eb8d597a03.1644514748.git.dcaratti@redhat.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-06-22 14:11:24 +02:00
Paolo Abeni
1eb2d78581 net/sched: act_pedit: sanitize shift argument before usage
[ Upstream commit 4d42d54a7d6aa6d29221d3fd4f2ae9503e94f011 ]

syzbot was able to trigger an Out-of-Bound on the pedit action:

UBSAN: shift-out-of-bounds in net/sched/act_pedit.c:238:43
shift exponent 1400735974 is too large for 32-bit type 'unsigned int'
CPU: 0 PID: 3606 Comm: syz-executor151 Not tainted 5.18.0-rc5-syzkaller-00165-g810c2f0a3f86 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106
 ubsan_epilogue+0xb/0x50 lib/ubsan.c:151
 __ubsan_handle_shift_out_of_bounds.cold+0xb1/0x187 lib/ubsan.c:322
 tcf_pedit_init.cold+0x1a/0x1f net/sched/act_pedit.c:238
 tcf_action_init_1+0x414/0x690 net/sched/act_api.c:1367
 tcf_action_init+0x530/0x8d0 net/sched/act_api.c:1432
 tcf_action_add+0xf9/0x480 net/sched/act_api.c:1956
 tc_ctl_action+0x346/0x470 net/sched/act_api.c:2015
 rtnetlink_rcv_msg+0x413/0xb80 net/core/rtnetlink.c:5993
 netlink_rcv_skb+0x153/0x420 net/netlink/af_netlink.c:2502
 netlink_unicast_kernel net/netlink/af_netlink.c:1319 [inline]
 netlink_unicast+0x543/0x7f0 net/netlink/af_netlink.c:1345
 netlink_sendmsg+0x904/0xe00 net/netlink/af_netlink.c:1921
 sock_sendmsg_nosec net/socket.c:705 [inline]
 sock_sendmsg+0xcf/0x120 net/socket.c:725
 ____sys_sendmsg+0x6e2/0x800 net/socket.c:2413
 ___sys_sendmsg+0xf3/0x170 net/socket.c:2467
 __sys_sendmsg+0xe5/0x1b0 net/socket.c:2496
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae
RIP: 0033:0x7fe36e9e1b59
Code: 28 c3 e8 2a 14 00 00 66 2e 0f 1f 84 00 00 00 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 c0 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ffef796fe88 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007fe36e9e1b59
RDX: 0000000000000000 RSI: 0000000020000300 RDI: 0000000000000003
RBP: 00007fe36e9a5d00 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 00007fe36e9a5d90
R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000
 </TASK>

The 'shift' field is not validated, and any value above 31 will
trigger out-of-bounds. The issue predates the git history, but
syzbot was able to trigger it only after the commit mentioned in
the fixes tag, and this change only applies on top of such commit.

Address the issue bounding the 'shift' value to the maximum allowed
by the relevant operator.

Reported-and-tested-by: syzbot+8ed8fc4c57e9dcf23ca6@syzkaller.appspotmail.com
Fixes: 8b796475fd78 ("net/sched: act_pedit: really ensure the skb is writable")
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-05-25 09:14:35 +02:00
Paolo Abeni
2ec2dd7d51 net/sched: act_pedit: really ensure the skb is writable
[ Upstream commit 8b796475fd7882663a870456466a4fb315cc1bd6 ]

Currently pedit tries to ensure that the accessed skb offset
is writable via skb_unclone(). The action potentially allows
touching any skb bytes, so it may end-up modifying shared data.

The above causes some sporadic MPTCP self-test failures, due to
this code:

	tc -n $ns2 filter add dev ns2eth$i egress \
		protocol ip prio 1000 \
		handle 42 fw \
		action pedit munge offset 148 u8 invert \
		pipe csum tcp \
		index 100

The above modifies a data byte outside the skb head and the skb is
a cloned one, carrying a TCP output packet.

This change addresses the issue by keeping track of a rough
over-estimate highest skb offset accessed by the action and ensuring
such offset is really writable.

Note that this may cause performance regressions in some scenarios,
but hopefully pedit is not in the critical path.

Fixes: db2c24175d14 ("act_pedit: access skb->data safely")
Acked-by: Mat Martineau <mathew.j.martineau@linux.intel.com>
Tested-by: Geliang Tang <geliang.tang@suse.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Acked-by: Jamal Hadi Salim <jhs@mojatatu.com>
Link: https://lore.kernel.org/r/1fcf78e6679d0a287dd61bb0f04730ce33b3255d.1652194627.git.pabeni@redhat.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-05-18 09:47:25 +02:00
Eric Dumazet
8c5ca6492a net/sched: cls_u32: fix possible leak in u32_init_knode()
[ Upstream commit ec5b0f605b105457f257f2870acad4a5d463984b ]

While investigating a related syzbot report,
I found that whenever call to tcf_exts_init()
from u32_init_knode() is failing, we end up
with an elevated refcount on ht->refcnt

To avoid that, only increase the refcount after
all possible errors have been evaluated.

Fixes: b9a24bb76bf6 ("net_sched: properly handle failure case of tcf_exts_init()")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Cong Wang <xiyou.wangcong@gmail.com>
Cc: Jiri Pirko <jiri@resnulli.us>
Acked-by: Jamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-04-27 13:50:47 +02:00
Eric Dumazet
5a4f3eba21 net/sched: cls_u32: fix netns refcount changes in u32_change()
commit 3db09e762dc79584a69c10d74a6b98f89a9979f8 upstream.

We are now able to detect extra put_net() at the moment
they happen, instead of much later in correct code paths.

u32_init_knode() / tcf_exts_init() populates the ->exts.net
pointer, but as mentioned in tcf_exts_init(),
the refcount on netns has not been elevated yet.

The refcount is taken only once tcf_exts_get_net()
is called.

So the two u32_destroy_key() calls from u32_change()
are attempting to release an invalid reference on the netns.

syzbot report:

