410 Commits

Author SHA1 Message Date
John Fastabend
90d1f74c3c bpf, sockmap: af_unix stream sockets need to hold ref for pair sock
[ Upstream commit 8866730aed5100f06d3d965c22f1c61f74942541 ]

AF_UNIX stream sockets are a paired socket. So sending on one of the pairs
will lookup the paired socket as part of the send operation. It is possible
however to put just one of the pairs in a BPF map. This currently increments
the refcnt on the sock in the sockmap to ensure it is not free'd by the
stack before sockmap cleans up its state and stops any skbs being sent/recv'd
to that socket.

But we missed a case. If the peer socket is closed it will be free'd by the
stack. However, the paired socket can still be referenced from BPF sockmap
side because we hold a reference there. Then if we are sending traffic through
BPF sockmap to that socket it will try to dereference the free'd pair in its
send logic creating a use after free. And following splat:

   [59.900375] BUG: KASAN: slab-use-after-free in sk_wake_async+0x31/0x1b0
   [59.901211] Read of size 8 at addr ffff88811acbf060 by task kworker/1:2/954
   [...]
   [59.905468] Call Trace:
   [59.905787]  <TASK>
   [59.906066]  dump_stack_lvl+0x130/0x1d0
   [59.908877]  print_report+0x16f/0x740
   [59.910629]  kasan_report+0x118/0x160
   [59.912576]  sk_wake_async+0x31/0x1b0
   [59.913554]  sock_def_readable+0x156/0x2a0
   [59.914060]  unix_stream_sendmsg+0x3f9/0x12a0
   [59.916398]  sock_sendmsg+0x20e/0x250
   [59.916854]  skb_send_sock+0x236/0xac0
   [59.920527]  sk_psock_backlog+0x287/0xaa0

To fix let BPF sockmap hold a refcnt on both the socket in the sockmap and its
paired socket. It wasn't obvious how to contain the fix to bpf_unix logic. The
primarily problem with keeping this logic in bpf_unix was: In the sock close()
we could handle the deref by having a close handler. But, when we are destroying
the psock through a map delete operation we wouldn't have gotten any signal
thorugh the proto struct other than it being replaced. If we do the deref from
the proto replace its too early because we need to deref the sk_pair after the
backlog worker has been stopped.

Given all this it seems best to just cache it at the end of the psock and eat 8B
for the af_unix and vsock users. Notice dgram sockets are OK because they handle
locking already.

Fixes: 94531cfcbe79 ("af_unix: Add unix_stream_proto for sockmap")
Signed-off-by: John Fastabend <john.fastabend@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Reviewed-by: Jakub Sitnicki <jakub@cloudflare.com>
Link: https://lore.kernel.org/bpf/20231129012557.95371-2-john.fastabend@gmail.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
2024-01-10 17:10:32 +01:00
Eric Dumazet
d179189eec af_unix: fix use-after-free in unix_stream_read_actor()
[ Upstream commit 4b7b492615cf3017190f55444f7016812b66611d ]

syzbot reported the following crash [1]

After releasing unix socket lock, u->oob_skb can be changed
by another thread. We must temporarily increase skb refcount
to make sure this other thread will not free the skb under us.

[1]

BUG: KASAN: slab-use-after-free in unix_stream_read_actor+0xa7/0xc0 net/unix/af_unix.c:2866
Read of size 4 at addr ffff88801f3b9cc4 by task syz-executor107/5297

CPU: 1 PID: 5297 Comm: syz-executor107 Not tainted 6.6.0-syzkaller-15910-gb8e3a87a627b #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/09/2023
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:88 [inline]
dump_stack_lvl+0xd9/0x1b0 lib/dump_stack.c:106
print_address_description mm/kasan/report.c:364 [inline]
print_report+0xc4/0x620 mm/kasan/report.c:475
kasan_report+0xda/0x110 mm/kasan/report.c:588
unix_stream_read_actor+0xa7/0xc0 net/unix/af_unix.c:2866
unix_stream_recv_urg net/unix/af_unix.c:2587 [inline]
unix_stream_read_generic+0x19a5/0x2480 net/unix/af_unix.c:2666
unix_stream_recvmsg+0x189/0x1b0 net/unix/af_unix.c:2903
sock_recvmsg_nosec net/socket.c:1044 [inline]
sock_recvmsg+0xe2/0x170 net/socket.c:1066
____sys_recvmsg+0x21f/0x5c0 net/socket.c:2803
___sys_recvmsg+0x115/0x1a0 net/socket.c:2845
__sys_recvmsg+0x114/0x1e0 net/socket.c:2875
do_syscall_x64 arch/x86/entry/common.c:51 [inline]
do_syscall_64+0x3f/0x110 arch/x86/entry/common.c:82
entry_SYSCALL_64_after_hwframe+0x63/0x6b
RIP: 0033:0x7fc67492c559
Code: 28 00 00 00 75 05 48 83 c4 28 c3 e8 51 18 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 b0 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007fc6748ab228 EFLAGS: 00000246 ORIG_RAX: 000000000000002f
RAX: ffffffffffffffda RBX: 000000000000001c RCX: 00007fc67492c559
RDX: 0000000040010083 RSI: 0000000020000140 RDI: 0000000000000004
RBP: 00007fc6749b6348 R08: 00007fc6748ab6c0 R09: 00007fc6748ab6c0
R10: 0000000000000000 R11: 0000000000000246 R12: 00007fc6749b6340
R13: 00007fc6749b634c R14: 00007ffe9fac52a0 R15: 00007ffe9fac5388
</TASK>

Allocated by task 5295:
kasan_save_stack+0x33/0x50 mm/kasan/common.c:45
kasan_set_track+0x25/0x30 mm/kasan/common.c:52
__kasan_slab_alloc+0x81/0x90 mm/kasan/common.c:328
kasan_slab_alloc include/linux/kasan.h:188 [inline]
slab_post_alloc_hook mm/slab.h:763 [inline]
slab_alloc_node mm/slub.c:3478 [inline]
kmem_cache_alloc_node+0x180/0x3c0 mm/slub.c:3523
__alloc_skb+0x287/0x330 net/core/skbuff.c:641
alloc_skb include/linux/skbuff.h:1286 [inline]
alloc_skb_with_frags+0xe4/0x710 net/core/skbuff.c:6331
sock_alloc_send_pskb+0x7e4/0x970 net/core/sock.c:2780
sock_alloc_send_skb include/net/sock.h:1884 [inline]
queue_oob net/unix/af_unix.c:2147 [inline]
unix_stream_sendmsg+0xb5f/0x10a0 net/unix/af_unix.c:2301
sock_sendmsg_nosec net/socket.c:730 [inline]
__sock_sendmsg+0xd5/0x180 net/socket.c:745
____sys_sendmsg+0x6ac/0x940 net/socket.c:2584
___sys_sendmsg+0x135/0x1d0 net/socket.c:2638
__sys_sendmsg+0x117/0x1e0 net/socket.c:2667
do_syscall_x64 arch/x86/entry/common.c:51 [inline]
do_syscall_64+0x3f/0x110 arch/x86/entry/common.c:82
entry_SYSCALL_64_after_hwframe+0x63/0x6b

Freed by task 5295:
kasan_save_stack+0x33/0x50 mm/kasan/common.c:45
kasan_set_track+0x25/0x30 mm/kasan/common.c:52
kasan_save_free_info+0x2b/0x40 mm/kasan/generic.c:522
____kasan_slab_free mm/kasan/common.c:236 [inline]
____kasan_slab_free+0x15b/0x1b0 mm/kasan/common.c:200
kasan_slab_free include/linux/kasan.h:164 [inline]
slab_free_hook mm/slub.c:1800 [inline]
slab_free_freelist_hook+0x114/0x1e0 mm/slub.c:1826
slab_free mm/slub.c:3809 [inline]
kmem_cache_free+0xf8/0x340 mm/slub.c:3831
kfree_skbmem+0xef/0x1b0 net/core/skbuff.c:1015
__kfree_skb net/core/skbuff.c:1073 [inline]
consume_skb net/core/skbuff.c:1288 [inline]
consume_skb+0xdf/0x170 net/core/skbuff.c:1282
queue_oob net/unix/af_unix.c:2178 [inline]
unix_stream_sendmsg+0xd49/0x10a0 net/unix/af_unix.c:2301
sock_sendmsg_nosec net/socket.c:730 [inline]
__sock_sendmsg+0xd5/0x180 net/socket.c:745
____sys_sendmsg+0x6ac/0x940 net/socket.c:2584
___sys_sendmsg+0x135/0x1d0 net/socket.c:2638
__sys_sendmsg+0x117/0x1e0 net/socket.c:2667
do_syscall_x64 arch/x86/entry/common.c:51 [inline]
do_syscall_64+0x3f/0x110 arch/x86/entry/common.c:82
entry_SYSCALL_64_after_hwframe+0x63/0x6b

The buggy address belongs to the object at ffff88801f3b9c80
which belongs to the cache skbuff_head_cache of size 240
The buggy address is located 68 bytes inside of
freed 240-byte region [ffff88801f3b9c80, ffff88801f3b9d70)

The buggy address belongs to the physical page:
page:ffffea00007cee40 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x1f3b9
flags: 0xfff00000000800(slab|node=0|zone=1|lastcpupid=0x7ff)
page_type: 0xffffffff()
raw: 00fff00000000800 ffff888142a60640 dead000000000122 0000000000000000
raw: 0000000000000000 00000000000c000c 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 0x12cc0(GFP_KERNEL|__GFP_NOWARN|__GFP_NORETRY), pid 5299, tgid 5283 (syz-executor107), ts 103803840339, free_ts 103600093431
set_page_owner include/linux/page_owner.h:31 [inline]
post_alloc_hook+0x2cf/0x340 mm/page_alloc.c:1537
prep_new_page mm/page_alloc.c:1544 [inline]
get_page_from_freelist+0xa25/0x36c0 mm/page_alloc.c:3312
__alloc_pages+0x1d0/0x4a0 mm/page_alloc.c:4568
alloc_pages_mpol+0x258/0x5f0 mm/mempolicy.c:2133
alloc_slab_page mm/slub.c:1870 [inline]
allocate_slab+0x251/0x380 mm/slub.c:2017
new_slab mm/slub.c:2070 [inline]
___slab_alloc+0x8c7/0x1580 mm/slub.c:3223
__slab_alloc.constprop.0+0x56/0xa0 mm/slub.c:3322
__slab_alloc_node mm/slub.c:3375 [inline]
slab_alloc_node mm/slub.c:3468 [inline]
kmem_cache_alloc_node+0x132/0x3c0 mm/slub.c:3523
__alloc_skb+0x287/0x330 net/core/skbuff.c:641
alloc_skb include/linux/skbuff.h:1286 [inline]
alloc_skb_with_frags+0xe4/0x710 net/core/skbuff.c:6331
sock_alloc_send_pskb+0x7e4/0x970 net/core/sock.c:2780
sock_alloc_send_skb include/net/sock.h:1884 [inline]
queue_oob net/unix/af_unix.c:2147 [inline]
unix_stream_sendmsg+0xb5f/0x10a0 net/unix/af_unix.c:2301
sock_sendmsg_nosec net/socket.c:730 [inline]
__sock_sendmsg+0xd5/0x180 net/socket.c:745
____sys_sendmsg+0x6ac/0x940 net/socket.c:2584
___sys_sendmsg+0x135/0x1d0 net/socket.c:2638
__sys_sendmsg+0x117/0x1e0 net/socket.c:2667
page last free stack trace:
reset_page_owner include/linux/page_owner.h:24 [inline]
free_pages_prepare mm/page_alloc.c:1137 [inline]
free_unref_page_prepare+0x4f8/0xa90 mm/page_alloc.c:2347
free_unref_page+0x33/0x3b0 mm/page_alloc.c:2487
__unfreeze_partials+0x21d/0x240 mm/slub.c:2655
qlink_free mm/kasan/quarantine.c:168 [inline]
qlist_free_all+0x6a/0x170 mm/kasan/quarantine.c:187
kasan_quarantine_reduce+0x18e/0x1d0 mm/kasan/quarantine.c:294
__kasan_slab_alloc+0x65/0x90 mm/kasan/common.c:305
kasan_slab_alloc include/linux/kasan.h:188 [inline]
slab_post_alloc_hook mm/slab.h:763 [inline]
slab_alloc_node mm/slub.c:3478 [inline]
slab_alloc mm/slub.c:3486 [inline]
__kmem_cache_alloc_lru mm/slub.c:3493 [inline]
kmem_cache_alloc+0x15d/0x380 mm/slub.c:3502
vm_area_dup+0x21/0x2f0 kernel/fork.c:500
__split_vma+0x17d/0x1070 mm/mmap.c:2365
split_vma mm/mmap.c:2437 [inline]
vma_modify+0x25d/0x450 mm/mmap.c:2472
vma_modify_flags include/linux/mm.h:3271 [inline]
mprotect_fixup+0x228/0xc80 mm/mprotect.c:635
do_mprotect_pkey+0x852/0xd60 mm/mprotect.c:809
__do_sys_mprotect mm/mprotect.c:830 [inline]
__se_sys_mprotect mm/mprotect.c:827 [inline]
__x64_sys_mprotect+0x78/0xb0 mm/mprotect.c:827
do_syscall_x64 arch/x86/entry/common.c:51 [inline]
do_syscall_64+0x3f/0x110 arch/x86/entry/common.c:82
entry_SYSCALL_64_after_hwframe+0x63/0x6b

