Oops: general protection fault, probably for non-canonical address 0xdffffc0000000000: 0000 [#1] PREEMPT SMP KASAN PTI KASAN: null-ptr-deref in range [0x0000000000000000-0x0000000000000007] CPU: 1 UID: 0 PID: 9313 Comm: iou-sqp-9308 Not tainted 6.14.0-rc3-next-20250218-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025 RIP: 0010:native_tss_update_io_bitmap+0x1f5/0x640 arch/x86/kernel/process.c:471 Code: ff df 48 89 44 24 50 42 80 3c 38 00 74 08 48 89 df e8 cf 75 c7 00 48 89 5c 24 58 4c 8b 2b 4c 89 f0 48 c1 e8 03 48 89 44 24 48 <42> 80 3c 38 00 74 08 4c 89 f7 e8 ac 75 c7 00 49 8b 1e 4c 89 ef 48 RSP: 0018:ffffc9000d987280 EFLAGS: 00010246 RAX: 0000000000000000 RBX: ffff8880b870a068 RCX: dffffc0000000000 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000003 RBP: ffffc9000d987380 R08: ffffffff81620a34 R09: 1ffff110066b1780 R10: dffffc0000000000 R11: ffffed10066b1781 R12: 1ffff92001b30e5c R13: 00000000000006b4 R14: 0000000000000000 R15: dffffc0000000000 FS: 000055558a4b9380(0000) GS:ffff8880b8700000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fa9ac187110 CR3: 0000000024a30000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: task_update_io_bitmap+0xb8/0xf0 arch/x86/kernel/ioport.c:47 io_bitmap_exit+0x62/0xf0 arch/x86/kernel/ioport.c:57 exit_thread+0x76/0xa0 arch/x86/kernel/process.c:123 copy_process+0x277d/0x3cf0 kernel/fork.c:2638 create_io_thread+0x16a/0x1e0 kernel/fork.c:2746 create_io_worker+0x176/0x540 io_uring/io-wq.c:862 io_wq_create_worker io_uring/io-wq.c:332 [inline] io_wq_enqueue+0x7b5/0xa00 io_uring/io-wq.c:989 io_queue_iowq+0x433/0x670 io_uring/io_uring.c:542 io_submit_state_end io_uring/io_uring.c:2215 [inline] io_submit_sqes+0x1940/0x1cf0 io_uring/io_uring.c:2335 __io_sq_thread io_uring/sqpoll.c:189 [inline] io_sq_thread+0xc8c/0x1fd0 io_uring/sqpoll.c:312 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:148 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Modules linked in: ---[ end trace 0000000000000000 ]--- RIP: 0010:native_tss_update_io_bitmap+0x1f5/0x640 arch/x86/kernel/process.c:471 Code: ff df 48 89 44 24 50 42 80 3c 38 00 74 08 48 89 df e8 cf 75 c7 00 48 89 5c 24 58 4c 8b 2b 4c 89 f0 48 c1 e8 03 48 89 44 24 48 <42> 80 3c 38 00 74 08 4c 89 f7 e8 ac 75 c7 00 49 8b 1e 4c 89 ef 48 RSP: 0018:ffffc9000d987280 EFLAGS: 00010246 RAX: 0000000000000000 RBX: ffff8880b870a068 RCX: dffffc0000000000 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000003 RBP: ffffc9000d987380 R08: ffffffff81620a34 R09: 1ffff110066b1780 R10: dffffc0000000000 R11: ffffed10066b1781 R12: 1ffff92001b30e5c R13: 00000000000006b4 R14: 0000000000000000 R15: dffffc0000000000 FS: 000055558a4b9380(0000) GS:ffff8880b8700000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00007fa9ac187110 CR3: 0000000024a30000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 ---------------- Code disassembly (best guess), 1 bytes skipped: 0: df 48 89 fisttps -0x77(%rax) 3: 44 24 50 rex.R and $0x50,%al 6: 42 80 3c 38 00 cmpb $0x0,(%rax,%r15,1) b: 74 08 je 0x15 d: 48 89 df mov %rbx,%rdi 10: e8 cf 75 c7 00 call 0xc775e4 15: 48 89 5c 24 58 mov %rbx,0x58(%rsp) 1a: 4c 8b 2b mov (%rbx),%r13 1d: 4c 89 f0 mov %r14,%rax 20: 48 c1 e8 03 shr $0x3,%rax 24: 48 89 44 24 48 mov %rax,0x48(%rsp) * 29: 42 80 3c 38 00 cmpb $0x0,(%rax,%r15,1) <-- trapping instruction 2e: 74 08 je 0x38 30: 4c 89 f7 mov %r14,%rdi 33: e8 ac 75 c7 00 call 0xc775e4 38: 49 8b 1e mov (%r14),%rbx 3b: 4c 89 ef mov %r13,%rdi 3e: 48 rex.W