refcount_t: decrement hit 0; leaking memory.
WARNING: CPU: 0 PID: 21708 at lib/refcount.c:31 refcount_warn_saturate+0xbf/0x1e0 lib/refcount.c:31
Modules linked in:
CPU: 0 PID: 21708 Comm: syz-executor.5 Not tainted 5.18.0-rc2-next-20220412-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:refcount_warn_saturate+0xbf/0x1e0 lib/refcount.c:31
Code: 1d 14 b6 b2 09 31 ff 89 de e8 6d e9 89 fd 84 db 75 e0 e8 84 e5 89 fd 48 c7 c7 40 aa 26 8a c6 05 f4 b5 b2 09 01 e8 e5 81 2e 05 <0f> 0b eb c4 e8 68 e5 89 fd 0f b6 1d e3 b5 b2 09 31 ff 89 de e8 38
RSP: 0018:ffffc900051af1b0 EFLAGS: 00010286
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000
RDX: 0000000000040000 RSI: ffffffff8160a0c8 RDI: fffff52000a35e28
RBP: 0000000000000004 R08: 0000000000000000 R09: 0000000000000000
R10: ffffffff81604a9e R11: 0000000000000000 R12: 1ffff92000a35e3b
R13: 00000000ffffffef R14: ffff8880211a0194 R15: ffff8880577d0a00
FS:  00007f25d183e700(0000) GS:ffff8880b9c00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f19c859c028 CR3: 0000000051009000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 __refcount_dec include/linux/refcount.h:344 [inline]
 refcount_dec include/linux/refcount.h:359 [inline]
 ref_tracker_free+0x535/0x6b0 lib/ref_tracker.c:118
 netns_tracker_free include/net/net_namespace.h:327 [inline]
 put_net_track include/net/net_namespace.h:341 [inline]
 tcf_exts_put_net include/net/pkt_cls.h:255 [inline]
 u32_destroy_key.isra.0+0xa7/0x2b0 net/sched/cls_u32.c:394
 u32_change+0xe01/0x3140 net/sched/cls_u32.c:909
 tc_new_tfilter+0x98d/0x2200 net/sched/cls_api.c:2148
 rtnetlink_rcv_msg+0x80d/0xb80 net/core/rtnetlink.c:6016
 netlink_rcv_skb+0x153/0x420 net/netlink/af_netlink.c:2495
 netlink_unicast_kernel net/netlink/af_netlink.c:1319 [inline]
 netlink_unicast+0x543/0x7f0 net/netlink/af_netlink.c:1345
 netlink_sendmsg+0x904/0xe00 net/netlink/af_netlink.c:1921
 sock_sendmsg_nosec net/socket.c:705 [inline]
 sock_sendmsg+0xcf/0x120 net/socket.c:725
 ____sys_sendmsg+0x6e2/0x800 net/socket.c:2413
 ___sys_sendmsg+0xf3/0x170 net/socket.c:2467
 __sys_sendmsg+0xe5/0x1b0 net/socket.c:2496
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae
RIP: 0033:0x7f25d0689049
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f25d183e168 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007f25d079c030 RCX: 00007f25d0689049
RDX: 0000000000000000 RSI: 0000000020000340 RDI: 0000000000000005
RBP: 00007f25d06e308d R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007ffd0b752e3f R14: 00007f25d183e300 R15: 0000000000022000
 </TASK>

Fixes: 35c55fc156d8 ("cls_u32: use tcf_exts_get_net() before call_rcu()")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: syzbot <syzkaller@googlegroups.com>
Cc: Cong Wang <xiyou.wangcong@gmail.com>
Cc: Jiri Pirko <jiri@resnulli.us>
Acked-by: Jamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-04-27 13:50:46 +02:00
Benedikt Spranger
99a435c378 net/sched: taprio: Check if socket flags are valid
[ Upstream commit e8a64bbaaad1f6548cec5508297bc6d45e8ab69e ]

A user may set the SO_TXTIME socket option to ensure a packet is send
at a given time. The taprio scheduler has to confirm, that it is allowed
to send a packet at that given time, by a check against the packet time
schedule. The scheduler drop the packet, if the gates are closed at the
given send time.

The check, if SO_TXTIME is set, may fail since sk_flags are part of an
union and the union is used otherwise. This happen, if a socket is not
a full socket, like a request socket for example.

Add a check to verify, if the union is used for sk_flags.

Fixes: 4cfd5779bd6e ("taprio: Add support for txtime-assist mode")
Signed-off-by: Benedikt Spranger <b.spranger@linutronix.de>
Reviewed-by: Kurt Kanzenbach <kurt@linutronix.de>
Acked-by: Vinicius Costa Gomes <vinicius.gomes@intel.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-04-20 09:19:35 +02:00
Marcelo Ricardo Leitner
94541468c1 net/sched: fix initialization order when updating chain 0 head
[ Upstream commit e65812fd22eba32f11abe28cb377cbd64cfb1ba0 ]

Currently, when inserting a new filter that needs to sit at the head
of chain 0, it will first update the heads pointer on all devices using
the (shared) block, and only then complete the initialization of the new
element so that it has a "next" element.

This can lead to a situation that the chain 0 head is propagated to
another CPU before the "next" initialization is done. When this race
condition is triggered, packets being matched on that CPU will simply
miss all other filters, and will flow through the stack as if there were
no other filters installed. If the system is using OVS + TC, such
packets will get handled by vswitchd via upcall, which results in much
higher latency and reordering. For other applications it may result in
packet drops.

This is reproducible with a tc only setup, but it varies from system to
system. It could be reproduced with a shared block amongst 10 veth
tunnels, and an ingress filter mirroring packets to another veth.
That's because using the last added veth tunnel to the shared block to
do the actual traffic, it makes the race window bigger and easier to
trigger.

The fix is rather simple, to just initialize the next pointer of the new
filter instance (tp) before propagating the head change.

The fixes tag is pointing to the original code though this issue should
only be observed when using it unlocked.

Fixes: 2190d1d0944f ("net: sched: introduce helpers to work with filter chains")
Signed-off-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Signed-off-by: Vlad Buslov <vladbu@nvidia.com>
Reviewed-by: Davide Caratti <dcaratti@redhat.com>
Link: https://lore.kernel.org/r/b97d5f4eaffeeb9d058155bcab63347527261abf.1649341369.git.marcelo.leitner@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-04-20 09:19:35 +02:00
Vlad Buslov
5f2e543918 net/sched: flower: fix parsing of ethertype following VLAN header
[ Upstream commit 2105f700b53c24aa48b65c15652acc386044d26a ]

A tc flower filter matching TCA_FLOWER_KEY_VLAN_ETH_TYPE is expected to
match the L2 ethertype following the first VLAN header, as confirmed by
linked discussion with the maintainer. However, such rule also matches
packets that have additional second VLAN header, even though filter has
both eth_type and vlan_ethtype set to "ipv4". Looking at the code this
seems to be mostly an artifact of the way flower uses flow dissector.
First, even though looking at the uAPI eth_type and vlan_ethtype appear
like a distinct fields, in flower they are all mapped to the same
key->basic.n_proto. Second, flow dissector skips following VLAN header as
no keys for FLOW_DISSECTOR_KEY_CVLAN are set and eventually assigns the
value of n_proto to last parsed header. With these, such filters ignore any
headers present between first VLAN header and first "non magic"
header (ipv4 in this case) that doesn't result
FLOW_DISSECT_RET_PROTO_AGAIN.

Fix the issue by extending flow dissector VLAN key structure with new
'vlan_eth_type' field that matches first ethertype following previously
parsed VLAN header. Modify flower classifier to set the new
flow_dissector_key_vlan->vlan_eth_type with value obtained from
TCA_FLOWER_KEY_VLAN_ETH_TYPE/TCA_FLOWER_KEY_CVLAN_ETH_TYPE uAPIs.

Link: https://lore.kernel.org/all/Yjhgi48BpTGh6dig@nanopsycho/
Fixes: 9399ae9a6cb2 ("net_sched: flower: Add vlan support")
Fixes: d64efd0926ba ("net/sched: flower: Add supprt for matching on QinQ vlan headers")
Signed-off-by: Vlad Buslov <vladbu@nvidia.com>
Reviewed-by: Jiri Pirko <jiri@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-04-20 09:19:34 +02:00
Eric Dumazet
c83049cb88 net: sched: limit TC_ACT_REPEAT loops
commit 5740d068909676d4bdb5c9c00c37a83df7728909 upstream.

We have been living dangerously, at the mercy of malicious users,
abusing TC_ACT_REPEAT, as shown by this syzpot report [1].

Add an arbitrary limit (32) to the number of times an action can
return TC_ACT_REPEAT.

v2: switch the limit to 32 instead of 10.
    Use net_warn_ratelimited() instead of pr_err_once().