Memory state around the buggy address:
ffff88801f3b9b80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
ffff88801f3b9c00: fb fb fb fb fb fb fc fc fc fc fc fc fc fc fc fc
>ffff88801f3b9c80: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
^
ffff88801f3b9d00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fc fc
ffff88801f3b9d80: fc fc fc fc fc fc fc fc fa fb fb fb fb fb fb fb

Fixes: 876c14ad014d ("af_unix: fix holding spinlock in oob handling")
Reported-and-tested-by: syzbot+7a2d546fa43e49315ed3@syzkaller.appspotmail.com
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Rao Shoaib <rao.shoaib@oracle.com>
Reviewed-by: Rao shoaib <rao.shoaib@oracle.com>
Link: https://lore.kernel.org/r/20231113134938.168151-1-edumazet@google.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-11-28 17:07:05 +00:00
Kuniyuki Iwashima
2d8933ca86 af_unix: Fix data-race around unix_tot_inflight.
[ Upstream commit ade32bd8a738d7497ffe9743c46728db26740f78 ]

unix_tot_inflight is changed under spin_lock(unix_gc_lock), but
unix_release_sock() reads it locklessly.

Let's use READ_ONCE() for unix_tot_inflight.

Note that the writer side was marked by commit 9d6d7f1cb67c ("af_unix:
annote lockless accesses to unix_tot_inflight & gc_in_progress")

BUG: KCSAN: data-race in unix_inflight / unix_release_sock

write (marked) to 0xffffffff871852b8 of 4 bytes by task 123 on cpu 1:
 unix_inflight+0x130/0x180 net/unix/scm.c:64
 unix_attach_fds+0x137/0x1b0 net/unix/scm.c:123
 unix_scm_to_skb net/unix/af_unix.c:1832 [inline]
 unix_dgram_sendmsg+0x46a/0x14f0 net/unix/af_unix.c:1955
 sock_sendmsg_nosec net/socket.c:724 [inline]
 sock_sendmsg+0x148/0x160 net/socket.c:747
 ____sys_sendmsg+0x4e4/0x610 net/socket.c:2493
 ___sys_sendmsg+0xc6/0x140 net/socket.c:2547
 __sys_sendmsg+0x94/0x140 net/socket.c:2576
 __do_sys_sendmsg net/socket.c:2585 [inline]
 __se_sys_sendmsg net/socket.c:2583 [inline]
 __x64_sys_sendmsg+0x45/0x50 net/socket.c:2583
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3b/0x90 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x72/0xdc

read to 0xffffffff871852b8 of 4 bytes by task 4891 on cpu 0:
 unix_release_sock+0x608/0x910 net/unix/af_unix.c:671
 unix_release+0x59/0x80 net/unix/af_unix.c:1058
 __sock_release+0x7d/0x170 net/socket.c:653
 sock_close+0x19/0x30 net/socket.c:1385
 __fput+0x179/0x5e0 fs/file_table.c:321
 ____fput+0x15/0x20 fs/file_table.c:349
 task_work_run+0x116/0x1a0 kernel/task_work.c:179
 resume_user_mode_work include/linux/resume_user_mode.h:49 [inline]
 exit_to_user_mode_loop kernel/entry/common.c:171 [inline]
 exit_to_user_mode_prepare+0x174/0x180 kernel/entry/common.c:204
 __syscall_exit_to_user_mode_work kernel/entry/common.c:286 [inline]
 syscall_exit_to_user_mode+0x1a/0x30 kernel/entry/common.c:297
 do_syscall_64+0x4b/0x90 arch/x86/entry/common.c:86
 entry_SYSCALL_64_after_hwframe+0x72/0xdc

value changed: 0x00000000 -> 0x00000001

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 4891 Comm: systemd-coredum Not tainted 6.4.0-rc5-01219-gfa0e21fa4443 #5
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.0-0-gd239552ce722-prebuilt.qemu.org 04/01/2014

Fixes: 9305cfa4443d ("[AF_UNIX]: Make unix_tot_inflight counter non-atomic")
Reported-by: syzkaller <syzkaller@googlegroups.com>
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.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>
2023-09-19 12:28:02 +02:00
Kuniyuki Iwashima
790c2f9d15 af_unix: Fix null-ptr-deref in unix_stream_sendpage().
Bing-Jhong Billy Jheng reported null-ptr-deref in unix_stream_sendpage()
with detailed analysis and a nice repro.

unix_stream_sendpage() tries to add data to the last skb in the peer's
recv queue without locking the queue.

If the peer's FD is passed to another socket and the socket's FD is
passed to the peer, there is a loop between them.  If we close both
sockets without receiving FD, the sockets will be cleaned up by garbage
collection.

The garbage collection iterates such sockets and unlinks skb with
FD from the socket's receive queue under the queue's lock.

So, there is a race where unix_stream_sendpage() could access an skb
locklessly that is being released by garbage collection, resulting in
use-after-free.

To avoid the issue, unix_stream_sendpage() must lock the peer's recv
queue.

Note the issue does not exist in 6.5+ thanks to the recent sendpage()
refactoring.

This patch is originally written by Linus Torvalds.

BUG: unable to handle page fault for address: ffff988004dd6870
PF: supervisor read access in kernel mode
PF: error_code(0x0000) - not-present page
PGD 0 P4D 0
PREEMPT SMP PTI
CPU: 4 PID: 297 Comm: garbage_uaf Not tainted 6.1.46 #1
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.0-0-gd239552ce722-prebuilt.qemu.org 04/01/2014
RIP: 0010:kmem_cache_alloc_node+0xa2/0x1e0
Code: c0 0f 84 32 01 00 00 41 83 fd ff 74 10 48 8b 00 48 c1 e8 3a 41 39 c5 0f 85 1c 01 00 00 41 8b 44 24 28 49 8b 3c 24 48 8d 4a 40 <49> 8b 1c 06 4c 89 f0 65 48 0f c7 0f 0f 94 c0 84 c0 74 a1 41 8b 44
RSP: 0018:ffffc9000079fac0 EFLAGS: 00000246
RAX: 0000000000000070 RBX: 0000000000000005 RCX: 000000000001a284
RDX: 000000000001a244 RSI: 0000000000400cc0 RDI: 000000000002eee0
RBP: 0000000000400cc0 R08: 0000000000400cc0 R09: 0000000000000003
R10: 0000000000000001 R11: 0000000000000000 R12: ffff888003970f00
R13: 00000000ffffffff R14: ffff988004dd6800 R15: 00000000000000e8
FS:  00007f174d6f3600(0000) GS:ffff88807db00000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: ffff988004dd6870 CR3: 00000000092be000 CR4: 00000000007506e0
PKRU: 55555554
Call Trace:
 <TASK>
 ? __die_body.cold+0x1a/0x1f
 ? page_fault_oops+0xa9/0x1e0
 ? fixup_exception+0x1d/0x310
 ? exc_page_fault+0xa8/0x150
 ? asm_exc_page_fault+0x22/0x30
 ? kmem_cache_alloc_node+0xa2/0x1e0
 ? __alloc_skb+0x16c/0x1e0
 __alloc_skb+0x16c/0x1e0
 alloc_skb_with_frags+0x48/0x1e0
 sock_alloc_send_pskb+0x234/0x270
 unix_stream_sendmsg+0x1f5/0x690
 sock_sendmsg+0x5d/0x60
 ____sys_sendmsg+0x210/0x260
 ___sys_sendmsg+0x83/0xd0
 ? kmem_cache_alloc+0xc6/0x1c0
 ? avc_disable+0x20/0x20
 ? percpu_counter_add_batch+0x53/0xc0
 ? alloc_empty_file+0x5d/0xb0
 ? alloc_file+0x91/0x170
 ? alloc_file_pseudo+0x94/0x100
 ? __fget_light+0x9f/0x120
 __sys_sendmsg+0x54/0xa0
 do_syscall_64+0x3b/0x90
 entry_SYSCALL_64_after_hwframe+0x69/0xd3
RIP: 0033:0x7f174d639a7d
Code: 28 89 54 24 1c 48 89 74 24 10 89 7c 24 08 e8 8a c1 f4 ff 8b 54 24 1c 48 8b 74 24 10 41 89 c0 8b 7c 24 08 b8 2e 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 33 44 89 c7 48 89 44 24 08 e8 de c1 f4 ff 48
RSP: 002b:00007ffcb563ea50 EFLAGS: 00000293 ORIG_RAX: 000000000000002e
RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f174d639a7d
RDX: 0000000000000000 RSI: 00007ffcb563eab0 RDI: 0000000000000007
RBP: 00007ffcb563eb10 R08: 0000000000000000 R09: 00000000ffffffff
R10: 00000000004040a0 R11: 0000000000000293 R12: 00007ffcb563ec28
R13: 0000000000401398 R14: 0000000000403e00 R15: 00007f174d72c000
 </TASK>

Fixes: 869e7c62486e ("net: af_unix: implement stream sendpage support")
Reported-by: Bing-Jhong Billy Jheng <billy@starlabs.sg>
Reviewed-by: Bing-Jhong Billy Jheng <billy@starlabs.sg>
Co-developed-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2023-08-23 17:52:42 +02:00
Eric Dumazet
dd7a1ff07c net: add missing data-race annotations around sk->sk_peek_off
[ Upstream commit 11695c6e966b0ec7ed1d16777d294cef865a5c91 ]

sk_getsockopt() runs locklessly, thus we need to annotate the read
of sk->sk_peek_off.

While we are at it, add corresponding annotations to sk_set_peek_off()
and unix_set_peek_off().

Fixes: b9bb53f3836f ("sock: convert sk_peek_offset functions to WRITE_ONCE")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Willem de Bruijn <willemb@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-08-11 12:08:14 +02:00
John Fastabend
4ae2af3e59 bpf, sockmap: Pass skb ownership through read_skb
[ Upstream commit 78fa0d61d97a728d306b0c23d353c0e340756437 ]

The read_skb hook calls consume_skb() now, but this means that if the
recv_actor program wants to use the skb it needs to inc the ref cnt
so that the consume_skb() doesn't kfree the sk_buff.

