general protection fault, probably for non-canonical address 0xdffffc0000000009: 0000 [#1] PREEMPT SMP KASAN KASAN: null-ptr-deref in range [0x0000000000000048-0x000000000000004f] CPU: 1 PID: 6873 Comm: udevd Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026 RIP: 0010:loopback_jiffies_timer_pos_update+0x13c/0x1250 sound/drivers/aloop.c:619 Code: 77 3d f9 44 89 f8 83 e0 02 44 89 7c 24 3c 75 0a e8 79 73 3d f9 45 31 ff eb 27 e8 6f 73 3d f9 49 8d 5d 48 48 89 d8 48 c1 e8 03 <80> 3c 28 00 74 08 48 89 df e8 46 a2 95 f9 4d 89 f7 4c 2b 3b 4c 89 RSP: 0018:ffffc900001f0ac8 EFLAGS: 00010006 RAX: 0000000000000009 RBX: 0000000000000048 RCX: ffff8880287c0000 RDX: 0000000000000100 RSI: 0000000000000002 RDI: 0000000000000000 RBP: dffffc0000000000 R08: 0000000000000003 R09: 0000000000000004 R10: dffffc0000000000 R11: fffff5200003e148 R12: 0000000000000003 R13: 0000000000000000 R14: 00000000ffffed09 R15: 0000000000000003 FS: 00007f1d51b67880(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000200000032000 CR3: 000000002e9fa000 CR4: 00000000003506e0 Call Trace: loopback_jiffies_timer_function+0x62/0x250 sound/drivers/aloop.c:662 call_timer_fn+0x189/0x540 kernel/time/timer.c:1701 expire_timers kernel/time/timer.c:1752 [inline] __run_timers+0x542/0x800 kernel/time/timer.c:2023 run_timer_softirq+0x67/0xf0 kernel/time/timer.c:2036 handle_softirqs+0x280/0x820 kernel/softirq.c:578 __do_softirq kernel/softirq.c:612 [inline] invoke_softirq kernel/softirq.c:452 [inline] __irq_exit_rcu+0xd3/0x190 kernel/softirq.c:661 irq_exit_rcu+0x9/0x20 kernel/softirq.c:673 instr_sysvec_apic_timer_interrupt arch/x86/kernel/apic/apic.c:1088 [inline] sysvec_apic_timer_interrupt+0xa4/0xc0 arch/x86/kernel/apic/apic.c:1088 asm_sysvec_apic_timer_interrupt+0x1a/0x20 arch/x86/include/asm/idtentry.h:687 RIP: 0010:__sanitizer_cov_trace_switch+0x28/0x120 kernel/kcov.c:-1 Code: c3 90 f3 0f 1e fa 48 8b 06 48 8b 4e 08 48 83 c1 f8 48 c1 c1 3d 48 83 f9 02 7f 1e 48 85 c9 74 3c 48 83 f9 01 0f 85 ee 00 00 00 03 00 00 00 48 85 c0 75 36 e9 df 00 00 00 48 83 f9 03 0f 84 c7 RSP: 0018:ffffc90003857430 EFLAGS: 00000246 RAX: 0000000000000008 RBX: 0000000000000000 RCX: 0000000000000001 RDX: 0000000000000000 RSI: ffffffff8cf9e760 RDI: 0000000000000005 RBP: ffffc90003857558 R08: ffff8880287c0000 R09: 0000000000000002 R10: 0000000000000001 R11: 0000000000000000 R12: ffffc90003857508 R13: dffffc0000000000 R14: 0000000000000005 R15: ffffffff8f18e88a unwind_next_frame+0x742/0x2970 arch/x86/kernel/unwind_orc.c:515 arch_stack_walk+0x144/0x190 arch/x86/kernel/stacktrace.c:25 stack_trace_save+0xaa/0x100 kernel/stacktrace.c:122 kasan_save_stack mm/kasan/common.c:46 [inline] kasan_set_track+0x4e/0x70 mm/kasan/common.c:53 __kasan_slab_alloc+0x6c/0x80 mm/kasan/common.c:329 kasan_slab_alloc include/linux/kasan.h:188 [inline] slab_post_alloc_hook+0x6e/0x4b0 