Oops: general protection fault, probably for non-canonical address 0xdffffc0000000001: 0000 [#1] SMP KASAN PTI KASAN: null-ptr-deref in range [0x0000000000000008-0x000000000000000f] CPU: 1 UID: 0 PID: 31182 Comm: syz.3.6014 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025 RIP: 0010:_compound_head include/linux/page-flags.h:284 [inline] RIP: 0010:io_check_coalesce_buffer+0x354/0xb60 io_uring/rsrc.c:746 Code: f7 e8 e0 6e 62 fd 4c 89 74 24 28 48 8b 44 24 18 4c 8b 74 d8 08 49 8d 6e 08 48 89 e8 48 c1 e8 03 48 b9 00 00 00 00 00 fc ff df <80> 3c 08 00 74 08 48 89 ef e8 ae 6e 62 fd 48 8b 6d 00 48 89 ee 48 RSP: 0018:ffffc90004fbfa38 EFLAGS: 00010202 RAX: 0000000000000001 RBX: 00000000000000a4 RCX: dffffc0000000000 RDX: ffffc90017bef000 RSI: 0000000000000d8a RDI: 0000000000000d8b RBP: 0000000000000008 R08: ffffea00010e0007 R09: 1ffffd400021c000 R10: dffffc0000000000 R11: fffff9400021c001 R12: ffff888047f9e520 R13: 00000000000000a5 R14: 0000000000000000 R15: ffffea00010e0000 FS: 00007f15420ae6c0(0000) GS:ffff8881258bd000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000000 CR3: 00000000482c2000 CR4: 00000000003526f0 Call Trace: io_region_init_ptr+0xdb/0x350 io_uring/memmap.c:119 io_create_region+0x3a4/0x480 io_uring/memmap.c:228 io_allocate_scq_urings+0x2b0/0x870 io_uring/io_uring.c:3626 io_uring_create+0x591/0xba0 io_uring/io_uring.c:3867 io_uring_setup io_uring/io_uring.c:3958 [inline] __do_sys_io_uring_setup io_uring/io_uring.c:3992 [inline] __se_sys_io_uring_setup+0x264/0x270 io_uring/io_uring.c:3983 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xfa/0xfa0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f154118ebe9 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 a8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007f15420adfc8 EFLAGS: 00000206 ORIG_RAX: 00000000000001a9 RAX: ffffffffffffffda RBX: 00007f15413c5fa0 RCX: 00007f154118ebe9 RDX: 0000000000000000 RSI: 0000200000000040 RDI: 0000000000005b14 RBP: 0000200000000040 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000206 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000005b14 R15: 0000000000000000 Modules linked in: ---[ end trace 0000000000000000 ]--- RIP: 0010:_compound_head include/linux/page-flags.h:284 [inline] RIP: 0010:io_check_coalesce_buffer+0x354/0xb60 io_uring/rsrc.c:746 Code: f7 e8 e0 6e 62 fd 4c 89 74 24 28 48 8b 44 24 18 4c 8b 74 d8 08 49 8d 6e 08 48 89 e8 48 c1 e8 03 48 b9 00 00 00 00 00 fc ff df <80> 3c 08 00 74 08 48 89 ef e8 ae 6e 62 fd 48 8b 6d 00 48 89 ee 48 RSP: 0018:ffffc90004fbfa38 EFLAGS: 00010202 RAX: 0000000000000001 RBX: 00000000000000a4 RCX: dffffc0000000000 RDX: ffffc90017bef000 RSI: 0000000000000d8a RDI: 0000000000000d8b RBP: 0000000000000008 R08: ffffea00010e0007 R09: 1ffffd400021c000 R10: dffffc0000000000 R11: fffff9400021c001 R12: ffff888047f9e520 R13: 00000000000000a5 R14: 0000000000000000 R15: ffffea00010e0000 FS: 00007f15420ae6c0(0000) GS:ffff8881258bd000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fb6b0120ff0 CR3: 00000000482c2000 CR4: 00000000003526f0 ---------------- Code disassembly (best guess), 1 bytes skipped: 0: e8 e0 6e 62 fd call 0xfd626ee5 5: 4c 89 74 24 28 mov %r14,0x28(%rsp) a: 48 8b 44 24 18 mov 0x18(%rsp),%rax f: 4c 8b 74 d8 08 mov 0x8(%rax,%rbx,8),%r14 14: 49 8d 6e 08 lea 0x8(%r14),%rbp 18: 48 89 e8 mov %rbp,%rax 1b: 48 c1 e8 03 shr $0x3,%rax 1f: 48 b9 00 00 00 00 00 movabs $0xdffffc0000000000,%rcx 26: fc ff df * 29: 80 3c 08 00 cmpb $0x0,(%rax,%rcx,1) <-- trapping instruction 2d: 74 08 je 0x37 2f: 48 89 ef mov %rbp,%rdi 32: e8 ae 6e 62 fd call 0xfd626ee5 37: 48 8b 6d 00 mov 0x0(%rbp),%rbp 3b: 48 89 ee mov %rbp,%rsi 3e: 48 rex.W