This is problematic because in some error cases under memory pressure
we may need to linearize the sk_buff from sk_psock_skb_ingress_enqueue().
Then we get this,

 skb_linearize()
   __pskb_pull_tail()
     pskb_expand_head()
       BUG_ON(skb_shared(skb))

Because we incremented users refcnt from sk_psock_verdict_recv() we
hit the bug on with refcnt > 1 and trip it.

To fix lets simply pass ownership of the sk_buff through the skb_read
call. Then we can drop the consume from read_skb handlers and assume
the verdict recv does any required kfree.

Bug found while testing in our CI which runs in VMs that hit memory
constraints rather regularly. William tested TCP read_skb handlers.

[  106.536188] ------------[ cut here ]------------
[  106.536197] kernel BUG at net/core/skbuff.c:1693!
[  106.536479] invalid opcode: 0000 [#1] PREEMPT SMP PTI
[  106.536726] CPU: 3 PID: 1495 Comm: curl Not tainted 5.19.0-rc5 #1
[  106.537023] Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS ArchLinux 1.16.0-1 04/01/2014
[  106.537467] RIP: 0010:pskb_expand_head+0x269/0x330
[  106.538585] RSP: 0018:ffffc90000138b68 EFLAGS: 00010202
[  106.538839] RAX: 000000000000003f RBX: ffff8881048940e8 RCX: 0000000000000a20
[  106.539186] RDX: 0000000000000002 RSI: 0000000000000000 RDI: ffff8881048940e8
[  106.539529] RBP: ffffc90000138be8 R08: 00000000e161fd1a R09: 0000000000000000
[  106.539877] R10: 0000000000000018 R11: 0000000000000000 R12: ffff8881048940e8
[  106.540222] R13: 0000000000000003 R14: 0000000000000000 R15: ffff8881048940e8
[  106.540568] FS:  00007f277dde9f00(0000) GS:ffff88813bd80000(0000) knlGS:0000000000000000
[  106.540954] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
[  106.541227] CR2: 00007f277eeede64 CR3: 000000000ad3e000 CR4: 00000000000006e0
[  106.541569] DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
[  106.541915] DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
[  106.542255] Call Trace:
[  106.542383]  <IRQ>
[  106.542487]  __pskb_pull_tail+0x4b/0x3e0
[  106.542681]  skb_ensure_writable+0x85/0xa0
[  106.542882]  sk_skb_pull_data+0x18/0x20
[  106.543084]  bpf_prog_b517a65a242018b0_bpf_skskb_http_verdict+0x3a9/0x4aa9
[  106.543536]  ? migrate_disable+0x66/0x80
[  106.543871]  sk_psock_verdict_recv+0xe2/0x310
[  106.544258]  ? sk_psock_write_space+0x1f0/0x1f0
[  106.544561]  tcp_read_skb+0x7b/0x120
[  106.544740]  tcp_data_queue+0x904/0xee0
[  106.544931]  tcp_rcv_established+0x212/0x7c0
[  106.545142]  tcp_v4_do_rcv+0x174/0x2a0
[  106.545326]  tcp_v4_rcv+0xe70/0xf60
[  106.545500]  ip_protocol_deliver_rcu+0x48/0x290
[  106.545744]  ip_local_deliver_finish+0xa7/0x150

Fixes: 04919bed948dc ("tcp: Introduce tcp_read_skb()")
Reported-by: William Findlay <will@isovalent.com>
Signed-off-by: John Fastabend <john.fastabend@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Tested-by: William Findlay <will@isovalent.com>
Reviewed-by: Jakub Sitnicki <jakub@cloudflare.com>
Link: https://lore.kernel.org/bpf/20230523025618.113937-2-john.fastabend@gmail.com
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-06-05 09:26:18 +02:00
Kuniyuki Iwashima
e410895892 af_unix: Fix data races around sk->sk_shutdown.
[ Upstream commit e1d09c2c2f5793474556b60f83900e088d0d366d ]

KCSAN found a data race around sk->sk_shutdown where unix_release_sock()
and unix_shutdown() update it under unix_state_lock(), OTOH unix_poll()
and unix_dgram_poll() read it locklessly.

We need to annotate the writes and reads with WRITE_ONCE() and READ_ONCE().

BUG: KCSAN: data-race in unix_poll / unix_release_sock

write to 0xffff88800d0f8aec of 1 bytes by task 264 on cpu 0:
 unix_release_sock+0x75c/0x910 net/unix/af_unix.c:631
 unix_release+0x59/0x80 net/unix/af_unix.c:1042
 __sock_release+0x7d/0x170 net/socket.c:653
 sock_close+0x19/0x30 net/socket.c:1397
 __fput+0x179/0x5e0 fs/file_table.c:321
 ____fput+0x15/0x20 fs/file_table.c:349
 task_work_run+0x116/0x1a0 kernel/task_work.c:179
 resume_user_mode_work include/linux/resume_user_mode.h:49 [inline]
 exit_to_user_mode_loop kernel/entry/common.c:171 [inline]
 exit_to_user_mode_prepare+0x174/0x180 kernel/entry/common.c:204
 __syscall_exit_to_user_mode_work kernel/entry/common.c:286 [inline]
 syscall_exit_to_user_mode+0x1a/0x30 kernel/entry/common.c:297
 do_syscall_64+0x4b/0x90 arch/x86/entry/common.c:86
 entry_SYSCALL_64_after_hwframe+0x72/0xdc

read to 0xffff88800d0f8aec of 1 bytes by task 222 on cpu 1:
 unix_poll+0xa3/0x2a0 net/unix/af_unix.c:3170
 sock_poll+0xcf/0x2b0 net/socket.c:1385
 vfs_poll include/linux/poll.h:88 [inline]
 ep_item_poll.isra.0+0x78/0xc0 fs/eventpoll.c:855
 ep_send_events fs/eventpoll.c:1694 [inline]
 ep_poll fs/eventpoll.c:1823 [inline]
 do_epoll_wait+0x6c4/0xea0 fs/eventpoll.c:2258
 __do_sys_epoll_wait fs/eventpoll.c:2270 [inline]
 __se_sys_epoll_wait fs/eventpoll.c:2265 [inline]
 __x64_sys_epoll_wait+0xcc/0x190 fs/eventpoll.c:2265
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3b/0x90 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x72/0xdc

value changed: 0x00 -> 0x03

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 222 Comm: dbus-broker Not tainted 6.3.0-rc7-02330-gca6270c12e20 #2
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.0-0-gd239552ce722-prebuilt.qemu.org 04/01/2014

Fixes: 3c73419c09a5 ("af_unix: fix 'poll for write'/ connected DGRAM sockets")
Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Reported-by: syzbot <syzkaller@googlegroups.com>
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Michal Kubiak <michal.kubiak@intel.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-05-24 17:32:33 +01:00
Kuniyuki Iwashima
75924fb0f3 af_unix: Fix a data race of sk->sk_receive_queue->qlen.
[ Upstream commit 679ed006d416ea0cecfe24a99d365d1dea69c683 ]

KCSAN found a data race of sk->sk_receive_queue->qlen where recvmsg()
updates qlen under the queue lock and sendmsg() checks qlen under
unix_state_sock(), not the queue lock, so the reader side needs
READ_ONCE().

BUG: KCSAN: data-race in __skb_try_recv_from_queue / unix_wait_for_peer

write (marked) to 0xffff888019fe7c68 of 4 bytes by task 49792 on cpu 0:
 __skb_unlink include/linux/skbuff.h:2347 [inline]
 __skb_try_recv_from_queue+0x3de/0x470 net/core/datagram.c:197
 __skb_try_recv_datagram+0xf7/0x390 net/core/datagram.c:263
 __unix_dgram_recvmsg+0x109/0x8a0 net/unix/af_unix.c:2452
 unix_dgram_recvmsg+0x94/0xa0 net/unix/af_unix.c:2549
 sock_recvmsg_nosec net/socket.c:1019 [inline]
 ____sys_recvmsg+0x3a3/0x3b0 net/socket.c:2720
 ___sys_recvmsg+0xc8/0x150 net/socket.c:2764
 do_recvmmsg+0x182/0x560 net/socket.c:2858
 __sys_recvmmsg net/socket.c:2937 [inline]
 __do_sys_recvmmsg net/socket.c:2960 [inline]
 __se_sys_recvmmsg net/socket.c:2953 [inline]
 __x64_sys_recvmmsg+0x153/0x170 net/socket.c:2953
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3b/0x90 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x72/0xdc

read to 0xffff888019fe7c68 of 4 bytes by task 49793 on cpu 1:
 skb_queue_len include/linux/skbuff.h:2127 [inline]
 unix_recvq_full net/unix/af_unix.c:229 [inline]
 unix_wait_for_peer+0x154/0x1a0 net/unix/af_unix.c:1445
 unix_dgram_sendmsg+0x13bc/0x14b0 net/unix/af_unix.c:2048
 sock_sendmsg_nosec net/socket.c:724 [inline]
 sock_sendmsg+0x148/0x160 net/socket.c:747
 ____sys_sendmsg+0x20e/0x620 net/socket.c:2503
 ___sys_sendmsg+0xc6/0x140 net/socket.c:2557
 __sys_sendmmsg+0x11d/0x370 net/socket.c:2643
 __do_sys_sendmmsg net/socket.c:2672 [inline]
 __se_sys_sendmmsg net/socket.c:2669 [inline]
 __x64_sys_sendmmsg+0x58/0x70 net/socket.c:2669
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x3b/0x90 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x72/0xdc

value changed: 0x0000000b -> 0x00000001

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 49793 Comm: syz-executor.0 Not tainted 6.3.0-rc7-02330-gca6270c12e20 #2
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.16.0-0-gd239552ce722-prebuilt.qemu.org 04/01/2014

Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Reported-by: syzbot <syzkaller@googlegroups.com>
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Michal Kubiak <michal.kubiak@intel.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-05-24 17:32:32 +01:00
Eric Dumazet
ac1968ac39 af_unix: fix struct pid leaks in OOB support
[ Upstream commit 2aab4b96900272885bc157f8b236abf1cdc02e08 ]

syzbot reported struct pid leak [1].

Issue is that queue_oob() calls maybe_add_creds() which potentially
holds a reference on a pid.

But skb->destructor is not set (either directly or by calling
unix_scm_to_skb())

This means that subsequent kfree_skb() or consume_skb() would leak
this reference.

In this fix, I chose to fully support scm even for the OOB message.

[1]
BUG: memory leak
unreferenced object 0xffff8881053e7f80 (size 128):
comm "syz-executor242", pid 5066, jiffies 4294946079 (age 13.220s)
hex dump (first 32 bytes):
01 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:
[<ffffffff812ae26a>] alloc_pid+0x6a/0x560 kernel/pid.c:180
[<ffffffff812718df>] copy_process+0x169f/0x26c0 kernel/fork.c:2285
[<ffffffff81272b37>] kernel_clone+0xf7/0x610 kernel/fork.c:2684
[<ffffffff812730cc>] __do_sys_clone+0x7c/0xb0 kernel/fork.c:2825
[<ffffffff849ad699>] do_syscall_x64 arch/x86/entry/common.c:50 [inline]
[<ffffffff849ad699>] do_syscall_64+0x39/0xb0 arch/x86/entry/common.c:80
[<ffffffff84a0008b>] entry_SYSCALL_64_after_hwframe+0x63/0xcd

Fixes: 314001f0bf92 ("af_unix: Add OOB support")
Reported-by: syzbot+7699d9e5635c10253a27@syzkaller.appspotmail.com
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Rao Shoaib <rao.shoaib@oracle.com>
Reviewed-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Link: https://lore.kernel.org/r/20230307164530.771896-1-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2023-03-17 08:50:28 +01:00
Kirill Tkhai
1d033ec2d1 unix: Fix race in SOCK_SEQPACKET's unix_dgram_sendmsg()
[ Upstream commit 3ff8bff704f4de125dca2262e5b5b963a3da1d87 ]

There is a race resulting in alive SOCK_SEQPACKET socket
may change its state from TCP_ESTABLISHED to TCP_CLOSE:

unix_release_sock(peer)                  unix_dgram_sendmsg(sk)
  sock_orphan(peer)
    sock_set_flag(peer, SOCK_DEAD)
                                           sock_alloc_send_pskb()
                                             if !(sk->sk_shutdown & SEND_SHUTDOWN)
                                               OK
                                           if sock_flag(peer, SOCK_DEAD)
                                             sk->sk_state = TCP_CLOSE
  sk->sk_shutdown = SHUTDOWN_MASK

After that socket sk remains almost normal: it is able to connect, listen, accept
and recvmsg, while it can't sendmsg.

