Eric Dumazet
68c34ce11e
inet: fully convert sk->sk_rx_dst to RCU rules ...
commit 8f905c0e7354ef261360fb7535ea079b1082c105 upstream.
syzbot reported various issues around early demux,
one being included in this changelog [1]
sk->sk_rx_dst is using RCU protection without clearly
documenting it.
And following sequences in tcp_v4_do_rcv()/tcp_v6_do_rcv()
are not following standard RCU rules.
[a] dst_release(dst);
[b] sk->sk_rx_dst = NULL;
They look wrong because a delete operation of RCU protected
pointer is supposed to clear the pointer before
the call_rcu()/synchronize_rcu() guarding actual memory freeing.
In some cases indeed, dst could be freed before [b] is done.
We could cheat by clearing sk_rx_dst before calling
dst_release(), but this seems the right time to stick
to standard RCU annotations and debugging facilities.
[1]
BUG: KASAN: use-after-free in dst_check include/net/dst.h:470 [inline]
BUG: KASAN: use-after-free in tcp_v4_early_demux+0x95b/0x960 net/ipv4/tcp_ipv4.c:1792
Read of size 2 at addr ffff88807f1cb73a by task syz-executor.5/9204
CPU: 0 PID: 9204 Comm: syz-executor.5 Not tainted 5.16.0-rc5-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+0xcd/0x134 lib/dump_stack.c:106
print_address_description.constprop.0.cold+0x8d/0x320 mm/kasan/report.c:247
__kasan_report mm/kasan/report.c:433 [inline]
kasan_report.cold+0x83/0xdf mm/kasan/report.c:450
dst_check include/net/dst.h:470 [inline]
tcp_v4_early_demux+0x95b/0x960 net/ipv4/tcp_ipv4.c:1792
ip_rcv_finish_core.constprop.0+0x15de/0x1e80 net/ipv4/ip_input.c:340
ip_list_rcv_finish.constprop.0+0x1b2/0x6e0 net/ipv4/ip_input.c:583
ip_sublist_rcv net/ipv4/ip_input.c:609 [inline]
ip_list_rcv+0x34e/0x490 net/ipv4/ip_input.c:644
__netif_receive_skb_list_ptype net/core/dev.c:5508 [inline]
__netif_receive_skb_list_core+0x549/0x8e0 net/core/dev.c:5556
__netif_receive_skb_list net/core/dev.c:5608 [inline]
netif_receive_skb_list_internal+0x75e/0xd80 net/core/dev.c:5699
gro_normal_list net/core/dev.c:5853 [inline]
gro_normal_list net/core/dev.c:5849 [inline]
napi_complete_done+0x1f1/0x880 net/core/dev.c:6590
virtqueue_napi_complete drivers/net/virtio_net.c:339 [inline]
virtnet_poll+0xca2/0x11b0 drivers/net/virtio_net.c:1557
__napi_poll+0xaf/0x440 net/core/dev.c:7023
napi_poll net/core/dev.c:7090 [inline]
net_rx_action+0x801/0xb40 net/core/dev.c:7177
__do_softirq+0x29b/0x9c2 kernel/softirq.c:558
invoke_softirq kernel/softirq.c:432 [inline]
__irq_exit_rcu+0x123/0x180 kernel/softirq.c:637
irq_exit_rcu+0x5/0x20 kernel/softirq.c:649
common_interrupt+0x52/0xc0 arch/x86/kernel/irq.c:240
asm_common_interrupt+0x1e/0x40 arch/x86/include/asm/idtentry.h:629
RIP: 0033:0x7f5e972bfd57
Code: 39 d1 73 14 0f 1f 80 00 00 00 00 48 8b 50 f8 48 83 e8 08 48 39 ca 77 f3 48 39 c3 73 3e 48 89 13 48 8b 50 f8 48 89 38 49 8b 0e <48> 8b 3e 48 83 c3 08 48 83 c6 08 eb bc 48 39 d1 72 9e 48 39 d0 73