[1] (C repro available on demand)

rcu: INFO: rcu_preempt self-detected stall on CPU
rcu:    1-...!: (10500 ticks this GP) idle=021/1/0x4000000000000000 softirq=5592/5592 fqs=0
        (t=10502 jiffies g=5305 q=190)
rcu: rcu_preempt kthread timer wakeup didn't happen for 10502 jiffies! g5305 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402
rcu:    Possible timer handling issue on cpu=0 timer-softirq=3527
rcu: rcu_preempt kthread starved for 10505 jiffies! g5305 f0x0 RCU_GP_WAIT_FQS(5) ->state=0x402 ->cpu=0
rcu:    Unless rcu_preempt kthread gets sufficient CPU time, OOM is now expected behavior.
rcu: RCU grace-period kthread stack dump:
task:rcu_preempt     state:I stack:29344 pid:   14 ppid:     2 flags:0x00004000
Call Trace:
 <TASK>
 context_switch kernel/sched/core.c:4986 [inline]
 __schedule+0xab2/0x4db0 kernel/sched/core.c:6295
 schedule+0xd2/0x260 kernel/sched/core.c:6368
 schedule_timeout+0x14a/0x2a0 kernel/time/timer.c:1881
 rcu_gp_fqs_loop+0x186/0x810 kernel/rcu/tree.c:1963
 rcu_gp_kthread+0x1de/0x320 kernel/rcu/tree.c:2136
 kthread+0x2e9/0x3a0 kernel/kthread.c:377
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
 </TASK>
rcu: Stack dump where RCU GP kthread last ran:
Sending NMI from CPU 1 to CPUs 0:
NMI backtrace for cpu 0
CPU: 0 PID: 3646 Comm: syz-executor358 Not tainted 5.17.0-rc3-syzkaller-00149-gbf8e59fd315f #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:rep_nop arch/x86/include/asm/vdso/processor.h:13 [inline]
RIP: 0010:cpu_relax arch/x86/include/asm/vdso/processor.h:18 [inline]
RIP: 0010:pv_wait_head_or_lock kernel/locking/qspinlock_paravirt.h:437 [inline]
RIP: 0010:__pv_queued_spin_lock_slowpath+0x3b8/0xb40 kernel/locking/qspinlock.c:508
Code: 48 89 eb c6 45 01 01 41 bc 00 80 00 00 48 c1 e9 03 83 e3 07 41 be 01 00 00 00 48 b8 00 00 00 00 00 fc ff df 4c 8d 2c 01 eb 0c <f3> 90 41 83 ec 01 0f 84 72 04 00 00 41 0f b6 45 00 38 d8 7f 08 84
RSP: 0018:ffffc9000283f1b0 EFLAGS: 00000206
RAX: 0000000000000003 RBX: 0000000000000000 RCX: 1ffff1100fc0071e
RDX: 0000000000000001 RSI: 0000000000000201 RDI: 0000000000000000
RBP: ffff88807e0038f0 R08: 0000000000000001 R09: ffffffff8ffbf9ff
R10: 0000000000000001 R11: 0000000000000001 R12: 0000000000004c1e
R13: ffffed100fc0071e R14: 0000000000000001 R15: ffff8880b9c3aa80
FS:  00005555562bf300(0000) GS:ffff8880b9c00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007ffdbfef12b8 CR3: 00000000723c2000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 pv_queued_spin_lock_slowpath arch/x86/include/asm/paravirt.h:591 [inline]
 queued_spin_lock_slowpath arch/x86/include/asm/qspinlock.h:51 [inline]
 queued_spin_lock include/asm-generic/qspinlock.h:85 [inline]
 do_raw_spin_lock+0x200/0x2b0 kernel/locking/spinlock_debug.c:115
 spin_lock_bh include/linux/spinlock.h:354 [inline]
 sch_tree_lock include/net/sch_generic.h:610 [inline]
 sch_tree_lock include/net/sch_generic.h:605 [inline]
 prio_tune+0x3b9/0xb50 net/sched/sch_prio.c:211
 prio_init+0x5c/0x80 net/sched/sch_prio.c:244
 qdisc_create.constprop.0+0x44a/0x10f0 net/sched/sch_api.c:1253
 tc_modify_qdisc+0x4c5/0x1980 net/sched/sch_api.c:1660
 rtnetlink_rcv_msg+0x413/0xb80 net/core/rtnetlink.c:5594
 netlink_rcv_skb+0x153/0x420 net/netlink/af_netlink.c:2494
 netlink_unicast_kernel net/netlink/af_netlink.c:1317 [inline]
 netlink_unicast+0x539/0x7e0 net/netlink/af_netlink.c:1343
 netlink_sendmsg+0x904/0xe00 net/netlink/af_netlink.c:1919
 sock_sendmsg_nosec net/socket.c:705 [inline]
 sock_sendmsg+0xcf/0x120 net/socket.c:725
 ____sys_sendmsg+0x6e8/0x810 net/socket.c:2413
 ___sys_sendmsg+0xf3/0x170 net/socket.c:2467
 __sys_sendmsg+0xe5/0x1b0 net/socket.c:2496
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae
RIP: 0033:0x7f7ee98aae99
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 41 15 00 00 90 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 c0 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007ffdbfef12d8 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 00007ffdbfef1300 RCX: 00007f7ee98aae99
RDX: 0000000000000000 RSI: 0000000020000000 RDI: 0000000000000003
RBP: 0000000000000000 R08: 000000000000000d R09: 000000000000000d
R10: 000000000000000d R11: 0000000000000246 R12: 00007ffdbfef12f0
R13: 00000000000f4240 R14: 000000000004ca47 R15: 00007ffdbfef12e4
 </TASK>
INFO: NMI handler (nmi_cpu_backtrace_handler) took too long to run: 2.293 msecs
NMI backtrace for cpu 1
CPU: 1 PID: 3260 Comm: kworker/1:3 Not tainted 5.17.0-rc3-syzkaller-00149-gbf8e59fd315f #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: mld mld_ifc_work
Call Trace:
 <IRQ>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106
 nmi_cpu_backtrace.cold+0x47/0x144 lib/nmi_backtrace.c:111
 nmi_trigger_cpumask_backtrace+0x1b3/0x230 lib/nmi_backtrace.c:62
 trigger_single_cpu_backtrace include/linux/nmi.h:164 [inline]
 rcu_dump_cpu_stacks+0x25e/0x3f0 kernel/rcu/tree_stall.h:343
