KCSAN: data-race in smc_poll / smc_switch_to

Kernel	Title	Rank 🛈	Repro	Cause bisect	Fix bisect	Count	Last	Reported	Patched	Status
upstream	KCSAN: data-race in smc_poll / smc_switch_to_fallback smc	6				1	1004d	942d	0/29	auto-obsoleted due to no activity on 2023/03/26 15:22

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BUG: KCSAN: data-race in smc_poll / smc_switch_to_fallback

write to 0xffff888104708c3d of 1 bytes by task 14298 on cpu 0:
 smc_switch_to_fallback+0x5a/0x800 net/smc/af_smc.c:914
 smc_sendmsg+0xce/0x2f0 net/smc/af_smc.c:2786
 sock_sendmsg_nosec net/socket.c:712 [inline]
 __sock_sendmsg+0x145/0x180 net/socket.c:727
 __sys_sendto+0x268/0x330 net/socket.c:2180
 __do_sys_sendto net/socket.c:2187 [inline]
 __se_sys_sendto net/socket.c:2183 [inline]
 __x64_sys_sendto+0x76/0x90 net/socket.c:2183
 x64_sys_call+0x2eb6/0x2fb0 arch/x86/include/generated/asm/syscalls_64.h:45
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xd2/0x200 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

read to 0xffff888104708c3d of 1 bytes by task 14295 on cpu 1:
 smc_poll+0x4a/0x530 net/smc/af_smc.c:2872
 sock_poll+0x218/0x240 net/socket.c:1379
 vfs_poll include/linux/poll.h:82 [inline]
 __io_arm_poll_handler+0x1eb/0xb70 io_uring/poll.c:583
 io_poll_add+0x69/0xe0 io_uring/poll.c:893
 __io_issue_sqe+0xfe/0x2e0 io_uring/io_uring.c:1738
 io_issue_sqe+0x53/0x970 io_uring/io_uring.c:1761
 io_queue_sqe io_uring/io_uring.c:1968 [inline]
 io_submit_sqe io_uring/io_uring.c:2224 [inline]
 io_submit_sqes+0x667/0xfd0 io_uring/io_uring.c:2337
 __do_sys_io_uring_enter io_uring/io_uring.c:3404 [inline]
 __se_sys_io_uring_enter+0x1c1/0x1b70 io_uring/io_uring.c:3338
 __x64_sys_io_uring_enter+0x78/0x90 io_uring/io_uring.c:3338
 x64_sys_call+0x28c8/0x2fb0 arch/x86/include/generated/asm/syscalls_64.h:427
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xd2/0x200 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

value changed: 0x00 -> 0x01

Reported by Kernel Concurrency Sanitizer on:
CPU: 1 UID: 0 PID: 14295 Comm: syz.3.4381 Not tainted 6.16.0-rc6-syzkaller-00037-ge2291551827f #0 PREEMPT(voluntary) 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/07/2025
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