syzbot


KCSAN: data-race in __io_free_req_finish / __io_uring_files_cancel

Status: auto-closed as invalid on 2020/11/19 23:33
Subsystems: fs
[Documentation on labels]
First crash: 1293d, last: 1293d

Sample crash report:
BUG: KCSAN: data-race in __io_free_req_finish / __io_uring_files_cancel

write to 0xffff8880752c3340 of 1 bytes by task 25276 on cpu 1:
 __io_uring_files_cancel+0x4c/0x190 fs/io_uring.c:8594
 io_uring_files_cancel include/linux/io_uring.h:35 [inline]
 exit_files+0x6a/0xc0 fs/file.c:456
 do_exit+0x696/0x1660 kernel/exit.c:801
 do_group_exit+0xcb/0x180 kernel/exit.c:903
 get_signal+0xe6f/0x15f0 kernel/signal.c:2757
 arch_do_signal+0x25/0x270 arch/x86/kernel/signal.c:811
 exit_to_user_mode_loop kernel/entry/common.c:161 [inline]
 exit_to_user_mode_prepare+0x124/0x210 kernel/entry/common.c:192
 syscall_exit_to_user_mode+0x16/0x30 kernel/entry/common.c:267
 do_syscall_64+0x45/0x80 arch/x86/entry/common.c:56
 entry_SYSCALL_64_after_hwframe+0x44/0xa9

read to 0xffff8880752c3340 of 1 bytes by task 25279 on cpu 0:
 __io_free_req_finish+0x57/0x1f0 fs/io_uring.c:1720
 __io_free_req fs/io_uring.c:1749 [inline]
 io_free_req+0x7b/0xc0 fs/io_uring.c:2004
 io_put_req fs/io_uring.c:2085 [inline]
 io_free_work+0x3c/0x80 fs/io_uring.c:7553
 io_worker_handle_work+0xb58/0xd80 fs/io-wq.c:556
 io_wqe_worker+0x212/0x830 fs/io-wq.c:590
 kthread+0x20d/0x230 kernel/kthread.c:292
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:296

Reported by Kernel Concurrency Sanitizer on:
CPU: 0 PID: 25279 Comm: io_wqe_worker-0 Not tainted 5.9.0-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
==================================================================

Crashes (1):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2020/10/15 23:28 upstream 726eb70e0d34 6e262c73 .config console log report info ci2-upstream-kcsan-gce
* Struck through repros no longer work on HEAD.