 print_cpu_stall kernel/rcu/tree_stall.h:604 [inline]
 check_cpu_stall kernel/rcu/tree_stall.h:688 [inline]
 rcu_pending kernel/rcu/tree.c:3919 [inline]
 rcu_sched_clock_irq.cold+0x5c/0x759 kernel/rcu/tree.c:2617
 update_process_times+0x16d/0x200 kernel/time/timer.c:1785
 tick_sched_handle+0x9b/0x180 kernel/time/tick-sched.c:226
 tick_sched_timer+0x1b0/0x2d0 kernel/time/tick-sched.c:1428
 __run_hrtimer kernel/time/hrtimer.c:1685 [inline]
 __hrtimer_run_queues+0x1c0/0xe50 kernel/time/hrtimer.c:1749
 hrtimer_interrupt+0x31c/0x790 kernel/time/hrtimer.c:1811
 local_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1086 [inline]
 __sysvec_apic_timer_interrupt+0x146/0x530 arch/x86/kernel/apic/apic.c:1103
 sysvec_apic_timer_interrupt+0x8e/0xc0 arch/x86/kernel/apic/apic.c:1097
 </IRQ>
 <TASK>
 asm_sysvec_apic_timer_interrupt+0x12/0x20 arch/x86/include/asm/idtentry.h:638
RIP: 0010:__sanitizer_cov_trace_const_cmp4+0xc/0x70 kernel/kcov.c:286
Code: 00 00 00 48 89 7c 30 e8 48 89 4c 30 f0 4c 89 54 d8 20 48 89 10 5b c3 0f 1f 80 00 00 00 00 41 89 f8 bf 03 00 00 00 4c 8b 14 24 <89> f1 65 48 8b 34 25 00 70 02 00 e8 14 f9 ff ff 84 c0 74 4b 48 8b
RSP: 0018:ffffc90002c5eea8 EFLAGS: 00000246
RAX: 0000000000000007 RBX: ffff88801c625800 RCX: 0000000000000000
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000003
RBP: ffff8880137d3100 R08: 0000000000000000 R09: 0000000000000000
R10: ffffffff874fcd88 R11: 0000000000000000 R12: ffff88801d692dc0
R13: ffff8880137d3104 R14: 0000000000000000 R15: ffff88801d692de8
 tcf_police_act+0x358/0x11d0 net/sched/act_police.c:256
 tcf_action_exec net/sched/act_api.c:1049 [inline]
 tcf_action_exec+0x1a6/0x530 net/sched/act_api.c:1026
 tcf_exts_exec include/net/pkt_cls.h:326 [inline]
 route4_classify+0xef0/0x1400 net/sched/cls_route.c:179
 __tcf_classify net/sched/cls_api.c:1549 [inline]
 tcf_classify+0x3e8/0x9d0 net/sched/cls_api.c:1615
 prio_classify net/sched/sch_prio.c:42 [inline]
 prio_enqueue+0x3a7/0x790 net/sched/sch_prio.c:75
 dev_qdisc_enqueue+0x40/0x300 net/core/dev.c:3668
 __dev_xmit_skb net/core/dev.c:3756 [inline]
 __dev_queue_xmit+0x1f61/0x3660 net/core/dev.c:4081
 neigh_hh_output include/net/neighbour.h:533 [inline]
 neigh_output include/net/neighbour.h:547 [inline]
 ip_finish_output2+0x14dc/0x2170 net/ipv4/ip_output.c:228
 __ip_finish_output net/ipv4/ip_output.c:306 [inline]
 __ip_finish_output+0x396/0x650 net/ipv4/ip_output.c:288
 ip_finish_output+0x32/0x200 net/ipv4/ip_output.c:316
 NF_HOOK_COND include/linux/netfilter.h:296 [inline]
 ip_output+0x196/0x310 net/ipv4/ip_output.c:430
 dst_output include/net/dst.h:451 [inline]
 ip_local_out+0xaf/0x1a0 net/ipv4/ip_output.c:126
 iptunnel_xmit+0x628/0xa50 net/ipv4/ip_tunnel_core.c:82
 geneve_xmit_skb drivers/net/geneve.c:966 [inline]
 geneve_xmit+0x10c8/0x3530 drivers/net/geneve.c:1077
 __netdev_start_xmit include/linux/netdevice.h:4683 [inline]
 netdev_start_xmit include/linux/netdevice.h:4697 [inline]
 xmit_one net/core/dev.c:3473 [inline]
 dev_hard_start_xmit+0x1eb/0x920 net/core/dev.c:3489
 __dev_queue_xmit+0x2985/0x3660 net/core/dev.c:4116
 neigh_hh_output include/net/neighbour.h:533 [inline]
 neigh_output include/net/neighbour.h:547 [inline]
 ip6_finish_output2+0xf7a/0x14f0 net/ipv6/ip6_output.c:126
 __ip6_finish_output net/ipv6/ip6_output.c:191 [inline]
 __ip6_finish_output+0x61e/0xe90 net/ipv6/ip6_output.c:170
 ip6_finish_output+0x32/0x200 net/ipv6/ip6_output.c:201
 NF_HOOK_COND include/linux/netfilter.h:296 [inline]
 ip6_output+0x1e4/0x530 net/ipv6/ip6_output.c:224
 dst_output include/net/dst.h:451 [inline]
 NF_HOOK include/linux/netfilter.h:307 [inline]
 NF_HOOK include/linux/netfilter.h:301 [inline]
 mld_sendpack+0x9a3/0xe40 net/ipv6/mcast.c:1826
 mld_send_cr net/ipv6/mcast.c:2127 [inline]
 mld_ifc_work+0x71c/0xdc0 net/ipv6/mcast.c:2659
 process_one_work+0x9ac/0x1650 kernel/workqueue.c:2307
 worker_thread+0x657/0x1110 kernel/workqueue.c:2454
 kthread+0x2e9/0x3a0 kernel/kthread.c:377
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
 </TASK>
----------------
Code disassembly (best guess):
   0:   48 89 eb                mov    %rbp,%rbx
   3:   c6 45 01 01             movb   $0x1,0x1(%rbp)
   7:   41 bc 00 80 00 00       mov    $0x8000,%r12d
   d:   48 c1 e9 03             shr    $0x3,%rcx
  11:   83 e3 07                and    $0x7,%ebx
  14:   41 be 01 00 00 00       mov    $0x1,%r14d
  1a:   48 b8 00 00 00 00 00    movabs $0xdffffc0000000000,%rax
  21:   fc ff df
  24:   4c 8d 2c 01             lea    (%rcx,%rax,1),%r13
  28:   eb 0c                   jmp    0x36
* 2a:   f3 90                   pause <-- trapping instruction
  2c:   41 83 ec 01             sub    $0x1,%r12d
  30:   0f 84 72 04 00 00       je     0x4a8
  36:   41 0f b6 45 00          movzbl 0x0(%r13),%eax
  3b:   38 d8                   cmp    %bl,%al
  3d:   7f 08                   jg     0x47
  3f:   84                      .byte 0x84

Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Acked-by: Jamal Hadi Salim <jhs@mojatatu.com>
Cc: Cong Wang <xiyou.wangcong@gmail.com>
Cc: Jiri Pirko <jiri@resnulli.us>
Reported-by: syzbot <syzkaller@googlegroups.com>
Link: https://lore.kernel.org/r/20220215235305.3272331-1-eric.dumazet@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-02-23 11:59:59 +01:00
Victor Nogueira
9babdef288 net: sched: Clarify error message when qdisc kind is unknown
[ Upstream commit 973bf8fdd12f0e70ea351c018e68edd377a836d1 ]

When adding a tc rule with a qdisc kind that is not supported or not
compiled into the kernel, the kernel emits the following error: "Error:
Specified qdisc not found.". Found via tdc testing when ETS qdisc was not
compiled in and it was not obvious right away what the message meant
without looking at the kernel code.

Change the error message to be more explicit and say the qdisc kind is
unknown.

Signed-off-by: Victor Nogueira <victor@mojatatu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-02-16 12:52:48 +01:00
Eric Dumazet
b1d17e920d net: sched: fix use-after-free in tc_new_tfilter()
commit 04c2a47ffb13c29778e2a14e414ad4cb5a5db4b5 upstream.

Whenever tc_new_tfilter() jumps back to replay: label,
we need to make sure @q and @chain local variables are cleared again,
or risk use-after-free as in [1]

For consistency, apply the same fix in tc_ctl_chain()

BUG: KASAN: use-after-free in mini_qdisc_pair_swap+0x1b9/0x1f0 net/sched/sch_generic.c:1581
Write of size 8 at addr ffff8880985c4b08 by task syz-executor.4/1945

CPU: 0 PID: 1945 Comm: syz-executor.4 Not tainted 5.17.0-rc1-syzkaller-00495-gff58831fa02d #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106
 print_address_description.constprop.0.cold+0x8d/0x336 mm/kasan/report.c:255
 __kasan_report mm/kasan/report.c:442 [inline]
 kasan_report.cold+0x83/0xdf mm/kasan/report.c:459
 mini_qdisc_pair_swap+0x1b9/0x1f0 net/sched/sch_generic.c:1581
 tcf_chain_head_change_item net/sched/cls_api.c:372 [inline]
 tcf_chain0_head_change.isra.0+0xb9/0x120 net/sched/cls_api.c:386
 tcf_chain_tp_insert net/sched/cls_api.c:1657 [inline]
 tcf_chain_tp_insert_unique net/sched/cls_api.c:1707 [inline]
 tc_new_tfilter+0x1e67/0x2350 net/sched/cls_api.c:2086
 rtnetlink_rcv_msg+0x80d/0xb80 net/core/rtnetlink.c:5583
 netlink_rcv_skb+0x153/0x420 net/netlink/af_netlink.c:2494
 netlink_unicast_kernel net/netlink/af_netlink.c:1317 [inline]
 netlink_unicast+0x539/0x7e0 net/netlink/af_netlink.c:1343
 netlink_sendmsg+0x904/0xe00 net/netlink/af_netlink.c:1919
 sock_sendmsg_nosec net/socket.c:705 [inline]
 sock_sendmsg+0xcf/0x120 net/socket.c:725
 ____sys_sendmsg+0x331/0x810 net/socket.c:2413
 ___sys_sendmsg+0xf3/0x170 net/socket.c:2467
 __sys_sendmmsg+0x195/0x470 net/socket.c:2553
 __do_sys_sendmmsg net/socket.c:2582 [inline]
 __se_sys_sendmmsg net/socket.c:2579 [inline]
 __x64_sys_sendmmsg+0x99/0x100 net/socket.c:2579
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae
RIP: 0033:0x7f2647172059
Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007f2645aa5168 EFLAGS: 00000246 ORIG_RAX: 0000000000000133
RAX: ffffffffffffffda RBX: 00007f2647285100 RCX: 00007f2647172059
RDX: 040000000000009f RSI: 00000000200002c0 RDI: 0000000000000006
RBP: 00007f26471cc08d R08: 0000000000000000 R09: 0000000000000000
R10: 9e00000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007fffb3f7f02f R14: 00007f2645aa5300 R15: 0000000000022000
 </TASK>

Allocated by task 1944:
 kasan_save_stack+0x1e/0x40 mm/kasan/common.c:38
 kasan_set_track mm/kasan/common.c:45 [inline]
 set_alloc_info mm/kasan/common.c:436 [inline]
 ____kasan_kmalloc mm/kasan/common.c:515 [inline]
 ____kasan_kmalloc mm/kasan/common.c:474 [inline]
 __kasan_kmalloc+0xa9/0xd0 mm/kasan/common.c:524
 kmalloc_node include/linux/slab.h:604 [inline]
 kzalloc_node include/linux/slab.h:726 [inline]
 qdisc_alloc+0xac/0xa10 net/sched/sch_generic.c:941
 qdisc_create.constprop.0+0xce/0x10f0 net/sched/sch_api.c:1211
 tc_modify_qdisc+0x4c5/0x1980 net/sched/sch_api.c:1660
 rtnetlink_rcv_msg+0x413/0xb80 net/core/rtnetlink.c:5592
 netlink_rcv_skb+0x153/0x420 net/netlink/af_netlink.c:2494
 netlink_unicast_kernel net/netlink/af_netlink.c:1317 [inline]
 netlink_unicast+0x539/0x7e0 net/netlink/af_netlink.c:1343
 netlink_sendmsg+0x904/0xe00 net/netlink/af_netlink.c:1919
 sock_sendmsg_nosec net/socket.c:705 [inline]
 sock_sendmsg+0xcf/0x120 net/socket.c:725
 ____sys_sendmsg+0x331/0x810 net/socket.c:2413
 ___sys_sendmsg+0xf3/0x170 net/socket.c:2467
 __sys_sendmmsg+0x195/0x470 net/socket.c:2553
 __do_sys_sendmmsg net/socket.c:2582 [inline]
 __se_sys_sendmmsg net/socket.c:2579 [inline]
 __x64_sys_sendmmsg+0x99/0x100 net/socket.c:2579
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae

Freed by task 3609:
 kasan_save_stack+0x1e/0x40 mm/kasan/common.c:38
 kasan_set_track+0x21/0x30 mm/kasan/common.c:45
 kasan_set_free_info+0x20/0x30 mm/kasan/generic.c:370
 ____kasan_slab_free mm/kasan/common.c:366 [inline]
 ____kasan_slab_free+0x130/0x160 mm/kasan/common.c:328
 kasan_slab_free include/linux/kasan.h:236 [inline]
 slab_free_hook mm/slub.c:1728 [inline]
 slab_free_freelist_hook+0x8b/0x1c0 mm/slub.c:1754
 slab_free mm/slub.c:3509 [inline]
 kfree+0xcb/0x280 mm/slub.c:4562
 rcu_do_batch kernel/rcu/tree.c:2527 [inline]
 rcu_core+0x7b8/0x1540 kernel/rcu/tree.c:2778
 __do_softirq+0x29b/0x9c2 kernel/softirq.c:558

Last potentially related work creation:
 kasan_save_stack+0x1e/0x40 mm/kasan/common.c:38
 __kasan_record_aux_stack+0xbe/0xd0 mm/kasan/generic.c:348
 __call_rcu kernel/rcu/tree.c:3026 [inline]
 call_rcu+0xb1/0x740 kernel/rcu/tree.c:3106
 qdisc_put_unlocked+0x6f/0x90 net/sched/sch_generic.c:1109
 tcf_block_release+0x86/0x90 net/sched/cls_api.c:1238
 tc_new_tfilter+0xc0d/0x2350 net/sched/cls_api.c:2148
 rtnetlink_rcv_msg+0x80d/0xb80 net/core/rtnetlink.c:5583
 netlink_rcv_skb+0x153/0x420 net/netlink/af_netlink.c:2494
 netlink_unicast_kernel net/netlink/af_netlink.c:1317 [inline]
 netlink_unicast+0x539/0x7e0 net/netlink/af_netlink.c:1343
 netlink_sendmsg+0x904/0xe00 net/netlink/af_netlink.c:1919
 sock_sendmsg_nosec net/socket.c:705 [inline]
 sock_sendmsg+0xcf/0x120 net/socket.c:725
 ____sys_sendmsg+0x331/0x810 net/socket.c:2413
 ___sys_sendmsg+0xf3/0x170 net/socket.c:2467
 __sys_sendmmsg+0x195/0x470 net/socket.c:2553
 __do_sys_sendmmsg net/socket.c:2582 [inline]
 __se_sys_sendmmsg net/socket.c:2579 [inline]
 __x64_sys_sendmmsg+0x99/0x100 net/socket.c:2579
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae

The buggy address belongs to the object at ffff8880985c4800
 which belongs to the cache kmalloc-1k of size 1024
The buggy address is located 776 bytes inside of
 1024-byte region [ffff8880985c4800, ffff8880985c4c00)
The buggy address belongs to the page:
page:ffffea0002617000 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x985c0
head:ffffea0002617000 order:3 compound_mapcount:0 compound_pincount:0
flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff)
raw: 00fff00000010200 0000000000000000 dead000000000122 ffff888010c41dc0
raw: 0000000000000000 0000000000100010 00000001ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 3, migratetype Unmovable, gfp_mask 0x1d20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC|__GFP_HARDWALL), pid 1941, ts 1038999441284, free_ts 1033444432829
 prep_new_page mm/page_alloc.c:2434 [inline]
 get_page_from_freelist+0xa72/0x2f50 mm/page_alloc.c:4165
 __alloc_pages+0x1b2/0x500 mm/page_alloc.c:5389
 alloc_pages+0x1aa/0x310 mm/mempolicy.c:2271
 alloc_slab_page mm/slub.c:1799 [inline]
 allocate_slab mm/slub.c:1944 [inline]
 new_slab+0x28a/0x3b0 mm/slub.c:2004
 ___slab_alloc+0x87c/0xe90 mm/slub.c:3018
 __slab_alloc.constprop.0+0x4d/0xa0 mm/slub.c:3105
 slab_alloc_node mm/slub.c:3196 [inline]
 slab_alloc mm/slub.c:3238 [inline]
 __kmalloc+0x2fb/0x340 mm/slub.c:4420
 kmalloc include/linux/slab.h:586 [inline]
 kzalloc include/linux/slab.h:715 [inline]
 __register_sysctl_table+0x112/0x1090 fs/proc/proc_sysctl.c:1335
 neigh_sysctl_register+0x2c8/0x5e0 net/core/neighbour.c:3787
 devinet_sysctl_register+0xb1/0x230 net/ipv4/devinet.c:2618
 inetdev_init+0x286/0x580 net/ipv4/devinet.c:278
 inetdev_event+0xa8a/0x15d0 net/ipv4/devinet.c:1532
 notifier_call_chain+0xb5/0x200 kernel/notifier.c:84
 call_netdevice_notifiers_info+0xb5/0x130 net/core/dev.c:1919
 call_netdevice_notifiers_extack net/core/dev.c:1931 [inline]
 call_netdevice_notifiers net/core/dev.c:1945 [inline]
 register_netdevice+0x1073/0x1500 net/core/dev.c:9698
 veth_newlink+0x59c/0xa90 drivers/net/veth.c:1722
page last free stack trace:
 reset_page_owner include/linux/page_owner.h:24 [inline]
 free_pages_prepare mm/page_alloc.c:1352 [inline]
 free_pcp_prepare+0x374/0x870 mm/page_alloc.c:1404
 free_unref_page_prepare mm/page_alloc.c:3325 [inline]
 free_unref_page+0x19/0x690 mm/page_alloc.c:3404
 release_pages+0x748/0x1220 mm/swap.c:956
 tlb_batch_pages_flush mm/mmu_gather.c:50 [inline]
 tlb_flush_mmu_free mm/mmu_gather.c:243 [inline]
 tlb_flush_mmu+0xe9/0x6b0 mm/mmu_gather.c:250
 zap_pte_range mm/memory.c:1441 [inline]
 zap_pmd_range mm/memory.c:1490 [inline]
 zap_pud_range mm/memory.c:1519 [inline]
 zap_p4d_range mm/memory.c:1540 [inline]
 unmap_page_range+0x1d1d/0x2a30 mm/memory.c:1561
 unmap_single_vma+0x198/0x310 mm/memory.c:1606
 unmap_vmas+0x16b/0x2f0 mm/memory.c:1638
 exit_mmap+0x201/0x670 mm/mmap.c:3178
 __mmput+0x122/0x4b0 kernel/fork.c:1114
 mmput+0x56/0x60 kernel/fork.c:1135
 exit_mm kernel/exit.c:507 [inline]
 do_exit+0xa3c/0x2a30 kernel/exit.c:793
 do_group_exit+0xd2/0x2f0 kernel/exit.c:935
 __do_sys_exit_group kernel/exit.c:946 [inline]
 __se_sys_exit_group kernel/exit.c:944 [inline]
 __x64_sys_exit_group+0x3a/0x50 kernel/exit.c:944
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae

Memory state around the buggy address:
 ffff8880985c4a00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff8880985c4a80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff8880985c4b00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                      ^
 ffff8880985c4b80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff8880985c4c00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc

Fixes: 470502de5bdb ("net: sched: unlock rules update API")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Vlad Buslov <vladbu@mellanox.com>
Cc: Jiri Pirko <jiri@mellanox.com>
Cc: Cong Wang <xiyou.wangcong@gmail.com>
Reported-by: syzbot <syzkaller@googlegroups.com>
Link: https://lore.kernel.org/r/20220131172018.3704490-1-eric.dumazet@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-02-05 12:35:37 +01:00
Kevin Bracey
3bd7629eb8 net_sched: restore "mpu xxx" handling
commit fb80445c438c78b40b547d12b8d56596ce4ccfeb upstream.

commit 56b765b79e9a ("htb: improved accuracy at high rates") broke
"overhead X", "linklayer atm" and "mpu X" attributes.

"overhead X" and "linklayer atm" have already been fixed. This restores
the "mpu X" handling, as might be used by DOCSIS or Ethernet shaping:

    tc class add ... htb rate X overhead 4 mpu 64

The code being fixed is used by htb, tbf and act_police. Cake has its
own mpu handling. qdisc_calculate_pkt_len still uses the size table
containing values adjusted for mpu by user space.

iproute2 tc has always passed mpu into the kernel via a tc_ratespec
structure, but the kernel never directly acted on it, merely stored it
so that it could be read back by `tc class show`.

Rather, tc would generate length-to-time tables that included the mpu
(and linklayer) in their construction, and the kernel used those tables.

Since v3.7, the tables were no longer used. Along with "mpu", this also
broke "overhead" and "linklayer" which were fixed in 01cb71d2d47b
("net_sched: restore "overhead xxx" handling", v3.10) and 8a8e3d84b171
("net_sched: restore "linklayer atm" handling", v3.11).

"overhead" was fixed by simply restoring use of tc_ratespec::overhead -
this had originally been used by the kernel but was initially omitted
from the new non-table-based calculations.

"linklayer" had been handled in the table like "mpu", but the mode was
not originally passed in tc_ratespec. The new implementation was made to
handle it by getting new versions of tc to pass the mode in an extended
tc_ratespec, and for older versions of tc the table contents were analysed
at load time to deduce linklayer.

As "mpu" has always been given to the kernel in tc_ratespec,
accompanying the mpu-based table, we can restore system functionality
with no userspace change by making the kernel act on the tc_ratespec
value.

Fixes: 56b765b79e9a ("htb: improved accuracy at high rates")
Signed-off-by: Kevin Bracey <kevin@bracey.fi>
Cc: Eric Dumazet <edumazet@google.com>
Cc: Jiri Pirko <jiri@resnulli.us>
Cc: Vimalkumar <j.vimal@gmail.com>
Link: https://lore.kernel.org/r/20220112170210.1014351-1-kevin@bracey.fi
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-01-27 09:19:55 +01:00
Eric Dumazet
c0db2e1e60 sch_qfq: prevent shift-out-of-bounds in qfq_init_qdisc
commit 7d18a07897d07495ee140dd319b0e9265c0f68ba upstream.

tx_queue_len can be set to ~0U, we need to be more
careful about overflows.

