==================================================================
BUG: KASAN: null-ptr-deref in instrument_atomic_read_write include/linux/instrumented.h:96 [inline]
BUG: KASAN: null-ptr-deref in atomic_try_cmpxchg_acquire include/linux/atomic/atomic-instrumented.h:1300 [inline]
BUG: KASAN: null-ptr-deref in queued_spin_lock include/asm-generic/qspinlock.h:111 [inline]
BUG: KASAN: null-ptr-deref in do_raw_spin_lock include/linux/spinlock.h:187 [inline]
BUG: KASAN: null-ptr-deref in __raw_spin_lock include/linux/spinlock_api_smp.h:134 [inline]
BUG: KASAN: null-ptr-deref in _raw_spin_lock+0x85/0x120 kernel/locking/spinlock.c:154
Write of size 4 at addr 0000000000000750 by task syz.2.236/1093
CPU: 1 UID: 0 PID: 1093 Comm: syz.2.236 Not tainted syzkaller #0 de3e1d1c5728fabb050931035751e453f935abb5
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026
Call Trace:
__dump_stack+0x21/0x30 lib/dump_stack.c:94
dump_stack_lvl+0x140/0x1c0 lib/dump_stack.c:120
print_report+0x3d/0x70 mm/kasan/report.c:484
kasan_report+0x162/0x1a0 mm/kasan/report.c:594
check_region_inline mm/kasan/generic.c:-1 [inline]
kasan_check_range+0x25a/0x2b0 mm/kasan/generic.c:189
__kasan_check_write+0x18/0x20 mm/kasan/shadow.c:37
instrument_atomic_read_write include/linux/instrumented.h:96 [inline]
atomic_try_cmpxchg_acquire include/linux/atomic/atomic-instrumented.h:1300 [inline]
queued_spin_lock include/asm-generic/qspinlock.h:111 [inline]
do_raw_spin_lock include/linux/spinlock.h:187 [inline]
__raw_spin_lock include/linux/spinlock_api_smp.h:134 [inline]
_raw_spin_lock+0x85/0x120 kernel/locking/spinlock.c:154
spin_lock include/linux/spinlock.h:351 [inline]
hv_tlb_flush_enqueue+0xb4/0x290 arch/x86/kvm/hyperv.c:1942
kvm_hv_flush_tlb+0xa0c/0x1f10 arch/x86/kvm/hyperv.c:2141
kvm_hv_hypercall+0xfc8/0x1ca0 arch/x86/kvm/hyperv.c:-1
kvm_emulate_hypercall+0xe6/0x450 arch/x86/kvm/x86.c:10147
__vmx_handle_exit arch/x86/kvm/vmx/vmx.c:6597 [inline]
vmx_handle_exit+0x12c0/0x1b10 arch/x86/kvm/vmx/vmx.c:6614
vcpu_enter_guest arch/x86/kvm/x86.c:11169 [inline]
vcpu_run+0x49f7/0x7840 arch/x86/kvm/x86.c:11330
kvm_arch_vcpu_ioctl_run+0x1167/0x1bd0 arch/x86/kvm/x86.c:11654
kvm_vcpu_ioctl+0xa48/0x1000 virt/kvm/kvm_main.c:4515
vfs_ioctl fs/ioctl.c:51 [inline]
__do_sys_ioctl fs/ioctl.c:907 [inline]
__se_sys_ioctl+0x135/0x1b0 fs/ioctl.c:893
__x64_sys_ioctl+0x7f/0xa0 fs/ioctl.c:893
x64_sys_call+0x1878/0x2ee0 arch/x86/include/generated/asm/syscalls_64.h:17
do_syscall_x64 arch/x86/entry/common.c:47 [inline]
do_syscall_64+0x57/0xf0 arch/x86/entry/common.c:78
entry_SYSCALL_64_after_hwframe+0x76/0x7e
RIP: 0033:0x7febaf99c819
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 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 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007febb08e4028 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007febafc15fa0 RCX: 00007febaf99c819