RSP: 002b:00007fff8a413210 EFLAGS: 00000283
RAX: 00007f5e97108990 RBX: 00007f5e97108338 RCX: ffffffff81d3aa45
RDX: ffffffff81d3aa45 RSI: 00007f5e97108340 RDI: ffffffff81d3aa45
RBP: 00007f5e97107eb8 R08: 00007f5e97108d88 R09: 0000000093c2e8d9
R10: 0000000000000000 R11: 0000000000000000 R12: 00007f5e97107eb0
R13: 00007f5e97108338 R14: 00007f5e97107ea8 R15: 0000000000000019
</TASK>
Allocated by task 13:
kasan_save_stack+0x1e/0x50 mm/kasan/common.c:38
kasan_set_track mm/kasan/common.c:46 [inline]
set_alloc_info mm/kasan/common.c:434 [inline]
__kasan_slab_alloc+0x90/0xc0 mm/kasan/common.c:467
kasan_slab_alloc include/linux/kasan.h:259 [inline]
slab_post_alloc_hook mm/slab.h:519 [inline]
slab_alloc_node mm/slub.c:3234 [inline]
slab_alloc mm/slub.c:3242 [inline]
kmem_cache_alloc+0x202/0x3a0 mm/slub.c:3247
dst_alloc+0x146/0x1f0 net/core/dst.c:92
rt_dst_alloc+0x73/0x430 net/ipv4/route.c:1613
ip_route_input_slow+0x1817/0x3a20 net/ipv4/route.c:2340
ip_route_input_rcu net/ipv4/route.c:2470 [inline]
ip_route_input_noref+0x116/0x2a0 net/ipv4/route.c:2415
ip_rcv_finish_core.constprop.0+0x288/0x1e80 net/ipv4/ip_input.c:354
ip_list_rcv_finish.constprop.0+0x1b2/0x6e0 net/ipv4/ip_input.c:583
ip_sublist_rcv net/ipv4/ip_input.c:609 [inline]
ip_list_rcv+0x34e/0x490 net/ipv4/ip_input.c:644
__netif_receive_skb_list_ptype net/core/dev.c:5508 [inline]
__netif_receive_skb_list_core+0x549/0x8e0 net/core/dev.c:5556
__netif_receive_skb_list net/core/dev.c:5608 [inline]
netif_receive_skb_list_internal+0x75e/0xd80 net/core/dev.c:5699
gro_normal_list net/core/dev.c:5853 [inline]
gro_normal_list net/core/dev.c:5849 [inline]
napi_complete_done+0x1f1/0x880 net/core/dev.c:6590
virtqueue_napi_complete drivers/net/virtio_net.c:339 [inline]
virtnet_poll+0xca2/0x11b0 drivers/net/virtio_net.c:1557
__napi_poll+0xaf/0x440 net/core/dev.c:7023
napi_poll net/core/dev.c:7090 [inline]
net_rx_action+0x801/0xb40 net/core/dev.c:7177
__do_softirq+0x29b/0x9c2 kernel/softirq.c:558
Freed by task 13:
kasan_save_stack+0x1e/0x50 mm/kasan/common.c:38
kasan_set_track+0x21/0x30 mm/kasan/common.c:46
kasan_set_free_info+0x20/0x30 mm/kasan/generic.c:370
____kasan_slab_free mm/kasan/common.c:366 [inline]
____kasan_slab_free mm/kasan/common.c:328 [inline]
__kasan_slab_free+0xff/0x130 mm/kasan/common.c:374
kasan_slab_free include/linux/kasan.h:235 [inline]
slab_free_hook mm/slub.c:1723 [inline]
slab_free_freelist_hook+0x8b/0x1c0 mm/slub.c:1749
slab_free mm/slub.c:3513 [inline]
kmem_cache_free+0xbd/0x5d0 mm/slub.c:3530
dst_destroy+0x2d6/0x3f0 net/core/dst.c:127
rcu_do_batch kernel/rcu/tree.c:2506 [inline]
rcu_core+0x7ab/0x1470 kernel/rcu/tree.c:2741
__do_softirq+0x29b/0x9c2 kernel/softirq.c:558
Last potentially related work creation:
kasan_save_stack+0x1e/0x50 mm/kasan/common.c:38
