Dear Linux kernel maintainers, Syzkaller reports this previously unknown bug on Linux 6.8.0-rc3-00043-ga69d20885494-dirty #4. Seems like the bug was silently or unintendedly fixed in the latest version. ``` ------------[ cut here ]------------ do not call blocking ops when !TASK_RUNNING; state=1 set at [<ffffffff815d2494>] prepare_to_wait+0xa4/0x380 kernel/sched/wait.c:237 WARNING: CPU: 2 PID: 397056 at kernel/sched/core.c:10099 __might_sleep+0x114/0x160 kernel/sched/core.c:10099 Modules linked in: CPU: 2 PID: 397056 Comm: syz-executor.2 Not tainted 6.8.0-rc3-00043-ga69d20885494-dirty #50 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.15.0-1 04/01/2014 RIP: 0010:__might_sleep+0x114/0x160 kernel/sched/core.c:10099 Code: 03 00 48 8d bb 50 17 00 00 48 89 fa 48 c1 ea 03 80 3c 02 00 75 37 48 8b 93 50 17 00 00 48 c7 c7 a0 55 0b 8a e8 9d d4 f4 ff 90 <0f> 0b 90 90 e9 71 ff ff ff e8 4e 28 78 00 e9 22 ff ff ff 89 34 24 RSP: 0018:ffffc9000bf5fb40 EFLAGS: 00010282 RAX: 0000000000000000 RBX: ffff888053524880 RCX: 0000000000000000 RDX: 0000000000000002 RSI: 0000000000000004 RDI: 0000000000000001 RBP: ffffffff8a0bc600 R08: 0000000000000001 R09: ffffed1017315171 R10: ffff8880b98a8b8b R11: 0000000000000000 R12: 0000000000000249 R13: 0000000000000000 R14: dffffc0000000000 R15: ffffc9000bf5fd20 FS: 00007fe4ffdcc640(0000) GS:ffff8880b9880000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fa501ba3098 CR3: 0000000022b8c000 CR4: 0000000000750ef0 PKRU: 55555554 Call Trace: <TASK> __mutex_lock_common kernel/locking/mutex.c:585 [inline] __mutex_lock+0xb4/0x940 kernel/locking/mutex.c:752 io_rsrc_ref_quiesce+0x590/0x940 io_uring/rsrc.c:253 io_sqe_buffers_unregister+0xa2/0x340 io_uring/rsrc.c:799 __io_uring_register io_uring/register.c:424 [inline] __do_sys_io_uring_register+0x5b9/0x2400 io_uring/register.c:613 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xd8/0x270 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x6f/0x77 RIP: 0033:0x7fe4ff0902ed Code: c3 e8 97 2b 00 00 0f 1f 80 00 00 00 00 f3 0f 1e fa 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b0 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007fe4ffdcc028 EFLAGS: 00000246 ORIG_RAX: 00000000000001ab RAX: ffffffffffffffda RBX: 00007fe4ff1cbf80 RCX: 00007fe4ff0902ed RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000003 RBP: 00007fe4ff0f150e R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 000000000000000b R14: 00007fe4ff1cbf80 R15: 00007fe4ffdac000 </TASK> ``` crepro is in the attachment. Best Regards Xdchase
Attachment:
repro.c
Description: Binary data