RDX: 0000000000000000 RSI: 000000000000ae80 RDI: 0000000000000006
RBP: 00007febafa32c91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007febafc16038 R14: 00007febafc15fa0 R15: 00007ffc65775078
==================================================================
BUG: kernel NULL pointer dereference, address: 0000000000000750
#PF: supervisor write access in kernel mode
#PF: error_code(0x0002) - not-present page
PGD 800000011dde4067 P4D 800000011dde4067 PUD 0
Oops: Oops: 0002 [#1] PREEMPT SMP KASAN PTI
CPU: 1 UID: 0 PID: 1093 Comm: syz.2.236 Tainted: G B syzkaller #0 de3e1d1c5728fabb050931035751e453f935abb5
Tainted: [B]=BAD_PAGE
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026
RIP: 0010:arch_atomic_try_cmpxchg arch/x86/include/asm/atomic.h:107 [inline]
RIP: 0010:raw_atomic_try_cmpxchg_acquire include/linux/atomic/atomic-arch-fallback.h:2170 [inline]
RIP: 0010:atomic_try_cmpxchg_acquire include/linux/atomic/atomic-instrumented.h:1302 [inline]
RIP: 0010:queued_spin_lock include/asm-generic/qspinlock.h:111 [inline]
RIP: 0010:do_raw_spin_lock include/linux/spinlock.h:187 [inline]
RIP: 0010:__raw_spin_lock include/linux/spinlock_api_smp.h:134 [inline]
RIP: 0010:_raw_spin_lock+0x9b/0x120 kernel/locking/spinlock.c:154
Code: 04 04 c7 44 24 20 00 00 00 00 be 04 00 00 00 e8 8b 7f 3c fc 4c 89 f7 be 04 00 00 00 e8 7e 7f 3c fc 8b 44 24 20 b9 01 00 00 00 0f b1 0b 75 38 43 c6 44 3c 04 f8 48 c7 04 24 0e 36 e0 45 4b c7
RSP: 0018:ffffc9000337ec00 EFLAGS: 00010297
RAX: 0000000000000000 RBX: 0000000000000750 RCX: 0000000000000001
RDX: 0000000000000001 RSI: 0000000000000004 RDI: ffffc9000337ec20
RBP: ffffc9000337ec90 R08: 0000000000000003 R09: 0000000000000004
R10: dffffc0000000000 R11: fffff5200066fd84 R12: 1ffff9200066fd80
R13: dffffc0000000000 R14: ffffc9000337ec20 R15: dffffc0000000000
FS: 00007febb08e46c0(0000) GS:ffff8881f6f00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000750 CR3: 000000010cfa4000 CR4: 00000000003526b0
Call Trace:
spin_lock include/linux/spinlock.h:351 [inline]
hv_tlb_flush_enqueue+0xb4/0x290 arch/x86/kvm/hyperv.c:1942
kvm_hv_flush_tlb+0xa0c/0x1f10 arch/x86/kvm/hyperv.c:2141
kvm_hv_hypercall+0xfc8/0x1ca0 arch/x86/kvm/hyperv.c:-1
kvm_emulate_hypercall+0xe6/0x450 arch/x86/kvm/x86.c:10147
__vmx_handle_exit arch/x86/kvm/vmx/vmx.c:6597 [inline]
vmx_handle_exit+0x12c0/0x1b10 arch/x86/kvm/vmx/vmx.c:6614
vcpu_enter_guest arch/x86/kvm/x86.c:11169 [inline]
vcpu_run+0x49f7/0x7840 arch/x86/kvm/x86.c:11330
kvm_arch_vcpu_ioctl_run+0x1167/0x1bd0 arch/x86/kvm/x86.c:11654
kvm_vcpu_ioctl+0xa48/0x1000 virt/kvm/kvm_main.c:4515
vfs_ioctl fs/ioctl.c:51 [inline]
