KCSAN: data-race in af_alg_sendmsg / af_alg_wait_for_data (4)

[syzbot]

Hello,

syzbot found the following issue on:

HEAD commit: 34816d20 Merge tag 'gfs2-v5.10-rc5-fixes' of git://git.ker..
git tree: upstream
console output: https://syzkaller.appspot.com/x/log.txt?x=133a2dab500000
kernel config: https://syzkaller.appspot.com/x/.config?x=c949fed53798f819
dashboard link: https://syzkaller.appspot.com/bug?extid=0843a6d7ab43b4fd4ad4
compiler: clang version 12.0.0 (https://github.com/llvm/llvm-project.git 913f6005669cfb590c99865a90bc51ed0983d09d)
CC: [da...@davemloft.net her...@gondor.apana.org.au linux-...@vger.kernel.org linux-...@vger.kernel.org]

Unfortunately, I don't have any reproducer for this issue yet.

IMPORTANT: if you fix the issue, please add the following tag to the commit:
Reported-by: syzbot+0843a6...@syzkaller.appspotmail.com

==================================================================
BUG: KCSAN: data-race in af_alg_sendmsg / af_alg_wait_for_data

write to 0xffff88813b9c70d7 of 1 bytes by task 19559 on cpu 0:
af_alg_sendmsg+0x336/0xcb0 crypto/af_alg.c:871
skcipher_sendmsg+0x71/0x80 crypto/algif_skcipher.c:47
sock_sendmsg_nosec net/socket.c:651 [inline]
sock_sendmsg net/socket.c:671 [inline]
____sys_sendmsg+0x352/0x4c0 net/socket.c:2353
___sys_sendmsg net/socket.c:2407 [inline]
__sys_sendmsg+0x1e2/0x260 net/socket.c:2440
__do_sys_sendmsg net/socket.c:2449 [inline]
__se_sys_sendmsg net/socket.c:2447 [inline]
__x64_sys_sendmsg+0x42/0x50 net/socket.c:2447
do_syscall_64+0x39/0x80 arch/x86/entry/common.c:46
entry_SYSCALL_64_after_hwframe+0x44/0xa9

read to 0xffff88813b9c70d7 of 1 bytes by task 19548 on cpu 1:
af_alg_wait_for_data+0x160/0x360 crypto/af_alg.c:770
_skcipher_recvmsg crypto/algif_skcipher.c:65 [inline]
skcipher_recvmsg+0x17a/0x7f0 crypto/algif_skcipher.c:157
sock_recvmsg_nosec net/socket.c:885 [inline]
sock_recvmsg net/socket.c:903 [inline]
__sys_recvfrom+0x1cb/0x290 net/socket.c:2049
__do_sys_recvfrom net/socket.c:2067 [inline]
__se_sys_recvfrom net/socket.c:2063 [inline]
__x64_sys_recvfrom+0x74/0x90 net/socket.c:2063
do_syscall_64+0x39/0x80 arch/x86/entry/common.c:46
entry_SYSCALL_64_after_hwframe+0x44/0xa9

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 PID: 19548 Comm: syz-executor.0 Not tainted 5.10.0-rc6-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
==================================================================


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[syzbot]

Auto-closing this bug as obsolete.
Crashes did not happen for a while, no reproducer and no activity.