syzbot


KCSAN: data-race in io_cqring_overflow_flush / io_submit_sqes

Status: auto-closed as invalid on 2020/12/21 11:48
Subsystems: fs
[Documentation on labels]
Reported-by: syzbot+6678a9927846108ce058@syzkaller.appspotmail.com
First crash: 1283d, last: 1270d

Sample crash report:
==================================================================
BUG: KCSAN: data-race in io_cqring_overflow_flush / io_submit_sqes

read-write to 0xffff88810a5adc44 of 1 bytes by task 14372 on cpu 1:
 io_cqring_overflow_flush+0x95/0x720 fs/io_uring.c:1614
 io_uring_cancel_task_requests fs/io_uring.c:8604 [inline]
 __io_uring_files_cancel+0x17e/0x1310 fs/io_uring.c:8683
 io_uring_files_cancel include/linux/io_uring.h:50 [inline]
 exit_files+0x6a/0xc0 fs/file.c:456
 do_exit+0x422/0x15a0 kernel/exit.c:801
 do_group_exit+0xc8/0x170 kernel/exit.c:903
 get_signal+0xf9b/0x1510 kernel/signal.c:2757
 arch_do_signal+0x25/0x260 arch/x86/kernel/signal.c:811
 exit_to_user_mode_loop kernel/entry/common.c:161 [inline]
 exit_to_user_mode_prepare+0xde/0x170 kernel/entry/common.c:191
 syscall_exit_to_user_mode+0x16/0x30 kernel/entry/common.c:266
 do_syscall_64+0x45/0x80 arch/x86/entry/common.c:56
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

read to 0xffff88810a5adc44 of 1 bytes by task 14412 on cpu 0:
 io_check_restriction fs/io_uring.c:6412 [inline]
 io_init_req fs/io_uring.c:6462 [inline]
 io_submit_sqes+0x6a3/0x1300 fs/io_uring.c:6539
 __do_sys_io_uring_enter fs/io_uring.c:8870 [inline]
 __se_sys_io_uring_enter+0x4c1/0xa60 fs/io_uring.c:8819
 __x64_sys_io_uring_enter+0x74/0x80 fs/io_uring.c:8819
 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: 0 PID: 14412 Comm: syz-executor.5 Not tainted 5.10.0-rc2-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
==================================================================

Crashes (3):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2020/11/02 10:17 upstream 3cea11cd5e3b 8bc4594f .config console log report info ci2-upstream-kcsan-gce
2020/10/22 05:33 upstream f804b3159482 be6b1582 .config console log report info ci2-upstream-kcsan-gce
2020/10/20 22:45 upstream 270315b8235e ff4a3345 .config console log report info ci2-upstream-kcsan-gce
* Struck through repros no longer work on HEAD.