Since this is the only possibility for alive SOCK_SEQPACKET to change
the state in such way, we should better fix this strange and potentially
danger corner case.

Note, that we will return EPIPE here like this is normally done in sock_alloc_send_pskb().
Originally used ECONNREFUSED looks strange, since it's strange to return
a specific retval in dependence of race in kernel, when user can't affect on this.

Also, move TCP_CLOSE assignment for SOCK_DGRAM sockets under state lock
to fix race with unix_dgram_connect():

unix_dgram_connect(other)            unix_dgram_sendmsg(sk)
                                       unix_peer(sk) = NULL
                                       unix_state_unlock(sk)
  unix_state_double_lock(sk, other)
  sk->sk_state  = TCP_ESTABLISHED
  unix_peer(sk) = other
  unix_state_double_unlock(sk, other)
                                       sk->sk_state  = TCP_CLOSED

This patch fixes both of these races.

Fixes: 83301b5367a9 ("af_unix: Set TCP_ESTABLISHED for datagram sockets too")
Signed-off-by: Kirill Tkhai <tkhai@ya.ru>
Link: https://lore.kernel.org/r/135fda25-22d5-837a-782b-ceee50e19844@ya.ru
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-12-31 13:32:54 +01:00
Yang Yingliang
99a75f34db af_unix: call proto_unregister() in the error path in af_unix_init()
[ Upstream commit 73e341e0281a35274629e9be27eae2f9b1b492bf ]

If register unix_stream_proto returns error, unix_dgram_proto needs
be unregistered.

Fixes: 94531cfcbe79 ("af_unix: Add unix_stream_proto for sockmap")
Signed-off-by: Yang Yingliang <yangyingliang@huawei.com>
Reviewed-by: Simon Horman <simon.horman@corigine.com>
Reviewed-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2022-12-31 13:32:27 +01:00
Jason A. Donenfeld
a251c17aa5 treewide: use get_random_u32() when possible
The prandom_u32() function has been a deprecated inline wrapper around
get_random_u32() for several releases now, and compiles down to the
exact same code. Replace the deprecated wrapper with a direct call to
the real function. The same also applies to get_random_int(), which is
just a wrapper around get_random_u32(). This was done as a basic find
and replace.

Reviewed-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Reviewed-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Yury Norov <yury.norov@gmail.com>
Reviewed-by: Jan Kara <jack@suse.cz> # for ext4
Acked-by: Toke Høiland-Jørgensen <toke@toke.dk> # for sch_cake
Acked-by: Chuck Lever <chuck.lever@oracle.com> # for nfsd
Acked-by: Jakub Kicinski <kuba@kernel.org>
Acked-by: Mika Westerberg <mika.westerberg@linux.intel.com> # for thunderbolt
Acked-by: Darrick J. Wong <djwong@kernel.org> # for xfs
Acked-by: Helge Deller <deller@gmx.de> # for parisc
Acked-by: Heiko Carstens <hca@linux.ibm.com> # for s390
Signed-off-by: Jason A. Donenfeld <Jason@zx2c4.com>
2022-10-11 17:42:58 -06:00
Linus Torvalds
30c999937f Scheduler changes for v6.1:
- Debuggability:
 
      - Change most occurances of BUG_ON() to WARN_ON_ONCE()
 
      - Reorganize & fix TASK_ state comparisons, turn it into a bitmap
 
      - Update/fix misc scheduler debugging facilities
 
  - Load-balancing & regular scheduling:
 
      - Improve the behavior of the scheduler in presence of lot of
        SCHED_IDLE tasks - in particular they should not impact other
        scheduling classes.
 
      - Optimize task load tracking, cleanups & fixes
 
      - Clean up & simplify misc load-balancing code
 
  - Freezer:
 
      - Rewrite the core freezer to behave better wrt thawing and be simpler
        in general, by replacing PF_FROZEN with TASK_FROZEN & fixing/adjusting
        all the fallout.
 
  - Deadline scheduler:
 
      - Fix the DL capacity-aware code
 
      - Factor out dl_task_is_earliest_deadline() & replenish_dl_new_period()
 
      - Relax/optimize locking in task_non_contending()
 
  - Cleanups:
 
      - Factor out the update_current_exec_runtime() helper
 
      - Various cleanups, simplifications
 
 Signed-off-by: Ingo Molnar <mingo@kernel.org>
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Merge tag 'sched-core-2022-10-07' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull scheduler updates from Ingo Molnar:
 "Debuggability:

   - Change most occurances of BUG_ON() to WARN_ON_ONCE()

   - Reorganize & fix TASK_ state comparisons, turn it into a bitmap

   - Update/fix misc scheduler debugging facilities

  Load-balancing & regular scheduling:

   - Improve the behavior of the scheduler in presence of lot of
     SCHED_IDLE tasks - in particular they should not impact other
     scheduling classes.

   - Optimize task load tracking, cleanups & fixes

   - Clean up & simplify misc load-balancing code

  Freezer:

   - Rewrite the core freezer to behave better wrt thawing and be
     simpler in general, by replacing PF_FROZEN with TASK_FROZEN &
     fixing/adjusting all the fallout.

  Deadline scheduler:

   - Fix the DL capacity-aware code

   - Factor out dl_task_is_earliest_deadline() &
     replenish_dl_new_period()

   - Relax/optimize locking in task_non_contending()

  Cleanups:

   - Factor out the update_current_exec_runtime() helper

   - Various cleanups, simplifications"

* tag 'sched-core-2022-10-07' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (41 commits)
  sched: Fix more TASK_state comparisons
  sched: Fix TASK_state comparisons
  sched/fair: Move call to list_last_entry() in detach_tasks
  sched/fair: Cleanup loop_max and loop_break
  sched/fair: Make sure to try to detach at least one movable task
  sched: Show PF_flag holes
  freezer,sched: Rewrite core freezer logic
  sched: Widen TAKS_state literals
  sched/wait: Add wait_event_state()
  sched/completion: Add wait_for_completion_state()
  sched: Add TASK_ANY for wait_task_inactive()
  sched: Change wait_task_inactive()s match_state
  freezer,umh: Clean up freezer/initrd interaction
  freezer: Have {,un}lock_system_sleep() save/restore flags
  sched: Rename task_running() to task_on_cpu()
  sched/fair: Cleanup for SIS_PROP
  sched/fair: Default to false in test_idle_cores()
  sched/fair: Remove useless check in select_idle_core()
  sched/fair: Avoid double search on same cpu
  sched/fair: Remove redundant check in select_idle_smt()
  ...
2022-10-10 09:10:28 -07:00
Jakub Kicinski
e52f7c1ddf Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Merge in the left-over fixes before the net-next pull-request.

Conflicts:

drivers/net/ethernet/mediatek/mtk_ppe.c
  ae3ed15da588 ("net: ethernet: mtk_eth_soc: fix state in __mtk_foe_entry_clear")
  9d8cb4c096ab ("net: ethernet: mtk_eth_soc: add foe_entry_size to mtk_eth_soc")
https://lore.kernel.org/all/6cb6893b-4921-a068-4c30-1109795110bb@tessares.net/

kernel/bpf/helpers.c
  8addbfc7b308 ("bpf: Gate dynptr API behind CAP_BPF")
  5679ff2f138f ("bpf: Move bpf_loop and bpf_for_each_map_elem under CAP_BPF")
  8a67f2de9b1d ("bpf: expose bpf_strtol and bpf_strtoul to all program types")
https://lore.kernel.org/all/20221003201957.13149-1-daniel@iogearbox.net/

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-10-03 17:44:18 -07:00
Kuniyuki Iwashima
7a62ed6136 af_unix: Fix memory leaks of the whole sk due to OOB skb.
syzbot reported a sequence of memory leaks, and one of them indicated we
failed to free a whole sk:

  unreferenced object 0xffff8880126e0000 (size 1088):
    comm "syz-executor419", pid 326, jiffies 4294773607 (age 12.609s)
    hex dump (first 32 bytes):
      00 00 00 00 00 00 00 00 7d 00 00 00 00 00 00 00  ........}.......
      01 00 07 40 00 00 00 00 00 00 00 00 00 00 00 00  ...@............
    backtrace:
      [<000000006fefe750>] sk_prot_alloc+0x64/0x2a0 net/core/sock.c:1970
      [<0000000074006db5>] sk_alloc+0x3b/0x800 net/core/sock.c:2029
      [<00000000728cd434>] unix_create1+0xaf/0x920 net/unix/af_unix.c:928
      [<00000000a279a139>] unix_create+0x113/0x1d0 net/unix/af_unix.c:997
      [<0000000068259812>] __sock_create+0x2ab/0x550 net/socket.c:1516
      [<00000000da1521e1>] sock_create net/socket.c:1566 [inline]
      [<00000000da1521e1>] __sys_socketpair+0x1a8/0x550 net/socket.c:1698
      [<000000007ab259e1>] __do_sys_socketpair net/socket.c:1751 [inline]
      [<000000007ab259e1>] __se_sys_socketpair net/socket.c:1748 [inline]
      [<000000007ab259e1>] __x64_sys_socketpair+0x97/0x100 net/socket.c:1748
      [<000000007dedddc1>] do_syscall_x64 arch/x86/entry/common.c:50 [inline]
      [<000000007dedddc1>] do_syscall_64+0x38/0x90 arch/x86/entry/common.c:80
      [<000000009456679f>] entry_SYSCALL_64_after_hwframe+0x63/0xcd

We can reproduce this issue by creating two AF_UNIX SOCK_STREAM sockets,
send()ing an OOB skb to each other, and close()ing them without consuming
the OOB skbs.

  int skpair[2];

  socketpair(AF_UNIX, SOCK_STREAM, 0, skpair);

  send(skpair[0], "x", 1, MSG_OOB);
  send(skpair[1], "x", 1, MSG_OOB);

  close(skpair[0]);
  close(skpair[1]);

Currently, we free an OOB skb in unix_sock_destructor() which is called via
__sk_free(), but it's too late because the receiver's unix_sk(sk)->oob_skb
is accounted against the sender's sk->sk_wmem_alloc and __sk_free() is
called only when sk->sk_wmem_alloc is 0.

In the repro sequences, we do not consume the OOB skb, so both two sk's
sock_put() never reach __sk_free() due to the positive sk->sk_wmem_alloc.
Then, no one can consume the OOB skb nor call __sk_free(), and we finally
leak the two whole sk.

Thus, we must free the unconsumed OOB skb earlier when close()ing the
socket.

Fixes: 314001f0bf92 ("af_unix: Add OOB support")
Reported-by: syzbot <syzkaller@googlegroups.com>
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2022-10-03 08:00:50 +01:00
Peilin Ye
d6e3b27cbd af_unix: Refactor unix_read_skb()
Similar to udp_read_skb(), delete the unnecessary while loop in
unix_read_skb() for readability.  Since recv_actor() cannot return a
value greater than skb->len (see sk_psock_verdict_recv()), remove the
redundant check.

Suggested-by: Cong Wang <cong.wang@bytedance.com>
Signed-off-by: Peilin Ye <peilin.ye@bytedance.com>
Link: https://lore.kernel.org/r/7009141683ad6cd3785daced3e4a80ba0eb773b5.1663909008.git.peilin.ye@bytedance.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-09-26 11:00:19 -07:00
Peter Zijlstra
f5d39b0208 freezer,sched: Rewrite core freezer logic
Rewrite the core freezer to behave better wrt thawing and be simpler
in general.