__kasan_record_aux_stack+0xf5/0x120 mm/kasan/generic.c:348
__call_rcu kernel/rcu/tree.c:2985 [inline]
call_rcu+0xb1/0x740 kernel/rcu/tree.c:3065
dst_release net/core/dst.c:177 [inline]
dst_release+0x79/0xe0 net/core/dst.c:167
tcp_v4_do_rcv+0x612/0x8d0 net/ipv4/tcp_ipv4.c:1712
sk_backlog_rcv include/net/sock.h:1030 [inline]
__release_sock+0x134/0x3b0 net/core/sock.c:2768
release_sock+0x54/0x1b0 net/core/sock.c:3300
tcp_sendmsg+0x36/0x40 net/ipv4/tcp.c:1441
inet_sendmsg+0x99/0xe0 net/ipv4/af_inet.c:819
sock_sendmsg_nosec net/socket.c:704 [inline]
sock_sendmsg+0xcf/0x120 net/socket.c:724
sock_write_iter+0x289/0x3c0 net/socket.c:1057
call_write_iter include/linux/fs.h:2162 [inline]
new_sync_write+0x429/0x660 fs/read_write.c:503
vfs_write+0x7cd/0xae0 fs/read_write.c:590
ksys_write+0x1ee/0x250 fs/read_write.c:643
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 ffff88807f1cb700
which belongs to the cache ip_dst_cache of size 176
The buggy address is located 58 bytes inside of
176-byte region [ffff88807f1cb700, ffff88807f1cb7b0)
The buggy address belongs to the page:
page:ffffea0001fc72c0 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x7f1cb
flags: 0xfff00000000200(slab|node=0|zone=1|lastcpupid=0x7ff)
raw: 00fff00000000200 dead000000000100 dead000000000122 ffff8881413bb780
raw: 0000000000000000 0000000000100010 00000001ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 0, migratetype Unmovable, gfp_mask 0x112a20(GFP_ATOMIC|__GFP_NOWARN|__GFP_NORETRY|__GFP_HARDWALL), pid 5, ts 108466983062, free_ts 108048976062
prep_new_page mm/page_alloc.c:2418 [inline]
get_page_from_freelist+0xa72/0x2f50 mm/page_alloc.c:4149
__alloc_pages+0x1b2/0x500 mm/page_alloc.c:5369
alloc_pages+0x1a7/0x300 mm/mempolicy.c:2191
alloc_slab_page mm/slub.c:1793 [inline]
allocate_slab mm/slub.c:1930 [inline]
new_slab+0x32d/0x4a0 mm/slub.c:1993
___slab_alloc+0x918/0xfe0 mm/slub.c:3022
__slab_alloc.constprop.0+0x4d/0xa0 mm/slub.c:3109
slab_alloc_node mm/slub.c:3200 [inline]
slab_alloc mm/slub.c:3242 [inline]
kmem_cache_alloc+0x35c/0x3a0 mm/slub.c:3247
dst_alloc+0x146/0x1f0 net/core/dst.c:92
rt_dst_alloc+0x73/0x430 net/ipv4/route.c:1613
__mkroute_output net/ipv4/route.c:2564 [inline]
ip_route_output_key_hash_rcu+0x921/0x2d00 net/ipv4/route.c:2791
ip_route_output_key_hash+0x18b/0x300 net/ipv4/route.c:2619
__ip_route_output_key include/net/route.h:126 [inline]
ip_route_output_flow+0x23/0x150 net/ipv4/route.c:2850
ip_route_output_key include/net/route.h:142 [inline]
geneve_get_v4_rt+0x3a6/0x830 drivers/net/geneve.c:809
geneve_xmit_skb drivers/net/geneve.c:899 [inline]
geneve_xmit+0xc4a/0x3540 drivers/net/geneve.c:1082
__netdev_start_xmit include/linux/netdevice.h:4994 [inline]
netdev_start_xmit include/linux/netdevice.h:5008 [inline]
xmit_one net/core/dev.c:3590 [inline]
dev_hard_start_xmit+0x1eb/0x920 net/core/dev.c:3606
