On Mon, Sep 06 2021 at 03:28, syzbot wrote: > syzbot found the following issue on: > > HEAD commit: 835d31d319d9 Merge tag 'media/v5.15-1' of git://git.kernel.. > git tree: upstream > console output: https://syzkaller.appspot.com/x/log.txt?x=14489886300000 > kernel config: https://syzkaller.appspot.com/x/.config?x=d793523866f2daea > dashboard link: https://syzkaller.appspot.com/bug?extid=b935db3fe409625cca1b > compiler: Debian clang version 11.0.1-2, GNU ld (GNU Binutils for Debian) 2.35.1 > > Unfortunately, I don't have any reproducer for this issue yet. > > IMPORTANT: if you fix the issue, please add the following tag to the commit: > Reported-by: syzbot+b935db3fe409625cca1b@xxxxxxxxxxxxxxxxxxxxxxxxx > > general protection fault, probably for non-canonical address 0xdffffc0000000000: 0000 [#1] PREEMPT SMP KASAN > KASAN: null-ptr-deref in range [0x0000000000000000-0x0000000000000007] > CPU: 0 PID: 12936 Comm: iou-sqp-12929 Not tainted 5.14.0-syzkaller #0 > Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 > RIP: 0010:lock_hrtimer_base kernel/time/hrtimer.c:173 [inline] That's almost certainly deferencing hrtimer->base and as that is NULL this looks like a not initialized hrtimer. Jens? > RIP: 0010:hrtimer_start_range_ns+0xc9/0x1ae0 kernel/time/hrtimer.c:1296 > Code: 89 9c 24 88 00 00 00 42 80 3c 33 00 74 08 48 89 ef e8 7b 34 5b 00 4c 8b 6d 00 4d 39 fd 0f 84 95 00 00 00 4d 89 ef 49 c1 ef 03 <43> 80 3c 37 00 74 08 4c 89 ef e8 58 34 5b 00 49 8b 7d 00 e8 6f 19 > RSP: 0018:ffffc900097af170 EFLAGS: 00010046 > RAX: ffff888016d49508 RBX: 1ffff11002da92a7 RCX: ffff888027371c80 > RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000001 > RBP: ffff888016d49538 R08: ffffffff816fb4b5 R09: 0000000000000003 > R10: fffff520012f5e2d R11: 0000000000000004 R12: 0000000000000000 > R13: 0000000000000000 R14: dffffc0000000000 R15: 0000000000000000 > FS: 00007f7386f28700(0000) GS:ffff8880b9c00000(0000) knlGS:0000000000000000 > CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 > CR2: 0000000000000000 CR3: 000000002b5e4000 CR4: 00000000001526f0 > DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 > DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 > Call Trace: > hrtimer_start include/linux/hrtimer.h:418 [inline] > io_timeout fs/io_uring.c:6120 [inline] > io_issue_sqe+0x53d3/0x9280 fs/io_uring.c:6590 > __io_queue_sqe+0xe3/0x1000 fs/io_uring.c:6864 > tctx_task_work+0x2ad/0x560 fs/io_uring.c:2143 > task_work_run+0x146/0x1c0 kernel/task_work.c:164 > tracehook_notify_signal include/linux/tracehook.h:212 [inline] > io_run_task_work+0x110/0x140 fs/io_uring.c:2403 > io_sq_thread+0xb5e/0x1220 fs/io_uring.c:7337 > ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 > Modules linked in: > ---[ end trace 841fafb7511d53d3 ]--- > RIP: 0010:lock_hrtimer_base kernel/time/hrtimer.c:173 [inline] > RIP: 0010:hrtimer_start_range_ns+0xc9/0x1ae0 kernel/time/hrtimer.c:1296 > Code: 89 9c 24 88 00 00 00 42 80 3c 33 00 74 08 48 89 ef e8 7b 34 5b 00 4c 8b 6d 00 4d 39 fd 0f 84 95 00 00 00 4d 89 ef 49 c1 ef 03 <43> 80 3c 37 00 74 08 4c 89 ef e8 58 34 5b 00 49 8b 7d 00 e8 6f 19 > RSP: 0018:ffffc900097af170 EFLAGS: 00010046 > RAX: ffff888016d49508 RBX: 1ffff11002da92a7 RCX: ffff888027371c80 > RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000001 > RBP: ffff888016d49538 R08: ffffffff816fb4b5 R09: 0000000000000003 > R10: fffff520012f5e2d R11: 0000000000000004 R12: 0000000000000000 > R13: 0000000000000000 R14: dffffc0000000000 R15: 0000000000000000 > FS: 00007f7386f28700(0000) GS:ffff8880b9c00000(0000) knlGS:0000000000000000 > CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 > CR2: 0000000000000000 CR3: 000000002b5e4000 CR4: 00000000001526f0 > DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 > DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 > ---------------- > Code disassembly (best guess): > 0: 89 9c 24 88 00 00 00 mov %ebx,0x88(%rsp) > 7: 42 80 3c 33 00 cmpb $0x0,(%rbx,%r14,1) > c: 74 08 je 0x16 > e: 48 89 ef mov %rbp,%rdi > 11: e8 7b 34 5b 00 callq 0x5b3491 > 16: 4c 8b 6d 00 mov 0x0(%rbp),%r13 > 1a: 4d 39 fd cmp %r15,%r13 > 1d: 0f 84 95 00 00 00 je 0xb8 > 23: 4d 89 ef mov %r13,%r15 > 26: 49 c1 ef 03 shr $0x3,%r15 > * 2a: 43 80 3c 37 00 cmpb $0x0,(%r15,%r14,1) <-- trapping instruction > 2f: 74 08 je 0x39 > 31: 4c 89 ef mov %r13,%rdi > 34: e8 58 34 5b 00 callq 0x5b3491 > 39: 49 8b 7d 00 mov 0x0(%r13),%rdi > 3d: e8 .byte 0xe8 > 3e: 6f outsl %ds:(%rsi),(%dx) > 3f: 19 .byte 0x19 > > > --- > This report is generated by a bot. It may contain errors. > See https://goo.gl/tpsmEJ for more information about syzbot. > syzbot engineers can be reached at syzkaller@xxxxxxxxxxxxxxxx. > > syzbot will keep track of this issue. See: > https://goo.gl/tpsmEJ#status for how to communicate with syzbot.