__fls(0) is undefined, as this report shows:

UBSAN: shift-out-of-bounds in net/sched/sch_qfq.c:1430:24
shift exponent 51770272 is too large for 32-bit type 'int'
CPU: 0 PID: 25574 Comm: syz-executor.0 Not tainted 5.16.0-rc7-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0x201/0x2d8 lib/dump_stack.c:106
 ubsan_epilogue lib/ubsan.c:151 [inline]
 __ubsan_handle_shift_out_of_bounds+0x494/0x530 lib/ubsan.c:330
 qfq_init_qdisc+0x43f/0x450 net/sched/sch_qfq.c:1430
 qdisc_create+0x895/0x1430 net/sched/sch_api.c:1253
 tc_modify_qdisc+0x9d9/0x1e20 net/sched/sch_api.c:1660
 rtnetlink_rcv_msg+0x934/0xe60 net/core/rtnetlink.c:5571
 netlink_rcv_skb+0x200/0x470 net/netlink/af_netlink.c:2496
 netlink_unicast_kernel net/netlink/af_netlink.c:1319 [inline]
 netlink_unicast+0x814/0x9f0 net/netlink/af_netlink.c:1345
 netlink_sendmsg+0xaea/0xe60 net/netlink/af_netlink.c:1921
 sock_sendmsg_nosec net/socket.c:704 [inline]
 sock_sendmsg net/socket.c:724 [inline]
 ____sys_sendmsg+0x5b9/0x910 net/socket.c:2409
 ___sys_sendmsg net/socket.c:2463 [inline]
 __sys_sendmsg+0x280/0x370 net/socket.c:2492
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x44/0xd0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae

Fixes: 462dbc9101ac ("pkt_sched: QFQ Plus: fair-queueing service at DRR cost")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: syzbot <syzkaller@googlegroups.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-01-11 15:23:32 +01:00
Baowen Zheng
9cb405ee53 flow_offload: return EOPNOTSUPP for the unsupported mpls action type
[ Upstream commit 166b6a46b78bf8b9559a6620c3032f9fe492e082 ]

We need to return EOPNOTSUPP for the unsupported mpls action type when
setup the flow action.

In the original implement, we will return 0 for the unsupported mpls
action type, actually we do not setup it and the following actions
to the flow action entry.

Fixes: 9838b20a7fb2 ("net: sched: take rtnl lock in tc_setup_flow_action()")
Signed-off-by: Baowen Zheng <baowen.zheng@corigine.com>
Signed-off-by: Simon Horman <simon.horman@corigine.com>
Acked-by: Jamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-12-22 09:29:37 +01:00
Vlad Buslov
066a637d1c net: sched: lock action when translating it to flow_action infra
[ Upstream commit 7a47281439ba00b11fc098f36695522184ce5a82 ]

In order to remove dependency on rtnl lock, take action's tcfa_lock when
constructing its representation as flow_action_entry structure.

Refactor tcf_sample_get_group() to assume that caller holds tcf_lock and
don't take it manually. This callback is only called from flow_action infra
representation translator which now calls it with tcf_lock held, so this
refactoring is necessary to prevent deadlock.

Allocate memory with GFP_ATOMIC flag for ip_tunnel_info copy because
tcf_tunnel_info_copy() is only called from flow_action representation infra
code with tcf_lock spinlock taken.

Signed-off-by: Vlad Buslov <vladbu@mellanox.com>
Acked-by: Jiri Pirko <jiri@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-12-22 09:29:37 +01:00
Eric Dumazet
0d80462fbd sch_cake: do not call cake_destroy() from cake_init()
[ Upstream commit ab443c53916730862cec202078d36fd4008bea79 ]

qdiscs are not supposed to call their own destroy() method
from init(), because core stack already does that.

syzbot was able to trigger use after free:

DEBUG_LOCKS_WARN_ON(lock->magic != lock)
WARNING: CPU: 0 PID: 21902 at kernel/locking/mutex.c:586 __mutex_lock_common kernel/locking/mutex.c:586 [inline]
WARNING: CPU: 0 PID: 21902 at kernel/locking/mutex.c:586 __mutex_lock+0x9ec/0x12f0 kernel/locking/mutex.c:740
Modules linked in:
CPU: 0 PID: 21902 Comm: syz-executor189 Not tainted 5.16.0-rc4-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
RIP: 0010:__mutex_lock_common kernel/locking/mutex.c:586 [inline]
RIP: 0010:__mutex_lock+0x9ec/0x12f0 kernel/locking/mutex.c:740
Code: 08 84 d2 0f 85 19 08 00 00 8b 05 97 38 4b 04 85 c0 0f 85 27 f7 ff ff 48 c7 c6 20 00 ac 89 48 c7 c7 a0 fe ab 89 e8 bf 76 ba ff <0f> 0b e9 0d f7 ff ff 48 8b 44 24 40 48 8d b8 c8 08 00 00 48 89 f8
RSP: 0018:ffffc9000627f290 EFLAGS: 00010282
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 0000000000000000
RDX: ffff88802315d700 RSI: ffffffff815f1db8 RDI: fffff52000c4fe44
RBP: ffff88818f28e000 R08: 0000000000000000 R09: 0000000000000000
R10: ffffffff815ebb5e R11: 0000000000000000 R12: 0000000000000000
R13: dffffc0000000000 R14: ffffc9000627f458 R15: 0000000093c30000
FS:  0000555556abc400(0000) GS:ffff8880b9c00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007fda689c3303 CR3: 000000001cfbb000 CR4: 0000000000350ef0
Call Trace:
 <TASK>
 tcf_chain0_head_change_cb_del+0x2e/0x3d0 net/sched/cls_api.c:810
 tcf_block_put_ext net/sched/cls_api.c:1381 [inline]
 tcf_block_put_ext net/sched/cls_api.c:1376 [inline]
 tcf_block_put+0xbc/0x130 net/sched/cls_api.c:1394
 cake_destroy+0x3f/0x80 net/sched/sch_cake.c:2695
 qdisc_create.constprop.0+0x9da/0x10f0 net/sched/sch_api.c:1293
 tc_modify_qdisc+0x4c5/0x1980 net/sched/sch_api.c:1660
 rtnetlink_rcv_msg+0x413/0xb80 net/core/rtnetlink.c:5571
 netlink_rcv_skb+0x153/0x420 net/netlink/af_netlink.c:2496
 netlink_unicast_kernel net/netlink/af_netlink.c:1319 [inline]
 netlink_unicast+0x533/0x7d0 net/netlink/af_netlink.c:1345
 netlink_sendmsg+0x904/0xdf0 net/netlink/af_netlink.c:1921
 sock_sendmsg_nosec net/socket.c:704 [inline]
 sock_sendmsg+0xcf/0x120 net/socket.c:724
 ____sys_sendmsg+0x6e8/0x810 net/socket.c:2409
 ___sys_sendmsg+0xf3/0x170 net/socket.c:2463
 __sys_sendmsg+0xe5/0x1b0 net/socket.c:2492
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae
RIP: 0033:0x7f1bb06badb9
Code: Unable to access opcode bytes at RIP 0x7f1bb06bad8f.
RSP: 002b:00007fff3012a658 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 0000000000000003 RCX: 00007f1bb06badb9
RDX: 0000000000000000 RSI: 00000000200007c0 RDI: 0000000000000003
RBP: 0000000000000000 R08: 0000000000000003 R09: 0000000000000003
R10: 0000000000000003 R11: 0000000000000246 R12: 00007fff3012a688
R13: 00007fff3012a6a0 R14: 00007fff3012a6e0 R15: 00000000000013c2
 </TASK>