mm/slab.h:767 slab_alloc_node mm/slub.c:3495 [inline] slab_alloc mm/slub.c:3503 [inline] __kmem_cache_alloc_lru mm/slub.c:3510 [inline] kmem_cache_alloc+0x11a/0x2d0 mm/slub.c:3519 kmem_cache_zalloc include/linux/slab.h:711 [inline] alloc_empty_file+0x9e/0x1d0 fs/file_table.c:206 path_openat+0x113/0x3230 fs/namei.c:3783 do_filp_open+0x1f5/0x430 fs/namei.c:3824 do_sys_openat2+0x134/0x1d0 fs/open.c:1421 do_sys_open fs/open.c:1436 [inline] __do_sys_openat fs/open.c:1452 [inline] __se_sys_openat fs/open.c:1447 [inline] __x64_sys_openat+0x139/0x160 fs/open.c:1447 do_syscall_x64 arch/x86/entry/common.c:46 [inline] do_syscall_64+0x55/0xa0 arch/x86/entry/common.c:76 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7f1d514a7407 Code: 48 89 fa 4c 89 df e8 38 aa 00 00 8b 93 08 03 00 00 59 5e 48 83 f8 fc 74 1a 5b c3 0f 1f 84 00 00 00 00 00 48 8b 44 24 10 0f 05 <5b> c3 0f 1f 80 00 00 00 00 83 e2 39 83 fa 08 75 de e8 23 ff ff ff RSP: 002b:00007fffab718ba0 EFLAGS: 00000202 ORIG_RAX: 0000000000000101 RAX: ffffffffffffffda RBX: 00007f1d51b67880 RCX: 00007f1d514a7407 RDX: 0000000000080000 RSI: 00007fffab718d20 RDI: ffffffffffffff9c RBP: 0000000000000008 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000202 R12: 00005597f98f57f5 R13: 00005597f98f57f5 R14: 0000000000000001 R15: 00005597f9910140 Modules linked in: ---[ end trace 0000000000000000 ]--- RIP: 0010:loopback_jiffies_timer_pos_update+0x13c/0x1250 sound/drivers/aloop.c:619 Code: 77 3d f9 44 89 f8 83 e0 02 44 89 7c 24 3c 75 0a e8 79 73 3d f9 45 31 ff eb 27 e8 6f 73 3d f9 49 8d 5d 48 48 89 d8 48 c1 e8 03 <80> 3c 28 00 74 08 48 89 df e8 46 a2 95 f9 4d 89 f7 4c 2b 3b 4c 89 RSP: 0018:ffffc900001f0ac8 EFLAGS: 00010006 RAX: 0000000000000009 RBX: 0000000000000048 RCX: ffff8880287c0000 RDX: 0000000000000100 RSI: 0000000000000002 RDI: 0000000000000000 RBP: dffffc0000000000 R08: 0000000000000003 R09: 0000000000000004 R10: dffffc0000000000 R11: fffff5200003e148 R12: 0000000000000003 R13: 0000000000000000 R14: 00000000ffffed09 R15: 0000000000000003 FS: 00007f1d51b67880(0000) GS:ffff8880b8f00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000200000032000 CR3: 000000002e9fa000 CR4: 00000000003506e0 ---------------- Code disassembly (best guess): 0: 77 3d ja 0x3f 2: f9 stc 3: 44 89 f8 mov %r15d,%eax 6: 83 e0 02 and $0x2,%eax 9: 44 89 7c 24 3c mov %r15d,0x3c(%rsp) e: 75 0a jne 0x1a 10: e8 79 73 3d f9 call 0xf93d738e 15: 45 31 ff xor %r15d,%r15d 18: eb 27 jmp 0x41 1a: e8 6f 73 3d f9 call 0xf93d738e 1f: 49 8d 5d 48 lea 0x48(%r13),%rbx 23: 48 89 d8 mov %rbx,%rax 26: 48 c1 e8 03 shr $0x3,%rax * 2a: 80 3c 28 00 cmpb $0x0,(%rax,%rbp,1) <-- trapping instruction 2e: 74 08 je 0x38 30: 48 89 df mov %rbx,%rdi 33: e8 46 a2 95 f9 call 0xf995a27e 38: 4d 89 f7 mov %r14,%r15 3b: 4c 2b 3b sub (%rbx),%r15 3e: 4c rex.WR 3f: 89 .byte 0x89