__do_sys_ioctl fs/ioctl.c:907 [inline]
__se_sys_ioctl+0x135/0x1b0 fs/ioctl.c:893
__x64_sys_ioctl+0x7f/0xa0 fs/ioctl.c:893
x64_sys_call+0x1878/0x2ee0 arch/x86/include/generated/asm/syscalls_64.h:17
do_syscall_x64 arch/x86/entry/common.c:47 [inline]
do_syscall_64+0x57/0xf0 arch/x86/entry/common.c:78
entry_SYSCALL_64_after_hwframe+0x76/0x7e
RIP: 0033:0x7febaf99c819
Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 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 e8 ff ff ff f7 d8 64 89 01 48
RSP: 002b:00007febb08e4028 EFLAGS: 00000246 ORIG_RAX: 0000000000000010
RAX: ffffffffffffffda RBX: 00007febafc15fa0 RCX: 00007febaf99c819
RDX: 0000000000000000 RSI: 000000000000ae80 RDI: 0000000000000006
RBP: 00007febafa32c91 R08: 0000000000000000 R09: 0000000000000000
R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000
R13: 00007febafc16038 R14: 00007febafc15fa0 R15: 00007ffc65775078
Modules linked in:
CR2: 0000000000000750
---[ end trace 0000000000000000 ]---
RIP: 0010:arch_atomic_try_cmpxchg arch/x86/include/asm/atomic.h:107 [inline]
RIP: 0010:raw_atomic_try_cmpxchg_acquire include/linux/atomic/atomic-arch-fallback.h:2170 [inline]
RIP: 0010:atomic_try_cmpxchg_acquire include/linux/atomic/atomic-instrumented.h:1302 [inline]
RIP: 0010:queued_spin_lock include/asm-generic/qspinlock.h:111 [inline]
RIP: 0010:do_raw_spin_lock include/linux/spinlock.h:187 [inline]
RIP: 0010:__raw_spin_lock include/linux/spinlock_api_smp.h:134 [inline]
RIP: 0010:_raw_spin_lock+0x9b/0x120 kernel/locking/spinlock.c:154
Code: 04 04 c7 44 24 20 00 00 00 00 be 04 00 00 00 e8 8b 7f 3c fc 4c 89 f7 be 04 00 00 00 e8 7e 7f 3c fc 8b 44 24 20 b9 01 00 00 00 0f b1 0b 75 38 43 c6 44 3c 04 f8 48 c7 04 24 0e 36 e0 45 4b c7
RSP: 0018:ffffc9000337ec00 EFLAGS: 00010297
RAX: 0000000000000000 RBX: 0000000000000750 RCX: 0000000000000001
RDX: 0000000000000001 RSI: 0000000000000004 RDI: ffffc9000337ec20
RBP: ffffc9000337ec90 R08: 0000000000000003 R09: 0000000000000004
R10: dffffc0000000000 R11: fffff5200066fd84 R12: 1ffff9200066fd80
R13: dffffc0000000000 R14: ffffc9000337ec20 R15: dffffc0000000000
FS: 00007febb08e46c0(0000) GS:ffff8881f6f00000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000750 CR3: 000000010cfa4000 CR4: 00000000003526b0
----------------
Code disassembly (best guess):
0: 04 04 add $0x4,%al
2: c7 44 24 20 00 00 00 movl $0x0,0x20(%rsp)
9: 00
a: be 04 00 00 00 mov $0x4,%esi
f: e8 8b 7f 3c fc call 0xfc3c7f9f
14: 4c 89 f7 mov %r14,%rdi
17: be 04 00 00 00 mov $0x4,%esi
1c: e8 7e 7f 3c fc call 0xfc3c7f9f
21: 8b 44 24 20 mov 0x20(%rsp),%eax
25: b9 01 00 00 00 mov $0x1,%ecx
* 2a: f0 0f b1 0b lock cmpxchg %ecx,(%rbx) <-- trapping instruction
2e: 75 38 jne 0x68
30: 43 c6 44 3c 04 f8 movb $0xf8,0x4(%r12,%r15,1)
36: 48 c7 04 24 0e 36 e0 movq $0x45e0360e,(%rsp)
3d: 45
3e: 4b rex.WXB
3f: c7 .byte 0xc7