general protection fault, probably for non-canonical address 0xdffffc0000000000: 0000 [#1] PREEMPT SMP KASAN KASAN: null-ptr-deref in range [0x0000000000000000-0x0000000000000007] CPU: 1 PID: 15912 Comm: syz-executor.4 Not tainted 6.0.0-rc2-next-20220826-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/22/2022 RIP: 0010:__io_sync_cancel+0x10d/0x1c0 io_uring/cancel.c:224 Code: 48 c1 ea 03 80 3c 02 00 0f 85 aa 00 00 00 49 8b 86 f8 00 00 00 48 8d 1c d8 48 b8 00 00 00 00 00 fc ff df 48 89 da 48 c1 ea 03 <80> 3c 02 00 0f 85 8e 00 00 00 48 8b 1b 48 8d 7d 08 48 b8 00 00 00 RSP: 0018:ffffc900044dfc20 EFLAGS: 00010246 RAX: dffffc0000000000 RBX: 0000000000000000 RCX: ffffc9000e66c000 RDX: 0000000000000000 RSI: ffffffff83f98824 RDI: ffff8880354ea0f8 RBP: ffffc900044dfce0 R08: 0000000000000004 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000001 R12: 0000000000000000 R13: ffff88807552f800 R14: ffff8880354ea000 R15: 0000000000000000 FS: 00007fd8c7f02700(0000) GS:ffff8880b9b00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007f288416a1b8 CR3: 0000000076528000 CR4: 00000000003506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: io_sync_cancel+0x240/0x630 io_uring/cancel.c:265 __io_uring_register io_uring/io_uring.c:3833 [inline] __do_sys_io_uring_register+0x5c9/0x1110 io_uring/io_uring.c:3878 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x35/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd RIP: 0033:0x7fd8c6e89279 Code: ff ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 40 00 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 b8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007fd8c7f02168 EFLAGS: 00000246 ORIG_RAX: 00000000000001ab RAX: ffffffffffffffda RBX: 00007fd8c6f9bf80 RCX: 00007fd8c6e89279 RDX: 0000000020000000 RSI: 0000000000000018 RDI: 000000000000000a RBP: 00007fd8c6ee3189 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000001 R11: 0000000000000246 R12: 0000000000000000 R13: 00007ffcf822540f R14: 00007fd8c7f02300 R15: 0000000000022000 Modules linked in: ---[ end trace 0000000000000000 ]--- RIP: 0010:__io_sync_cancel+0x10d/0x1c0 io_uring/cancel.c:224 Code: 48 c1 ea 03 80 3c 02 00 0f 85 aa 00 00 00 49 8b 86 f8 00 00 00 48 8d 1c d8 48 b8 00 00 00 00 00 fc ff df 48 89 da 48 c1 ea 03 <80> 3c 02 00 0f 85 8e 00 00 00 48 8b 1b 48 8d 7d 08 48 b8 00 00 00 RSP: 0018:ffffc900044dfc20 EFLAGS: 00010246 RAX: dffffc0000000000 RBX: 0000000000000000 RCX: ffffc9000e66c000 RDX: 0000000000000000 RSI: ffffffff83f98824 RDI: ffff8880354ea0f8 RBP: ffffc900044dfce0 R08: 0000000000000004 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000001 R12: 0000000000000000 R13: ffff88807552f800 R14: ffff8880354ea000 R15: 0000000000000000 FS: 00007fd8c7f02700(0000) GS:ffff8880b9b00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000000002000e030 CR3: 0000000076528000 CR4: 00000000003506e0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 ---------------- Code disassembly (best guess): 0: 48 c1 ea 03 shr $0x3,%rdx 4: 80 3c 02 00 cmpb $0x0,(%rdx,%rax,1) 8: 0f 85 aa 00 00 00 jne 0xb8 e: 49 8b 86 f8 00 00 00 mov 0xf8(%r14),%rax 15: 48 8d 1c d8 lea (%rax,%rbx,8),%rbx 19: 48 b8 00 00 00 00 00 movabs $0xdffffc0000000000,%rax 20: fc ff df 23: 48 89 da mov %rbx,%rdx 26: 48 c1 ea 03 shr $0x3,%rdx * 2a: 80 3c 02 00 cmpb $0x0,(%rdx,%rax,1) <-- trapping instruction 2e: 0f 85 8e 00 00 00 jne 0xc2 34: 48 8b 1b mov (%rbx),%rbx 37: 48 8d 7d 08 lea 0x8(%rbp),%rdi 3b: 48 rex.W 3c: b8 .byte 0xb8 3d: 00 00 add %al,(%rax)