By replacing PF_FROZEN with TASK_FROZEN, a special block state, it is
ensured frozen tasks stay frozen until thawed and don't randomly wake
up early, as is currently possible.

As such, it does away with PF_FROZEN and PF_FREEZER_SKIP, freeing up
two PF_flags (yay!).

Specifically; the current scheme works a little like:

	freezer_do_not_count();
	schedule();
	freezer_count();

And either the task is blocked, or it lands in try_to_freezer()
through freezer_count(). Now, when it is blocked, the freezer
considers it frozen and continues.

However, on thawing, once pm_freezing is cleared, freezer_count()
stops working, and any random/spurious wakeup will let a task run
before its time.

That is, thawing tries to thaw things in explicit order; kernel
threads and workqueues before doing bringing SMP back before userspace
etc.. However due to the above mentioned races it is entirely possible
for userspace tasks to thaw (by accident) before SMP is back.

This can be a fatal problem in asymmetric ISA architectures (eg ARMv9)
where the userspace task requires a special CPU to run.

As said; replace this with a special task state TASK_FROZEN and add
the following state transitions:

	TASK_FREEZABLE	-> TASK_FROZEN
	__TASK_STOPPED	-> TASK_FROZEN
	__TASK_TRACED	-> TASK_FROZEN

The new TASK_FREEZABLE can be set on any state part of TASK_NORMAL
(IOW. TASK_INTERRUPTIBLE and TASK_UNINTERRUPTIBLE) -- any such state
is already required to deal with spurious wakeups and the freezer
causes one such when thawing the task (since the original state is
lost).

The special __TASK_{STOPPED,TRACED} states *can* be restored since
their canonical state is in ->jobctl.

With this, frozen tasks need an explicit TASK_FROZEN wakeup and are
free of undue (early / spurious) wakeups.

Signed-off-by: Peter Zijlstra (Intel) <peterz@infradead.org>
Reviewed-by: Ingo Molnar <mingo@kernel.org>
Acked-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
Link: https://lore.kernel.org/r/20220822114649.055452969@infradead.org
2022-09-07 21:53:50 +02:00
Kirill Tkhai
de43708924 af_unix: Show number of inflight fds for sockets in TCP_LISTEN state too
TCP_LISTEN sockets is a special case. They preserve skb with a newly
connected sock till accept() makes it fully functional socket.
Receive queue of such socket may grow after connected peer
send messages there. Since these messages may contain scm_fds,
we should expose correct fdinfo::scm_fds for listening socket too.

Signed-off-by: Kirill Tkhai <tkhai@ya.ru>
Signed-off-by: David S. Miller <davem@davemloft.net>
2022-08-22 11:34:54 +01:00
Jakub Kicinski
0076cad301 Merge https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next
Daniel Borkmann says:

====================
pull-request: bpf-next 2022-07-09

We've added 94 non-merge commits during the last 19 day(s) which contain
a total of 125 files changed, 5141 insertions(+), 6701 deletions(-).

The main changes are:

1) Add new way for performing BTF type queries to BPF, from Daniel Müller.

2) Add inlining of calls to bpf_loop() helper when its function callback is
   statically known, from Eduard Zingerman.

3) Implement BPF TCP CC framework usability improvements, from Jörn-Thorben Hinz.

4) Add LSM flavor for attaching per-cgroup BPF programs to existing LSM
   hooks, from Stanislav Fomichev.

5) Remove all deprecated libbpf APIs in prep for 1.0 release, from Andrii Nakryiko.

6) Add benchmarks around local_storage to BPF selftests, from Dave Marchevsky.

7) AF_XDP sample removal (given move to libxdp) and various improvements around AF_XDP
   selftests, from Magnus Karlsson & Maciej Fijalkowski.

8) Add bpftool improvements for memcg probing and bash completion, from Quentin Monnet.

9) Add arm64 JIT support for BPF-2-BPF coupled with tail calls, from Jakub Sitnicki.

10) Sockmap optimizations around throughput of UDP transmissions which have been
    improved by 61%, from Cong Wang.

11) Rework perf's BPF prologue code to remove deprecated functions, from Jiri Olsa.

12) Fix sockmap teardown path to avoid sleepable sk_psock_stop, from John Fastabend.

13) Fix libbpf's cleanup around legacy kprobe/uprobe on error case, from Chuang Wang.

14) Fix libbpf's bpf_helpers.h to work with gcc for the case of its sec/pragma
    macro, from James Hilliard.

15) Fix libbpf's pt_regs macros for riscv to use a0 for RC register, from Yixun Lan.

16) Fix bpftool to show the name of type BPF_OBJ_LINK, from Yafang Shao.

* https://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf-next: (94 commits)
  selftests/bpf: Fix xdp_synproxy build failure if CONFIG_NF_CONNTRACK=m/n
  bpf: Correctly propagate errors up from bpf_core_composites_match
  libbpf: Disable SEC pragma macro on GCC
  bpf: Check attach_func_proto more carefully in check_return_code
  selftests/bpf: Add test involving restrict type qualifier
  bpftool: Add support for KIND_RESTRICT to gen min_core_btf command
  MAINTAINERS: Add entry for AF_XDP selftests files
  selftests, xsk: Rename AF_XDP testing app
  bpf, docs: Remove deprecated xsk libbpf APIs description
  selftests/bpf: Add benchmark for local_storage RCU Tasks Trace usage
  libbpf, riscv: Use a0 for RC register
  libbpf: Remove unnecessary usdt_rel_ip assignments
  selftests/bpf: Fix few more compiler warnings
  selftests/bpf: Fix bogus uninitialized variable warning
  bpftool: Remove zlib feature test from Makefile
  libbpf: Cleanup the legacy uprobe_event on failed add/attach_event()
  libbpf: Fix wrong variable used in perf_event_uprobe_open_legacy()
  libbpf: Cleanup the legacy kprobe_event on failed add/attach_event()
  selftests/bpf: Add type match test against kernel's task_struct
  selftests/bpf: Add nested type to type based tests
  ...
====================

Link: https://lore.kernel.org/r/20220708233145.32365-1-daniel@iogearbox.net
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-07-09 12:24:16 -07:00
Kuniyuki Iwashima
cf21b355cc af_unix: Optimise hash table layout.
Commit 6dd4142fb5a9 ("Merge branch 'af_unix-per-netns-socket-hash'") and
commit 51bae889fe11 ("af_unix: Put pathname sockets in the global hash
table.") changed a hash table layout.

  Before:
    unix_socket_table [0   - 255] : abstract & pathname sockets
                      [256 - 511] : unnamed sockets

  After:
    per-netns table   [0   - 255] : abstract & pathname sockets
                      [256 - 511] : unnamed sockets
    bsd_socket_table  [0   - 255] : pathname sockets (sk_bind_node)

Now, while looking up sockets, we traverse the global table for the
pathname sockets and the first half of each per-netns hash table for
abstract sockets, where pathname sockets are also linked.  Thus, the
more pathname sockets we have, the longer we take to look up abstract
sockets.  This characteristic has been there before the layout change,
but we can improve it now.

This patch changes the per-netns hash table's layout so that sockets not
requiring lookup reside in the first half and do not impact the lookup of
abstract sockets.

    per-netns table   [0   - 255] : pathname & unnamed sockets
                      [256 - 511] : abstract sockets
    bsd_socket_table  [0   - 255] : pathname sockets (sk_bind_node)

We have run a test that bind()s 100,000 abstract/pathname sockets for
each, bind()s an abstract socket 100,000 times and measures the time
on __unix_find_socket_byname().  The result shows that the patch makes
each lookup faster.

  Without this patch:
    $ sudo ./funclatency -p 2278 --microseconds __unix_find_socket_byname.isra.44
     usec                : count    distribution
         0 -> 1          : 0        |                                        |
         2 -> 3          : 0        |                                        |
         4 -> 7          : 0        |                                        |
         8 -> 15         : 126      |                                        |
        16 -> 31         : 1438     |*                                       |
        32 -> 63         : 4150     |***                                     |
        64 -> 127        : 9049     |*******                                 |
       128 -> 255        : 37704    |*******************************         |
       256 -> 511        : 47533    |****************************************|

  With this patch:
    $ sudo ./funclatency -p 3648 --microseconds __unix_find_socket_byname.isra.46
     usec                : count    distribution
         0 -> 1          : 109      |                                        |
         2 -> 3          : 318      |                                        |
         4 -> 7          : 725      |                                        |
         8 -> 15         : 2501     |*                                       |
        16 -> 31         : 3061     |**                                      |
        32 -> 63         : 4028     |***                                     |
        64 -> 127        : 9312     |*******                                 |
       128 -> 255        : 51372    |****************************************|
       256 -> 511        : 28574    |**********************                  |

Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Link: https://lore.kernel.org/r/20220705233715.759-1-kuniyu@amazon.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2022-07-07 13:19:01 +02:00
Kuniyuki Iwashima
51bae889fe af_unix: Put pathname sockets in the global hash table.
Commit cf2f225e2653 ("af_unix: Put a socket into a per-netns hash table.")
accidentally broke user API for pathname sockets.  A socket was able to
connect() to a pathname socket whose file was visible even if they were in
different network namespaces.

The commit puts all sockets into a per-netns hash table.  As a result,
connect() to a pathname socket in a different netns fails to find it in the
caller's per-netns hash table and returns -ECONNREFUSED even when the task
can view the peer socket file.

We can reproduce this issue by:

  Console A:

    # python3
    >>> from socket import *
    >>> s = socket(AF_UNIX, SOCK_STREAM, 0)
    >>> s.bind('test')
    >>> s.listen(32)

  Console B:

    # ip netns add test
    # ip netns exec test sh
    # python3
    >>> from socket import *
    >>> s = socket(AF_UNIX, SOCK_STREAM, 0)
    >>> s.connect('test')

Note when dumping sockets by sock_diag, procfs, and bpf_iter, they are
filtered only by netns.  In other words, even if they are visible and
connect()able, all sockets in different netns are skipped while iterating
sockets.  Thus, we need a fix only for finding a peer pathname socket.

This patch adds a global hash table for pathname sockets, links them with
sk_bind_node, and uses it in unix_find_socket_byinode().  By doing so, we
can keep sockets in per-netns hash tables and dump them easily.

Thanks to Sachin Sant and Leonard Crestez for reports, logs and a reproducer.

Fixes: cf2f225e2653 ("af_unix: Put a socket into a per-netns hash table.")
Reported-by: Sachin Sant <sachinp@linux.ibm.com>
Reported-by: Leonard Crestez <cdleonard@gmail.com>
Tested-by: Sachin Sant <sachinp@linux.ibm.com>
Tested-by: Nathan Chancellor <nathan@kernel.org>
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Tested-by: Leonard Crestez <cdleonard@gmail.com>
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2022-07-05 11:34:58 +02:00
Kuniyuki Iwashima
2f7ca90a01 af_unix: Remove unix_table_locks.
unix_table_locks are to protect the global hash table, unix_socket_table.
The previous commit removed it, so let's clean up the unnecessary locks.

Here is a test result on EC2 c5.9xlarge where 10 processes run concurrently
in different netns and bind 100,000 sockets for each.

  without this series : 1m 38s
  with this series    :    11s

It is ~10x faster because the global hash table is split into 10 netns in
this case.

Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2022-06-22 12:59:43 +01:00
Kuniyuki Iwashima
cf2f225e26 af_unix: Put a socket into a per-netns hash table.
This commit replaces the global hash table with a per-netns one and removes
the global one.

We now link a socket in each netns's hash table so we can save some netns
comparisons when iterating through a hash bucket.

Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2022-06-22 12:59:43 +01:00
Kuniyuki Iwashima
79b05beaa5 af_unix: Acquire/Release per-netns hash table's locks.
This commit adds extra spin_lock/spin_unlock() for a per-netns
hash table inside the existing ones for unix_table_locks.

As of this commit, sockets are still linked in the global hash
table.  After putting sockets in a per-netns hash table and
removing the old one in the next patch, we remove the global
locks in the last patch.

Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2022-06-22 12:59:43 +01:00
Kuniyuki Iwashima
b6e8113830 af_unix: Define a per-netns hash table.
This commit adds a per netns hash table for AF_UNIX, which size is fixed
as UNIX_HASH_SIZE for now.

The first implementation defines a per-netns hash table as a single array
of lock and list:

	struct unix_hashbucket {
		spinlock_t		lock;
		struct hlist_head	head;
	};

	struct netns_unix {
		struct unix_hashbucket	*hash;
		...
	};

But, Eric pointed out memory cost that the structure has holes because of
sizeof(spinlock_t), which is 4 (or more if LOCKDEP is enabled). [0]  It
could be expensive on a host with thousands of netns and few AF_UNIX
sockets.  For this reason, a per-netns hash table uses two dense arrays.

	struct unix_table {
		spinlock_t		*locks;
		struct hlist_head	*buckets;
	};

	struct netns_unix {
		struct unix_table	table;
		...
	};

Note the length of the list has a significant impact rather than lock
contention, so having shared locks can be an option.  But, per-netns
locks and lists still perform better than the global locks and per-netns
lists. [1]

Also, this patch adds a change so that struct netns_unix disappears from
struct net if CONFIG_UNIX is disabled.

[0]: https://lore.kernel.org/netdev/CANn89iLVxO5aqx16azNU7p7Z-nz5NrnM5QTqOzueVxEnkVTxyg@mail.gmail.com/
[1]: https://lore.kernel.org/netdev/20220617175215.1769-1-kuniyu@amazon.com/

Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2022-06-22 12:59:43 +01:00
Kuniyuki Iwashima
f302d180c6 af_unix: Include the whole hash table size in UNIX_HASH_SIZE.
Currently, the size of AF_UNIX hash table is UNIX_HASH_SIZE * 2,
the first half for bind()ed sockets and the second half for unbound
ones.  UNIX_HASH_SIZE * 2 is used to define the table and iterate
over it.

In some places, we use ARRAY_SIZE(unix_socket_table) instead of
UNIX_HASH_SIZE * 2.  However, we cannot use it anymore because we
will allocate the hash table dynamically.  Then, we would have to
add UNIX_HASH_SIZE * 2 in many places, which would be troublesome.

This patch adapts the UNIX_HASH_SIZE definition to include bound
and unbound sockets and defines a new UNIX_HASH_MOD macro to ease
calculations.

Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2022-06-22 12:59:43 +01:00
Kuniyuki Iwashima
340c3d3371 af_unix: Clean up some sock_net() uses.
Some functions define a net pointer only for one-shot use.  Others call
sock_net() redundantly even when a net pointer is available.  Let's fix
these and make the code simpler.

Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2022-06-22 12:59:43 +01:00
Cong Wang
965b57b469 net: Introduce a new proto_ops ->read_skb()
Currently both splice() and sockmap use ->read_sock() to
read skb from receive queue, but for sockmap we only read
one entire skb at a time, so ->read_sock() is too conservative
to use. Introduce a new proto_ops ->read_skb() which supports
this sematic, with this we can finally pass the ownership of
skb to recv actors.

For non-TCP protocols, all ->read_sock() can be simply
converted to ->read_skb().

Signed-off-by: Cong Wang <cong.wang@bytedance.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Reviewed-by: John Fastabend <john.fastabend@gmail.com>
Link: https://lore.kernel.org/bpf/20220615162014.89193-3-xiyou.wangcong@gmail.com
2022-06-20 14:05:52 +02:00
Eric Dumazet
dd29c67dbb af_unix: use DEBUG_NET_WARN_ON_ONCE()
Replace four WARN_ON() that have not triggered recently
with DEBUG_NET_WARN_ON_ONCE().

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-06-09 21:53:56 -07:00
Kuniyuki Iwashima
662a80946c af_unix: Fix a data-race in unix_dgram_peer_wake_me().
unix_dgram_poll() calls unix_dgram_peer_wake_me() without `other`'s
lock held and check if its receive queue is full.  Here we need to
use unix_recvq_full_lockless() instead of unix_recvq_full(), otherwise
KCSAN will report a data-race.

Fixes: 7d267278a9ec ("unix: avoid use-after-free in ep_remove_wait_queue")
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Link: https://lore.kernel.org/r/20220605232325.11804-1-kuniyu@amazon.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2022-06-07 12:07:46 +02:00
Linus Torvalds
7e062cda7d Networking changes for 5.19.
Core
 ----
 
  - Support TCPv6 segmentation offload with super-segments larger than
    64k bytes using the IPv6 Jumbogram extension header (AKA BIG TCP).
 
  - Generalize skb freeing deferral to per-cpu lists, instead of
    per-socket lists.
 
  - Add a netdev statistic for packets dropped due to L2 address
    mismatch (rx_otherhost_dropped).
 
  - Continue work annotating skb drop reasons.
 
  - Accept alternative netdev names (ALT_IFNAME) in more netlink
    requests.
 
  - Add VLAN support for AF_PACKET SOCK_RAW GSO.
 
  - Allow receiving skb mark from the socket as a cmsg.
 
  - Enable memcg accounting for veth queues, sysctl tables and IPv6.
 
 BPF
 ---
 
  - Add libbpf support for User Statically-Defined Tracing (USDTs).
 
  - Speed up symbol resolution for kprobes multi-link attachments.
 
  - Support storing typed pointers to referenced and unreferenced
    objects in BPF maps.
 
  - Add support for BPF link iterator.
 
  - Introduce access to remote CPU map elements in BPF per-cpu map.
 
  - Allow middle-of-the-road settings for the
    kernel.unprivileged_bpf_disabled sysctl.
 
  - Implement basic types of dynamic pointers e.g. to allow for
    dynamically sized ringbuf reservations without extra memory copies.
 
 Protocols
 ---------
 
  - Retire port only listening_hash table, add a second bind table
    hashed by port and address. Avoid linear list walk when binding
    to very popular ports (e.g. 443).
 
  - Add bridge FDB bulk flush filtering support allowing user space
    to remove all FDB entries matching a condition.
 
  - Introduce accept_unsolicited_na sysctl for IPv6 to implement
    router-side changes for RFC9131.
 
  - Support for MPTCP path manager in user space.
 
  - Add MPTCP support for fallback to regular TCP for connections
    that have never connected additional subflows or transmitted
    out-of-sequence data (partial support for RFC8684 fallback).
 
  - Avoid races in MPTCP-level window tracking, stabilize and improve
    throughput.
 
  - Support lockless operation of GRE tunnels with seq numbers enabled.
 
  - WiFi support for host based BSS color collision detection.
 
  - Add support for SO_TXTIME/SCM_TXTIME on CAN sockets.
 
  - Support transmission w/o flow control in CAN ISOTP (ISO 15765-2).
 
  - Support zero-copy Tx with TLS 1.2 crypto offload (sendfile).
 
  - Allow matching on the number of VLAN tags via tc-flower.
 
  - Add tracepoint for tcp_set_ca_state().
 
 Driver API
 ----------
 
  - Improve error reporting from classifier and action offload.
 
  - Add support for listing line cards in switches (devlink).
 
  - Add helpers for reporting page pool statistics with ethtool -S.
 
  - Add support for reading clock cycles when using PTP virtual clocks,
    instead of having the driver convert to time before reporting.
    This makes it possible to report time from different vclocks.
 
  - Support configuring low-latency Tx descriptor push via ethtool.
 
  - Separate Clause 22 and Clause 45 MDIO accesses more explicitly.
 
 New hardware / drivers
 ----------------------
 
  - Ethernet:
    - Marvell's Octeon NIC PCI Endpoint support (octeon_ep)
    - Sunplus SP7021 SoC (sp7021_emac)
    - Add support for Renesas RZ/V2M (in ravb)
    - Add support for MediaTek mt7986 switches (in mtk_eth_soc)
 
  - Ethernet PHYs:
    - ADIN1100 industrial PHYs (w/ 10BASE-T1L and SQI reporting)
    - TI DP83TD510 PHY
    - Microchip LAN8742/LAN88xx PHYs
 
  - WiFi:
    - Driver for pureLiFi X, XL, XC devices (plfxlc)
    - Driver for Silicon Labs devices (wfx)
    - Support for WCN6750 (in ath11k)
    - Support Realtek 8852ce devices (in rtw89)
 
  - Mobile:
    - MediaTek T700 modems (Intel 5G 5000 M.2 cards)
 
  - CAN:
   - ctucanfd: add support for CTU CAN FD open-source IP core
     from Czech Technical University in Prague
 
 Drivers
 -------
 
  - Delete a number of old drivers still using virt_to_bus().
 
  - Ethernet NICs:
    - intel: support TSO on tunnels MPLS
    - broadcom: support multi-buffer XDP
    - nfp: support VF rate limiting
    - sfc: use hardware tx timestamps for more than PTP
    - mlx5: multi-port eswitch support
    - hyper-v: add support for XDP_REDIRECT
    - atlantic: XDP support (including multi-buffer)
    - macb: improve real-time perf by deferring Tx processing to NAPI
 
  - High-speed Ethernet switches:
    - mlxsw: implement basic line card information querying
    - prestera: add support for traffic policing on ingress and egress
 
  - Embedded Ethernet switches:
    - lan966x: add support for packet DMA (FDMA)
    - lan966x: add support for PTP programmable pins
    - ti: cpsw_new: enable bc/mc storm prevention
 
  - Qualcomm 802.11ax WiFi (ath11k):
    - Wake-on-WLAN support for QCA6390 and WCN6855
    - device recovery (firmware restart) support
    - support setting Specific Absorption Rate (SAR) for WCN6855
    - read country code from SMBIOS for WCN6855/QCA6390
    - enable keep-alive during WoWLAN suspend
    - implement remain-on-channel support
 
  - MediaTek WiFi (mt76):
    - support Wireless Ethernet Dispatch offloading packet movement
      between the Ethernet switch and WiFi interfaces
    - non-standard VHT MCS10-11 support
    - mt7921 AP mode support
    - mt7921 IPv6 NS offload support
 
  - Ethernet PHYs:
    - micrel: ksz9031/ksz9131: cabletest support
    - lan87xx: SQI support for T1 PHYs
    - lan937x: add interrupt support for link detection
 
 Signed-off-by: Jakub Kicinski <kuba@kernel.org>
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Merge tag 'net-next-5.19' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next

Pull networking updates from Jakub Kicinski:
 "Core
  ----

   - Support TCPv6 segmentation offload with super-segments larger than
     64k bytes using the IPv6 Jumbogram extension header (AKA BIG TCP).

   - Generalize skb freeing deferral to per-cpu lists, instead of
     per-socket lists.

   - Add a netdev statistic for packets dropped due to L2 address
     mismatch (rx_otherhost_dropped).

   - Continue work annotating skb drop reasons.

   - Accept alternative netdev names (ALT_IFNAME) in more netlink
     requests.

   - Add VLAN support for AF_PACKET SOCK_RAW GSO.

   - Allow receiving skb mark from the socket as a cmsg.

   - Enable memcg accounting for veth queues, sysctl tables and IPv6.

  BPF
  ---

   - Add libbpf support for User Statically-Defined Tracing (USDTs).

   - Speed up symbol resolution for kprobes multi-link attachments.

   - Support storing typed pointers to referenced and unreferenced
     objects in BPF maps.

   - Add support for BPF link iterator.

   - Introduce access to remote CPU map elements in BPF per-cpu map.

