syzbot


KCSAN: data-race in pipe_release / pipe_wait_writable

Status: auto-closed as invalid on 2022/02/23 01:29
Reported-by: syzbot+@syzkaller.appspotmail.com
First crash: 318d, last: 318d

Sample crash report:
==================================================================
BUG: KCSAN: data-race in pipe_release / pipe_wait_writable

write to 0xffff888135d5936c of 4 bytes by task 5357 on cpu 1:
 put_pipe_info fs/pipe.c:702 [inline]
 pipe_release+0x186/0x1e0 fs/pipe.c:732
 __fput+0x295/0x520 fs/file_table.c:280
 ____fput+0x11/0x20 fs/file_table.c:313
 task_work_run+0x8e/0x110 kernel/task_work.c:164
 tracehook_notify_resume include/linux/tracehook.h:188 [inline]
 exit_to_user_mode_loop kernel/entry/common.c:175 [inline]
 exit_to_user_mode_prepare+0x160/0x190 kernel/entry/common.c:207
 __syscall_exit_to_user_mode_work kernel/entry/common.c:289 [inline]
 syscall_exit_to_user_mode+0x20/0x40 kernel/entry/common.c:300
 do_syscall_64+0x50/0xd0 arch/x86/entry/common.c:86
 entry_SYSCALL_64_after_hwframe+0x44/0xae

read to 0xffff888135d5936c of 4 bytes by task 5363 on cpu 0:
 pipe_lock_nested fs/pipe.c:80 [inline]
 pipe_lock fs/pipe.c:89 [inline]
 pipe_wait_writable+0x1f5/0x240 fs/pipe.c:1052
 opipe_prep+0x160/0x200 fs/splice.c:1427
 splice_pipe_to_pipe fs/splice.c:1454 [inline]
 do_splice+0x30e/0xde0 fs/splice.c:1054
 __do_splice fs/splice.c:1144 [inline]
 __do_sys_splice fs/splice.c:1350 [inline]
 __se_sys_splice+0x2bd/0x3a0 fs/splice.c:1332
 __x64_sys_splice+0x74/0x80 fs/splice.c:1332
 do_syscall_x64 arch/x86/entry/common.c:50 [inline]
 do_syscall_64+0x44/0xd0 arch/x86/entry/common.c:80
 entry_SYSCALL_64_after_hwframe+0x44/0xae

value changed: 0x00000002 -> 0x00000001

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 5363 Comm: syz-executor.0 Not tainted 5.16.0-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
==================================================================

Crashes (1):
Manager Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Title
ci2-upstream-kcsan-gce 2022/01/19 01:27 upstream 99613159ad74 731a2d23 .config log report info KCSAN: data-race in pipe_release / pipe_wait_writable
* Struck through repros no longer work on HEAD.