__dev_queue_xmit+0x299a/0x3650 net/core/dev.c:4229
page last free stack trace:
reset_page_owner include/linux/page_owner.h:24 [inline]
free_pages_prepare mm/page_alloc.c:1338 [inline]
free_pcp_prepare+0x374/0x870 mm/page_alloc.c:1389
free_unref_page_prepare mm/page_alloc.c:3309 [inline]
free_unref_page+0x19/0x690 mm/page_alloc.c:3388
qlink_free mm/kasan/quarantine.c:146 [inline]
qlist_free_all+0x5a/0xc0 mm/kasan/quarantine.c:165
kasan_quarantine_reduce+0x180/0x200 mm/kasan/quarantine.c:272
__kasan_slab_alloc+0xa2/0xc0 mm/kasan/common.c:444
kasan_slab_alloc include/linux/kasan.h:259 [inline]
slab_post_alloc_hook mm/slab.h:519 [inline]
slab_alloc_node mm/slub.c:3234 [inline]
kmem_cache_alloc_node+0x255/0x3f0 mm/slub.c:3270
__alloc_skb+0x215/0x340 net/core/skbuff.c:414
alloc_skb include/linux/skbuff.h:1126 [inline]
alloc_skb_with_frags+0x93/0x620 net/core/skbuff.c:6078
sock_alloc_send_pskb+0x783/0x910 net/core/sock.c:2575
mld_newpack+0x1df/0x770 net/ipv6/mcast.c:1754
add_grhead+0x265/0x330 net/ipv6/mcast.c:1857
add_grec+0x1053/0x14e0 net/ipv6/mcast.c:1995
mld_send_initial_cr.part.0+0xf6/0x230 net/ipv6/mcast.c:2242
mld_send_initial_cr net/ipv6/mcast.c:1232 [inline]
mld_dad_work+0x1d3/0x690 net/ipv6/mcast.c:2268
process_one_work+0x9b2/0x1690 kernel/workqueue.c:2298
worker_thread+0x658/0x11f0 kernel/workqueue.c:2445
Memory state around the buggy address:
ffff88807f1cb600: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff88807f1cb680: fb fb fb fb fb fb fc fc fc fc fc fc fc fc fc fc
>ffff88807f1cb700: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
^
ffff88807f1cb780: fb fb fb fb fb fb fc fc fc fc fc fc fc fc fc fc
ffff88807f1cb800: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
Fixes: 41063e9dd119 ("ipv4: Early TCP socket demux.")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Link: https://lore.kernel.org/r/20211220143330.680945-1-eric.dumazet@gmail.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
[cmllamas: backported to 4.9; dropped irrelevant hunks in ipv6/udp.c;
added rcu_access_pointer(sk->sk_rx_dst) in tcp_prequeue().]
Signed-off-by: Carlos Llamas <cmllamas@google.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2022-10-26 13:15:48 +02:00
2022-08-25 11:09:20 +02:00
2021-06-10 12:42:36 +02:00
2015-09-21 16:03:04 -07:00
2022-03-08 19:00:57 +01:00
2019-08-25 10:51:42 +02:00
2021-12-08 08:45:04 +01:00
2019-03-23 13:19:44 +01:00
2021-09-26 13:36:19 +02:00
2018-08-24 13:12:37 +02:00
2016-06-15 20:41:22 -07:00
2020-06-03 08:16:25 +02:00
2020-08-21 11:01:55 +02:00
2015-09-17 13:20:05 +02:00
2016-09-08 11:10:12 +01:00
2021-08-04 11:58:01 +02:00
2018-08-22 07:47:13 +02:00
2019-06-11 12:22:49 +02:00
2019-02-23 09:05:59 +01:00
2016-02-09 04:45:49 -05:00
2015-07-27 01:05:24 -07:00
2020-12-11 13:37:57 +01:00
2022-09-05 10:23:55 +02:00
2016-06-27 15:06:17 -04:00
2021-06-03 08:23:28 +02:00
