Hello, syzbot found the following issue on: HEAD commit: a9c9a6f741cd Merge tag 'scsi-misc' of git://git.kernel.org.. git tree: upstream console output: https://syzkaller.appspot.com/x/log.txt?x=14e6c8cd300000 kernel config: https://syzkaller.appspot.com/x/.config?x=c84ed2c3f57ace dashboard link: https://syzkaller.appspot.com/bug?extid=ba74b85fa15fd7a96437 compiler: Debian clang version 11.0.1-2, GNU ld (GNU Binutils for Debian) 2.35.1 syz repro: https://syzkaller.appspot.com/x/repro.syz?x=137a45a3300000 C reproducer: https://syzkaller.appspot.com/x/repro.c?x=105ba169300000 IMPORTANT: if you fix the issue, please add the following tag to the commit: Reported-by: syzbot+ba74b85fa15fd7a96437@xxxxxxxxxxxxxxxxxxxxxxxxx general protection fault, probably for non-canonical address 0xdffffc0000000005: 0000 [#1] PREEMPT SMP KASAN KASAN: null-ptr-deref in range [0x0000000000000028-0x000000000000002f] CPU: 1 PID: 8812 Comm: iou-sqp-8804 Not tainted 5.14.0-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 RIP: 0010:vfs_poll include/linux/poll.h:88 [inline] RIP: 0010:__io_arm_poll_handler+0x2fa/0xb10 fs/io_uring.c:5476 Code: 24 38 42 80 3c 20 00 74 08 48 89 ef e8 df 15 db ff 48 8b 6d 00 48 8d 5d 28 48 89 d8 48 c1 e8 03 48 b9 00 00 00 00 00 fc ff df <80> 3c 08 00 74 08 48 89 df e8 b8 15 db ff 4c 8b 23 49 83 c4 48 4c RSP: 0018:ffffc90001e7f0a8 EFLAGS: 00010206 RAX: 0000000000000005 RBX: 0000000000000028 RCX: dffffc0000000000 RDX: 0000000000000010 RSI: 0000000000000000 RDI: ffffc90001e7f1f0 RBP: 0000000000000000 R08: dffffc0000000000 R09: ffff88801252e820 R10: ffffed10024a5d06 R11: 0000000000000000 R12: dffffc0000000000 R13: 1ffff920003cfe3f R14: ffffc90001e7f1fc R15: ffffc90001e7f1f8 FS: 00007f6951c24700(0000) GS:ffff8880b9d00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000000000049a01d CR3: 000000002b182000 CR4: 00000000001506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: io_poll_add+0xf1/0x590 fs/io_uring.c:5751 io_issue_sqe+0x192b/0x9280 fs/io_uring.c:6569 __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 65dffd9e454d7c44 ]--- RIP: 0010:vfs_poll include/linux/poll.h:88 [inline] RIP: 0010:__io_arm_poll_handler+0x2fa/0xb10 fs/io_uring.c:5476 Code: 24 38 42 80 3c 20 00 74 08 48 89 ef e8 df 15 db ff 48 8b 6d 00 48 8d 5d 28 48 89 d8 48 c1 e8 03 48 b9 00 00 00 00 00 fc ff df <80> 3c 08 00 74 08 48 89 df e8 b8 15 db ff 4c 8b 23 49 83 c4 48 4c RSP: 0018:ffffc90001e7f0a8 EFLAGS: 00010206 RAX: 0000000000000005 RBX: 0000000000000028 RCX: dffffc0000000000 RDX: 0000000000000010 RSI: 0000000000000000 RDI: ffffc90001e7f1f0 RBP: 0000000000000000 R08: dffffc0000000000 R09: ffff88801252e820 R10: ffffed10024a5d06 R11: 0000000000000000 R12: dffffc0000000000 R13: 1ffff920003cfe3f R14: ffffc90001e7f1fc R15: ffffc90001e7f1f8 FS: 00007f6951c24700(0000) GS:ffff8880b9c00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007ffd472d29c0 CR3: 000000002b182000 CR4: 00000000001506f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 ---------------- Code disassembly (best guess): 0: 24 38 and $0x38,%al 2: 42 80 3c 20 00 cmpb $0x0,(%rax,%r12,1) 7: 74 08 je 0x11 9: 48 89 ef mov %rbp,%rdi c: e8 df 15 db ff callq 0xffdb15f0 11: 48 8b 6d 00 mov 0x0(%rbp),%rbp 15: 48 8d 5d 28 lea 0x28(%rbp),%rbx 19: 48 89 d8 mov %rbx,%rax 1c: 48 c1 e8 03 shr $0x3,%rax 20: 48 b9 00 00 00 00 00 movabs $0xdffffc0000000000,%rcx 27: fc ff df * 2a: 80 3c 08 00 cmpb $0x0,(%rax,%rcx,1) <-- trapping instruction 2e: 74 08 je 0x38 30: 48 89 df mov %rbx,%rdi 33: e8 b8 15 db ff callq 0xffdb15f0 38: 4c 8b 23 mov (%rbx),%r12 3b: 49 83 c4 48 add $0x48,%r12 3f: 4c rex.WR --- 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. syzbot can test patches for this issue, for details see: https://goo.gl/tpsmEJ#testing-patches