   - Allow middle-of-the-road settings for the
     kernel.unprivileged_bpf_disabled sysctl.

   - Implement basic types of dynamic pointers e.g. to allow for
     dynamically sized ringbuf reservations without extra memory copies.

  Protocols
  ---------

   - Retire port only listening_hash table, add a second bind table
     hashed by port and address. Avoid linear list walk when binding to
     very popular ports (e.g. 443).

   - Add bridge FDB bulk flush filtering support allowing user space to
     remove all FDB entries matching a condition.

   - Introduce accept_unsolicited_na sysctl for IPv6 to implement
     router-side changes for RFC9131.

   - Support for MPTCP path manager in user space.

   - Add MPTCP support for fallback to regular TCP for connections that
     have never connected additional subflows or transmitted
     out-of-sequence data (partial support for RFC8684 fallback).

   - Avoid races in MPTCP-level window tracking, stabilize and improve
     throughput.

   - Support lockless operation of GRE tunnels with seq numbers enabled.

   - WiFi support for host based BSS color collision detection.

   - Add support for SO_TXTIME/SCM_TXTIME on CAN sockets.

   - Support transmission w/o flow control in CAN ISOTP (ISO 15765-2).

   - Support zero-copy Tx with TLS 1.2 crypto offload (sendfile).

   - Allow matching on the number of VLAN tags via tc-flower.

   - Add tracepoint for tcp_set_ca_state().

  Driver API
  ----------

   - Improve error reporting from classifier and action offload.

   - Add support for listing line cards in switches (devlink).

   - Add helpers for reporting page pool statistics with ethtool -S.

   - Add support for reading clock cycles when using PTP virtual clocks,
     instead of having the driver convert to time before reporting. This
     makes it possible to report time from different vclocks.

   - Support configuring low-latency Tx descriptor push via ethtool.

   - Separate Clause 22 and Clause 45 MDIO accesses more explicitly.

  New hardware / drivers
  ----------------------

   - Ethernet:
      - Marvell's Octeon NIC PCI Endpoint support (octeon_ep)
      - Sunplus SP7021 SoC (sp7021_emac)
      - Add support for Renesas RZ/V2M (in ravb)
      - Add support for MediaTek mt7986 switches (in mtk_eth_soc)

   - Ethernet PHYs:
      - ADIN1100 industrial PHYs (w/ 10BASE-T1L and SQI reporting)
      - TI DP83TD510 PHY
      - Microchip LAN8742/LAN88xx PHYs

   - WiFi:
      - Driver for pureLiFi X, XL, XC devices (plfxlc)
      - Driver for Silicon Labs devices (wfx)
      - Support for WCN6750 (in ath11k)
      - Support Realtek 8852ce devices (in rtw89)

   - Mobile:
      - MediaTek T700 modems (Intel 5G 5000 M.2 cards)

   - CAN:
      - ctucanfd: add support for CTU CAN FD open-source IP core from
        Czech Technical University in Prague

  Drivers
  -------

   - Delete a number of old drivers still using virt_to_bus().

   - Ethernet NICs:
      - intel: support TSO on tunnels MPLS
      - broadcom: support multi-buffer XDP
      - nfp: support VF rate limiting
      - sfc: use hardware tx timestamps for more than PTP
      - mlx5: multi-port eswitch support
      - hyper-v: add support for XDP_REDIRECT
      - atlantic: XDP support (including multi-buffer)
      - macb: improve real-time perf by deferring Tx processing to NAPI

   - High-speed Ethernet switches:
      - mlxsw: implement basic line card information querying
      - prestera: add support for traffic policing on ingress and egress

   - Embedded Ethernet switches:
      - lan966x: add support for packet DMA (FDMA)
      - lan966x: add support for PTP programmable pins
      - ti: cpsw_new: enable bc/mc storm prevention

   - Qualcomm 802.11ax WiFi (ath11k):
      - Wake-on-WLAN support for QCA6390 and WCN6855
      - device recovery (firmware restart) support
      - support setting Specific Absorption Rate (SAR) for WCN6855
      - read country code from SMBIOS for WCN6855/QCA6390
      - enable keep-alive during WoWLAN suspend
      - implement remain-on-channel support

   - MediaTek WiFi (mt76):
      - support Wireless Ethernet Dispatch offloading packet movement
        between the Ethernet switch and WiFi interfaces
      - non-standard VHT MCS10-11 support
      - mt7921 AP mode support
      - mt7921 IPv6 NS offload support

   - Ethernet PHYs:
      - micrel: ksz9031/ksz9131: cabletest support
      - lan87xx: SQI support for T1 PHYs
      - lan937x: add interrupt support for link detection"

* tag 'net-next-5.19' of git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net-next: (1809 commits)
  ptp: ocp: Add firmware header checks
  ptp: ocp: fix PPS source selector debugfs reporting
  ptp: ocp: add .init function for sma_op vector
  ptp: ocp: vectorize the sma accessor functions
  ptp: ocp: constify selectors
  ptp: ocp: parameterize input/output sma selectors
  ptp: ocp: revise firmware display
  ptp: ocp: add Celestica timecard PCI ids
  ptp: ocp: Remove #ifdefs around PCI IDs
  ptp: ocp: 32-bit fixups for pci start address
  Revert "net/smc: fix listen processing for SMC-Rv2"
  ath6kl: Use cc-disable-warning to disable -Wdangling-pointer
  selftests/bpf: Dynptr tests
  bpf: Add dynptr data slices
  bpf: Add bpf_dynptr_read and bpf_dynptr_write
  bpf: Dynptr support for ring buffers
  bpf: Add bpf_dynptr_from_mem for local dynptrs
  bpf: Add verifier support for dynptrs
  bpf: Suppress 'passing zero to PTR_ERR' warning
  bpf: Introduce bpf_arch_text_invalidate for bpf_prog_pack
  ...
2022-05-25 12:22:58 -07:00
Kees Cook
b146cbf2e3 af_unix: Silence randstruct GCC plugin warning
While preparing for Clang randstruct support (which duplicated many of
the warnings the randstruct GCC plugin warned about), one strange one
remained only for the randstruct GCC plugin. Eliminating this rids
the plugin of the last exception.

It seems the plugin is happy to dereference individual members of
a cross-struct cast, but it is upset about casting to a whole object
pointer. This only manifests in one place in the kernel, so just replace
the variable with individual member accesses. There is no change in
executable instruction output.

Drop the last exception from the randstruct GCC plugin.

Cc: "David S. Miller" <davem@davemloft.net>
Cc: Christoph Hellwig <hch@infradead.org>
Cc: Paolo Abeni <pabeni@redhat.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Cong Wang <cong.wang@bytedance.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Cc: netdev@vger.kernel.org
Cc: linux-hardening@vger.kernel.org
Acked-by: Kuniyuki Iwashima <kuniyu@amazon.co.jp>
Link: https://lore.kernel.org/lkml/20220511022217.58586-1-kuniyu@amazon.co.jp
Acked-by: Jakub Kicinski <kuba@kernel.org>
Link: https://lore.kernel.org/lkml/20220511151542.4cb3ff17@kernel.org
Signed-off-by: Kees Cook <keescook@chromium.org>
2022-05-16 16:02:21 -07:00
Oliver Hartkopp
ec095263a9 net: remove noblock parameter from recvmsg() entities
The internal recvmsg() functions have two parameters 'flags' and 'noblock'
that were merged inside skb_recv_datagram(). As a follow up patch to commit
f4b41f062c42 ("net: remove noblock parameter from skb_recv_datagram()")
this patch removes the separate 'noblock' parameter for recvmsg().

Analogue to the referenced patch for skb_recv_datagram() the 'flags' and
'noblock' parameters are unnecessarily split up with e.g.

err = sk->sk_prot->recvmsg(sk, msg, size, flags & MSG_DONTWAIT,
                           flags & ~MSG_DONTWAIT, &addr_len);

or in

err = INDIRECT_CALL_2(sk->sk_prot->recvmsg, tcp_recvmsg, udp_recvmsg,
                      sk, msg, size, flags & MSG_DONTWAIT,
                      flags & ~MSG_DONTWAIT, &addr_len);

instead of simply using only flags all the time and check for MSG_DONTWAIT
where needed (to preserve for the formerly separated no(n)block condition).

Signed-off-by: Oliver Hartkopp <socketcan@hartkopp.net>
Link: https://lore.kernel.org/r/20220411124955.154876-1-socketcan@hartkopp.net
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2022-04-12 15:00:25 +02:00
Oliver Hartkopp
f4b41f062c net: remove noblock parameter from skb_recv_datagram()
skb_recv_datagram() has two parameters 'flags' and 'noblock' that are
merged inside skb_recv_datagram() by 'flags | (noblock ? MSG_DONTWAIT : 0)'

As 'flags' may contain MSG_DONTWAIT as value most callers split the 'flags'
into 'flags' and 'noblock' with finally obsolete bit operations like this:

skb_recv_datagram(sk, flags & ~MSG_DONTWAIT, flags & MSG_DONTWAIT, &rc);

And this is not even done consistently with the 'flags' parameter.

This patch removes the obsolete and costly splitting into two parameters
and only performs bit operations when really needed on the caller side.

One missing conversion thankfully reported by kernel test robot. I missed
to enable kunit tests to build the mctp code.

Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Oliver Hartkopp <socketcan@hartkopp.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
2022-04-06 13:45:26 +01:00
Jakub Kicinski
89695196f0 Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/net
Merge in overtime fixes, no conflicts.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-03-23 10:53:49 -07:00
Kuniyuki Iwashima
4edf21aa94 af_unix: Remove unnecessary brackets around CONFIG_AF_UNIX_OOB.
Let's remove unnecessary brackets around CONFIG_AF_UNIX_OOB.

Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.co.jp>
Link: https://lore.kernel.org/r/20220317032308.65372-1-kuniyu@amazon.co.jp
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-03-18 14:06:39 -07:00
Kuniyuki Iwashima
d9a232d435 af_unix: Support POLLPRI for OOB.
The commit 314001f0bf92 ("af_unix: Add OOB support") introduced OOB for
AF_UNIX, but it lacks some changes for POLLPRI.  Let's add the missing
piece.

In the selftest, normal datagrams are sent followed by OOB data, so this
commit replaces `POLLIN | POLLPRI` with just `POLLPRI` in the first test
case.

Fixes: 314001f0bf92 ("af_unix: Add OOB support")
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.co.jp>
Signed-off-by: David S. Miller <davem@davemloft.net>
2022-03-18 13:30:52 +00:00
Kuniyuki Iwashima
e82025c623 af_unix: Fix some data-races around unix_sk(sk)->oob_skb.
Out-of-band data automatically places a "mark" showing wherein the
sequence the out-of-band data would have been.  If the out-of-band data
implies cancelling everything sent so far, the "mark" is helpful to flush
them.  When the socket's read pointer reaches the "mark", the ioctl() below
sets a non zero value to the arg `atmark`:

The out-of-band data is queued in sk->sk_receive_queue as well as ordinary
data and also saved in unix_sk(sk)->oob_skb.  It can be used to test if the
head of the receive queue is the out-of-band data meaning the socket is at
the "mark".