2016-07-08 12:20:57 +02:00
2022-03-02 11:32:02 +01:00
2017-02-18 15:11:41 +01:00
2016-04-19 20:09:25 -04:00
2016-04-25 16:44:27 -04:00
2016-06-25 12:19:35 -04:00
2016-04-25 16:44:27 -04:00
2016-06-09 23:41:03 -07:00
2016-08-26 11:55:18 -07:00
2015-09-17 17:18:37 -07:00
2016-09-23 08:38:50 -04:00
2016-02-16 20:21:48 -05:00
2022-02-16 12:43:54 +01:00
2015-10-08 04:27:02 -07:00
2020-07-22 09:10:48 +02:00
2015-09-23 15:33:15 -07:00
2020-03-20 09:07:39 +01:00
2020-03-11 07:53:05 +01:00
2016-09-10 23:12:53 -07:00
2016-05-20 18:03:16 -04:00
2019-11-10 11:23:31 +01:00
2019-11-10 11:23:31 +01:00
2016-06-07 16:37:14 -07:00
2020-07-22 09:10:48 +02:00
2016-06-17 20:23:32 -07:00
2016-08-18 01:17:32 -04:00
2019-03-19 13:14:10 +01:00
2016-07-25 17:55:43 -07:00
2016-03-14 12:19:46 -04:00
2021-03-03 17:44:46 +01:00
2016-09-12 11:45:45 +02:00
2022-10-26 13:15:48 +02:00
2016-10-14 10:59:15 -04:00
2015-12-15 23:25:20 -05:00
2016-03-22 15:45:44 -04:00
2016-04-04 22:11:20 -04:00
2016-05-20 18:03:17 -04:00
2020-09-12 11:47:38 +02:00
2020-12-11 13:37:58 +01:00
2019-05-02 09:32:06 +02:00
2022-06-25 11:45:19 +02:00
2022-07-29 17:05:45 +02:00
2018-05-16 10:08:41 +02:00
2019-02-23 09:05:59 +01:00
2016-03-13 23:55:13 -04:00
2017-09-20 08:19:53 +02:00
2021-07-28 09:14:25 +02:00
2019-07-21 09:05:57 +02:00
2019-01-31 08:12:33 +01:00
2016-09-17 10:13:07 -04:00
2019-11-12 19:15:57 +01:00
2022-07-29 17:05:45 +02:00
2019-09-16 08:19:33 +02:00
2020-05-20 08:15:30 +02:00
2017-08-11 08:49:34 -07:00
2016-08-17 19:36:23 -04:00
2019-02-06 17:33:27 +01:00
2019-11-06 12:18:24 +01:00
2021-08-04 11:58:03 +02:00
2021-11-26 11:48:39 +01:00
2017-02-18 15:11:42 +01:00
2018-05-30 07:50:28 +02:00
2016-07-08 13:23:12 +02:00
2015-10-23 06:26:42 -07:00
2016-10-03 02:00:22 -04:00
2016-10-04 02:11:51 -04:00
2016-06-15 20:41:23 -07:00
2020-01-12 11:24:19 +01:00
2019-04-17 08:36:46 +02:00
2016-07-05 09:06:29 -07:00
2016-06-27 15:06:18 -04:00
2017-10-12 11:51:25 +02:00
2015-12-08 22:02:33 -05:00
2018-05-16 10:08:41 +02:00
2021-12-08 08:45:03 +01:00
2016-03-23 22:09:58 -04:00
2016-09-28 05:02:44 -04:00
2016-08-10 17:19:02 -07:00
2016-08-15 10:55:53 -07:00
2016-04-07 16:53:30 -04:00
2016-02-11 03:54:14 -05:00
2021-04-16 11:59:07 +02:00
2018-05-30 07:50:30 +02:00
2016-04-04 22:11:19 -04:00
2018-05-30 07:50:36 +02:00
2021-03-30 14:41:42 +02:00
2022-01-27 08:47:42 +01:00
2016-02-08 10:30:42 -05:00
2022-06-25 11:45:19 +02:00
2018-04-20 08:21:07 +02:00
2016-04-28 11:49:45 -04:00
2016-01-19 14:44:23 -05:00
2022-10-26 13:15:48 +02:00
2016-08-28 23:32:41 -04:00
2016-09-28 04:48:00 -04:00
2022-10-26 13:15:40 +02:00
2015-07-09 15:12:20 -07:00
2016-05-03 16:08:14 -04:00
2015-10-26 22:24:22 -07:00
2016-06-17 20:23:32 -07:00
2016-10-20 14:45:52 -04:00
2018-03-11 16:21:32 +01:00
2017-07-21 07:42:18 +02:00
2018-04-13 19:48:00 +02:00
2022-04-20 09:06:44 +02:00
68c34ce11e