Fixes: 046f6fd5daef ("sched: Add Common Applications Kept Enhanced (cake) qdisc")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: syzbot <syzkaller@googlegroups.com>
Acked-by: Toke Høiland-Jørgensen <toke@toke.dk>
Link: https://lore.kernel.org/r/20211210142046.698336-1-eric.dumazet@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-12-22 09:29:36 +01:00
Xin Long
8b2c66b0f2 net: sched: act_mirred: drop dst for the direction from egress to ingress
[ Upstream commit f799ada6bf2397c351220088b9b0980125c77280 ]

Without dropping dst, the packets sent from local mirred/redirected
to ingress will may still use the old dst. ip_rcv() will drop it as
the old dst is for output and its .input is dst_discard.

This patch is to fix by also dropping dst for those packets that are
mirred or redirected from egress to ingress in act_mirred.

Note that we don't drop it for the direction change from ingress to
egress, as on which there might be a user case attaching a metadata
dst by act_tunnel_key that would be used later.

Fixes: b57dc7c13ea9 ("net/sched: Introduce action ct")
Signed-off-by: Xin Long <lucien.xin@gmail.com>
Acked-by: Cong Wang <cong.wang@bytedance.com>
Reviewed-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-11-26 10:47:19 +01:00
Eric Dumazet
07b218db54 net/sched: sch_taprio: fix undefined behavior in ktime_mono_to_any
[ Upstream commit 6dc25401cba4d428328eade8ceae717633fdd702 ]

1) if q->tk_offset == TK_OFFS_MAX, then get_tcp_tstamp() calls
   ktime_mono_to_any() with out-of-bound value.

2) if q->tk_offset is changed in taprio_parse_clockid(),
   taprio_get_time() might also call ktime_mono_to_any()
   with out-of-bound value as sysbot found:

UBSAN: array-index-out-of-bounds in kernel/time/timekeeping.c:908:27
index 3 is out of range for type 'ktime_t *[3]'
CPU: 1 PID: 25668 Comm: kworker/u4:0 Not tainted 5.15.0-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Workqueue: bat_events batadv_iv_send_outstanding_bat_ogm_packet
Call Trace:
 <TASK>
 __dump_stack lib/dump_stack.c:88 [inline]
 dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106
 ubsan_epilogue+0xb/0x5a lib/ubsan.c:151
 __ubsan_handle_out_of_bounds.cold+0x62/0x6c lib/ubsan.c:291
 ktime_mono_to_any+0x1d4/0x1e0 kernel/time/timekeeping.c:908
 get_tcp_tstamp net/sched/sch_taprio.c:322 [inline]
 get_packet_txtime net/sched/sch_taprio.c:353 [inline]
 taprio_enqueue_one+0x5b0/0x1460 net/sched/sch_taprio.c:420
 taprio_enqueue+0x3b1/0x730 net/sched/sch_taprio.c:485
 dev_qdisc_enqueue+0x40/0x300 net/core/dev.c:3785
 __dev_xmit_skb net/core/dev.c:3869 [inline]
 __dev_queue_xmit+0x1f6e/0x3630 net/core/dev.c:4194
 batadv_send_skb_packet+0x4a9/0x5f0 net/batman-adv/send.c:108
 batadv_iv_ogm_send_to_if net/batman-adv/bat_iv_ogm.c:393 [inline]
 batadv_iv_ogm_emit net/batman-adv/bat_iv_ogm.c:421 [inline]
 batadv_iv_send_outstanding_bat_ogm_packet+0x6d7/0x8e0 net/batman-adv/bat_iv_ogm.c:1701
 process_one_work+0x9b2/0x1690 kernel/workqueue.c:2298
 worker_thread+0x658/0x11f0 kernel/workqueue.c:2445
 kthread+0x405/0x4f0 kernel/kthread.c:327
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295

Fixes: 7ede7b03484b ("taprio: make clock reference conversions easier")
Fixes: 54002066100b ("taprio: Adjust timestamps for TCP packets")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Vedang Patel <vedang.patel@intel.com>
Reported-by: syzbot <syzkaller@googlegroups.com>
Reviewed-by: Vinicius Costa Gomes <vinicius.gomes@intel.com>
Link: https://lore.kernel.org/r/20211108180815.1822479-1-eric.dumazet@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-11-17 09:48:48 +01:00
Jakub Kicinski
31df731c87 net: sched: update default qdisc visibility after Tx queue cnt changes
[ Upstream commit 1e080f17750d1083e8a32f7b350584ae1cd7ff20 ]

mq / mqprio make the default child qdiscs visible. They only do
so for the qdiscs which are within real_num_tx_queues when the
device is registered. Depending on order of calls in the driver,
or if user space changes config via ethtool -L the number of
qdiscs visible under tc qdisc show will differ from the number
of queues. This is confusing to users and potentially to system
configuration scripts which try to make sure qdiscs have the
right parameters.

Add a new Qdisc_ops callback and make relevant qdiscs TTRT.

Note that this uncovers the "shortcut" created by
commit 1f27cde313d7 ("net: sched: use pfifo_fast for non real queues")
The default child qdiscs beyond initial real_num_tx are always
pfifo_fast, no matter what the sysfs setting is. Fixing this
gets a little tricky because we'd need to keep a reference
on whatever the default qdisc was at the time of creation.
In practice this is likely an non-issue the qdiscs likely have
to be configured to non-default settings, so whatever user space
is doing such configuration can replace the pfifos... now that
it will see them.

Reported-by: Matthew Massey <matthewmassey@fb.com>
Reviewed-by: Dave Taht <dave.taht@gmail.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2021-11-17 09:48:28 +01:00
Sebastian Andrzej Siewior
62d96bb68b mqprio: Correct stats in mqprio_dump_class_stats().
commit 14132690860e4d06aa3e1c4d7d8e9866ba7756dd upstream.

Introduction of lockless subqueues broke the class statistics.
Before the change stats were accumulated in `bstats' and `qstats'
on the stack which was then copied to struct gnet_dump.

After the change the `bstats' and `qstats' are initialized to 0
and never updated, yet still fed to gnet_dump. The code updates
the global qdisc->cpu_bstats and qdisc->cpu_qstats instead,
clobbering them. Most likely a copy-paste error from the code in
mqprio_dump().

__gnet_stats_copy_basic() and __gnet_stats_copy_queue() accumulate
the values for per-CPU case but for global stats they overwrite
the value, so only stats from the last loop iteration / tc end up
in sch->[bq]stats.

Use the on-stack [bq]stats variables again and add the stats manually
in the global case.

Fixes: ce679e8df7ed2 ("net: sched: add support for TCQ_F_NOLOCK subqueues to sch_mqprio")
Cc: John Fastabend <john.fastabend@gmail.com>
Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
https://lore.kernel.org/all/20211007175000.2334713-2-bigeasy@linutronix.de/
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2021-10-20 11:40:17 +02:00