While testing that, unix_ioctl() reads unix_sk(sk)->oob_skb locklessly.
Thus, all accesses to oob_skb need some basic protection to avoid
load/store tearing which KCSAN detects when these are called concurrently:

  - ioctl(fd_a, SIOCATMARK, &atmark, sizeof(atmark))
  - send(fd_b_connected_to_a, buf, sizeof(buf), MSG_OOB)

BUG: KCSAN: data-race in unix_ioctl / unix_stream_sendmsg

write to 0xffff888003d9cff0 of 8 bytes by task 175 on cpu 1:
 unix_stream_sendmsg (net/unix/af_unix.c:2087 net/unix/af_unix.c:2191)
 sock_sendmsg (net/socket.c:705 net/socket.c:725)
 __sys_sendto (net/socket.c:2040)
 __x64_sys_sendto (net/socket.c:2048)
 do_syscall_64 (arch/x86/entry/common.c:50 arch/x86/entry/common.c:80)
 entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:113)

read to 0xffff888003d9cff0 of 8 bytes by task 176 on cpu 0:
 unix_ioctl (net/unix/af_unix.c:3101 (discriminator 1))
 sock_do_ioctl (net/socket.c:1128)
 sock_ioctl (net/socket.c:1242)
 __x64_sys_ioctl (fs/ioctl.c:52 fs/ioctl.c:874 fs/ioctl.c:860 fs/ioctl.c:860)
 do_syscall_64 (arch/x86/entry/common.c:50 arch/x86/entry/common.c:80)
 entry_SYSCALL_64_after_hwframe (arch/x86/entry/entry_64.S:113)

value changed: 0xffff888003da0c00 -> 0xffff888003da0d00

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 176 Comm: unix_race_oob_i Not tainted 5.17.0-rc5-59529-g83dc4c2af682 #12
Hardware name: Red Hat KVM, BIOS 1.11.0-2.amzn2 04/01/2014

Fixes: 314001f0bf92 ("af_unix: Add OOB support")
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.co.jp>
Signed-off-by: David S. Miller <davem@davemloft.net>
2022-03-18 13:30:52 +00:00
Kuniyuki Iwashima
eb7d8f1d9e bpf: Support bpf_(get|set)sockopt() in bpf unix iter.
This patch makes bpf_(get|set)sockopt() available when iterating AF_UNIX
sockets.

Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.co.jp>
Link: https://lore.kernel.org/r/20220113002849.4384-4-kuniyu@amazon.co.jp
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-01-18 15:45:06 -08:00
Kuniyuki Iwashima
855d8e77ff bpf: af_unix: Use batching algorithm in bpf unix iter.
The commit 04c7820b776f ("bpf: tcp: Bpf iter batching and lock_sock")
introduces the batching algorithm to iterate TCP sockets with more
consistency.

This patch uses the same algorithm to iterate AF_UNIX sockets.

Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.co.jp>
Link: https://lore.kernel.org/r/20220113002849.4384-3-kuniyu@amazon.co.jp
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-01-18 15:45:06 -08:00
Kuniyuki Iwashima
4408d55a64 af_unix: Refactor unix_next_socket().
Currently, unix_next_socket() is overloaded depending on the 2nd argument.
If it is NULL, unix_next_socket() returns the first socket in the hash.  If
not NULL, it returns the next socket in the same hash list or the first
socket in the next non-empty hash list.

This patch refactors unix_next_socket() into two functions unix_get_first()
and unix_get_next().  unix_get_first() newly acquires a lock and returns
the first socket in the list.  unix_get_next() returns the next socket in a
list or releases a lock and falls back to unix_get_first().

In the following patch, bpf iter holds entire sockets in a list and always
releases the lock before .show().  It always calls unix_get_first() to
acquire a lock in each iteration.  So, this patch makes the change easier
to follow.

Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.co.jp>
Link: https://lore.kernel.org/r/20220113002849.4384-2-kuniyu@amazon.co.jp
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
2022-01-18 15:45:06 -08:00
Jakub Kicinski
b6459415b3 net: Don't include filter.h from net/sock.h
sock.h is pretty heavily used (5k objects rebuilt on x86 after
it's touched). We can drop the include of filter.h from it and
add a forward declaration of struct sk_filter instead.
This decreases the number of rebuilt objects when bpf.h
is touched from ~5k to ~1k.

There's a lot of missing includes this was masking. Primarily
in networking tho, this time.

Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Marc Kleine-Budde <mkl@pengutronix.de>
Acked-by: Florian Fainelli <f.fainelli@gmail.com>
Acked-by: Nikolay Aleksandrov <nikolay@nvidia.com>
Acked-by: Stefano Garzarella <sgarzare@redhat.com>
Link: https://lore.kernel.org/bpf/20211229004913.513372-1-kuba@kernel.org
2021-12-29 08:48:14 -08:00
Kuniyuki Iwashima
9acbc584c3 af_unix: Relax race in unix_autobind().
When we bind an AF_UNIX socket without a name specified, the kernel selects
an available one from 0x00000 to 0xFFFFF.  unix_autobind() starts searching
from a number in the 'static' variable and increments it after acquiring
two locks.

If multiple processes try autobind, they obtain the same lock and check if
a socket in the hash list has the same name.  If not, one process uses it,
and all except one end up retrying the _next_ number (actually not, it may
be incremented by the other processes).  The more we autobind sockets in
parallel, the longer the latency gets.  We can avoid such a race by
searching for a name from a random number.

These show latency in unix_autobind() while 64 CPUs are simultaneously
autobind-ing 1024 sockets for each.

  Without this patch:

     usec          : count     distribution
        0          : 1176     |***                                     |
        2          : 3655     |***********                             |
        4          : 4094     |*************                           |
        6          : 3831     |************                            |
        8          : 3829     |************                            |
        10         : 3844     |************                            |
        12         : 3638     |***********                             |
        14         : 2992     |*********                               |
        16         : 2485     |*******                                 |
        18         : 2230     |*******                                 |
        20         : 2095     |******                                  |
        22         : 1853     |*****                                   |
        24         : 1827     |*****                                   |
        26         : 1677     |*****                                   |
        28         : 1473     |****                                    |
        30         : 1573     |*****                                   |
        32         : 1417     |****                                    |
        34         : 1385     |****                                    |
        36         : 1345     |****                                    |
        38         : 1344     |****                                    |
        40         : 1200     |***                                     |

  With this patch:

     usec          : count     distribution
        0          : 1855     |******                                  |
        2          : 6464     |*********************                   |
        4          : 9936     |********************************        |
        6          : 12107    |****************************************|
        8          : 10441    |**********************************      |
        10         : 7264     |***********************                 |
        12         : 4254     |**************                          |
        14         : 2538     |********                                |
        16         : 1596     |*****                                   |
        18         : 1088     |***                                     |
        20         : 800      |**                                      |
        22         : 670      |**                                      |
        24         : 601      |*                                       |
        26         : 562      |*                                       |
        28         : 525      |*                                       |
        30         : 446      |*                                       |
        32         : 378      |*                                       |
        34         : 337      |*                                       |
        36         : 317      |*                                       |
        38         : 314      |*                                       |
        40         : 298      |                                        |

Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.co.jp>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-11-26 18:01:58 -08:00
Kuniyuki Iwashima
afd20b9290 af_unix: Replace the big lock with small locks.
The hash table of AF_UNIX sockets is protected by the single lock.  This
patch replaces it with per-hash locks.

The effect is noticeable when we handle multiple sockets simultaneously.
Here is a test result on an EC2 c5.24xlarge instance.  It shows latency
(under 10us only) in unix_insert_unbound_socket() while 64 CPUs creating
1024 sockets for each in parallel.

  Without this patch:

     nsec          : count     distribution
        0          : 179      |                                        |
        500        : 3021     |*********                               |
        1000       : 6271     |*******************                     |
        1500       : 6318     |*******************                     |
        2000       : 5828     |*****************                       |
        2500       : 5124     |***************                         |
        3000       : 4426     |*************                           |
        3500       : 3672     |***********                             |
        4000       : 3138     |*********                               |
        4500       : 2811     |********                                |
        5000       : 2384     |*******                                 |
        5500       : 2023     |******                                  |
        6000       : 1954     |*****                                   |
        6500       : 1737     |*****                                   |
        7000       : 1749     |*****                                   |
        7500       : 1520     |****                                    |
        8000       : 1469     |****                                    |
        8500       : 1394     |****                                    |
        9000       : 1232     |***                                     |
        9500       : 1138     |***                                     |
        10000      : 994      |***                                     |

  With this patch:

     nsec          : count     distribution
        0          : 1634     |****                                    |
        500        : 13170    |****************************************|
        1000       : 13156    |*************************************** |
        1500       : 9010     |***************************             |
        2000       : 6363     |*******************                     |
        2500       : 4443     |*************                           |
        3000       : 3240     |*********                               |
        3500       : 2549     |*******                                 |
        4000       : 1872     |*****                                   |
        4500       : 1504     |****                                    |
        5000       : 1247     |***                                     |
        5500       : 1035     |***                                     |
        6000       : 889      |**                                      |
        6500       : 744      |**                                      |
        7000       : 634      |*                                       |
        7500       : 498      |*                                       |
        8000       : 433      |*                                       |
        8500       : 355      |*                                       |
        9000       : 336      |*                                       |
        9500       : 284      |                                        |
        10000      : 243      |                                        |

Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.co.jp>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-11-26 18:01:58 -08:00
Kuniyuki Iwashima
e6b4b87389 af_unix: Save hash in sk_hash.
To replace unix_table_lock with per-hash locks in the next patch, we need
to save a hash in each socket because /proc/net/unix or BPF prog iterate
sockets while holding a hash table lock and release it later in a different
function.

Currently, we store a real/pseudo hash in struct unix_address.  However, we
do not allocate it to unbound sockets, nor should we do just for that.  For
this purpose, we can use sk_hash.  Then, we no longer use the hash field in
struct unix_address and can remove it.

Also, this patch does
  - rename unix_insert_socket() to unix_insert_unbound_socket()
  - remove the redundant list argument from __unix_insert_socket() and
     unix_insert_unbound_socket()
  - use 'unsigned int' instead of 'unsigned' in __unix_set_addr_hash()
  - remove 'inline' from unix_remove_socket() and
     unix_insert_unbound_socket().

Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.co.jp>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-11-26 18:01:57 -08:00
Kuniyuki Iwashima
f452be496a af_unix: Add helpers to calculate hashes.
This patch adds three helper functions that calculate hashes for unbound
sockets and bound sockets with BSD/abstract addresses.

Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.co.jp>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-11-26 18:01:57 -08:00
Kuniyuki Iwashima
5ce7ab4961 af_unix: Remove UNIX_ABSTRACT() macro and test sun_path[0] instead.
In BSD and abstract address cases, we store sockets in the hash table with
keys between 0 and UNIX_HASH_SIZE - 1.  However, the hash saved in a socket
varies depending on its address type; sockets with BSD addresses always
have UNIX_HASH_SIZE in their unix_sk(sk)->addr->hash.

This is just for the UNIX_ABSTRACT() macro used to check the address type.
The difference of the saved hashes comes from the first byte of the address
in the first place.  So, we can test it directly.

Then we can keep a real hash in each socket and replace unix_table_lock
with per-hash locks in the later patch.

Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.co.jp>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-11-26 18:01:56 -08:00
Kuniyuki Iwashima
12f21c49ad af_unix: Allocate unix_address in unix_bind_(bsd|abstract)().
To terminate address with '\0' in unix_bind_bsd(), we add
unix_create_addr() and call it in unix_bind_bsd() and unix_bind_abstract().

Also, unix_bind_abstract() does not return -EEXIST.  Only
kern_path_create() and vfs_mknod() in unix_bind_bsd() can return it,
so we move the last error check in unix_bind() to unix_bind_bsd().

Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.co.jp>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-11-26 18:01:56 -08:00
Kuniyuki Iwashima
5c32a3ed64 af_unix: Remove unix_mkname().
This patch removes unix_mkname() and postpones calculating a hash to
unix_bind_abstract().  Some BSD stuffs still remain in unix_bind()
though, the next patch packs them into unix_bind_bsd().

Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.co.jp>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-11-26 18:01:55 -08:00
Kuniyuki Iwashima
d2d8c9fddb af_unix: Copy unix_mkname() into unix_find_(bsd|abstract)().
We should not call unix_mkname() before unix_find_other() and instead do
the same thing where necessary based on the address type:

  - terminating the address with '\0' in unix_find_bsd()
  - calculating the hash in unix_find_abstract().

Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.co.jp>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-11-26 18:01:55 -08:00