Code: Unable to access opcode bytes at RIP 0x7f5c0d2b493f. RSP: 002b:00007f5c0b91cfe8 EFLAGS: 00000246 ORIG_RAX: 0000000000000038 RAX: 0000000000000000 RBX: 00007f5c0d4dbfa0 RCX: 00007f5c0d2b4969 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 00007f5c0d336ab1 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000001 R14: 00007f5c0d4dbfa0 R15: 00007ffd82017108 ---[ end trace d3bc3a57edc6baf6 ]--- ================================================================== BUG: KASAN: null-ptr-deref in instrument_atomic_read_write include/linux/instrumented.h:101 [inline] BUG: KASAN: null-ptr-deref in atomic_inc_return include/asm-generic/atomic-instrumented.h:250 [inline] BUG: KASAN: null-ptr-deref in ihold+0x20/0x60 fs/inode.c:423 Write of size 4 at addr 0000000000000170 by task syz.4.38/485 CPU: 0 PID: 485 Comm: syz.4.38 Tainted: G W 5.10.236-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025 Call Trace: __dump_stack+0x21/0x24 lib/dump_stack.c:77 dump_stack_lvl+0x169/0x1d8 lib/dump_stack.c:118 __kasan_report mm/kasan/report.c:439 [inline] kasan_report+0xd8/0x130 mm/kasan/report.c:452 check_region_inline mm/kasan/generic.c:-1 [inline] kasan_check_range+0x280/0x290 mm/kasan/generic.c:189 __kasan_check_write+0x14/0x20 mm/kasan/shadow.c:37 instrument_atomic_read_write include/linux/instrumented.h:101 [inline] atomic_inc_return include/asm-generic/atomic-instrumented.h:250 [inline] ihold+0x20/0x60 fs/inode.c:423 d_delete_notify include/linux/fsnotify.h:264 [inline] vfs_rmdir+0x247/0x3e0 fs/namei.c:3865 incfs_kill_sb+0xfe/0x210 fs/incfs/vfs.c:1973 deactivate_locked_super+0xa0/0x100 fs/super.c:335 deactivate_super+0xaf/0xe0 fs/super.c:366 cleanup_mnt+0x446/0x500 fs/namespace.c:1118 __cleanup_mnt+0x19/0x20 fs/namespace.c:1125 task_work_run+0x127/0x190 kernel/task_work.c:189 exit_task_work include/linux/task_work.h:33 [inline] do_exit+0xa27/0x2470 kernel/exit.c:863 do_group_exit+0x141/0x310 kernel/exit.c:985 get_signal+0xf7d/0x12e0 kernel/signal.c:2793 arch_do_signal_or_restart+0xbf/0x10f0 arch/x86/kernel/signal.c:805 handle_signal_work kernel/entry/common.c:145 [inline] exit_to_user_mode_loop+0xa2/0xe0 kernel/entry/common.c:169 exit_to_user_mode_prepare kernel/entry/common.c:199 [inline] syscall_exit_to_user_mode+0x68/0x90 kernel/entry/common.c:274 ret_from_fork+0x15/0x30 arch/x86/entry/entry_64.S:291 RIP: 0033:0x7f5c0d2b4969 Code: Unable to access opcode bytes at RIP 0x7f5c0d2b493f. RSP: 002b:00007f5c0b91cfe8 EFLAGS: 00000246 ORIG_RAX: 0000000000000038 RAX: 0000000000000000 RBX: 00007f5c0d4dbfa0 RCX: 00007f5c0d2b4969 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 00007f5c0d336ab1 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000001 R14: 00007f5c0d4dbfa0 R15: 00007ffd82017108 ================================================================== BUG: kernel NULL pointer dereference, address: 0000000000000170 #PF: supervisor write access in kernel mode #PF: error_code(0x0002) - not-present page PGD 113537067 P4D 113537067 PUD 0 Oops: 0002 [#1] PREEMPT SMP KASAN CPU: 0 PID: 485 Comm: syz.4.38 Tainted: G B W 5.10.236-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025 RIP: 0010:arch_atomic_add_return arch/x86/include/asm/atomic.h:165 [inline] RIP: 0010:arch_atomic_inc_return include/linux/atomic-arch-fallback.h:286 [inline] RIP: 0010:atomic_inc_return include/asm-generic/atomic-instrumented.h:251 [inline] RIP: 0010:ihold+0x26/0x60 fs/inode.c:423 Code: 00 00 00 00 55 48 89 e5 41 56 53 48 89 fb e8 41 33 b8 ff 48 8d bb 70 01 00 00 be 04 00 00 00 e8 90 1b f2 ff 41 be 01 00 00 00 44 0f c1 b3 70 01 00 00 41 ff c6 bf 02 00 00 00 44 89 f6 e8 c1 RSP: 0018:ffffc90007a478a8 EFLAGS: 00010246 RAX: ffff88810f853b00 RBX: 0000000000000000 RCX: 0000000000000282 RDX: 0000000000000000 RSI: 0000000000000002 RDI: 00000000ffffffff RBP: ffffc90007a478b8 R08: 0000000000000004 R09: 0000000000000003 R10: fffffbfff0d8e448 R11: 1ffffffff0d8e448 R12: 1ffff11021fc9eb0 R13: 0000000000000000 R14: 0000000000000001 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff8881f7000000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000170 CR3: 0000000114493000 CR4: 00000000003506b0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: d_delete_notify include/linux/fsnotify.h:264 [inline] vfs_rmdir+0x247/0x3e0 fs/namei.c:3865 incfs_kill_sb+0xfe/0x210 fs/incfs/vfs.c:1973 deactivate_locked_super+0xa0/0x100 fs/super.c:335 deactivate_super+0xaf/0xe0 fs/super.c:366 cleanup_mnt+0x446/0x500 fs/namespace.c:1118 __cleanup_mnt+0x19/0x20 fs/namespace.c:1125 task_work_run+0x127/0x190 kernel/task_work.c:189 exit_task_work include/linux/task_work.h:33 [inline] do_exit+0xa27/0x2470 kernel/exit.c:863 do_group_exit+0x141/0x310 kernel/exit.c:985 get_signal+0xf7d/0x12e0 kernel/signal.c:2793 arch_do_signal_or_restart+0xbf/0x10f0 arch/x86/kernel/signal.c:805 handle_signal_work kernel/entry/common.c:145 [inline] exit_to_user_mode_loop+0xa2/0xe0 kernel/entry/common.c:169 exit_to_user_mode_prepare kernel/entry/common.c:199 [inline] syscall_exit_to_user_mode+0x68/0x90 kernel/entry/common.c:274 ret_from_fork+0x15/0x30 arch/x86/entry/entry_64.S:291 RIP: 0033:0x7f5c0d2b4969 Code: Unable to access opcode bytes at RIP 0x7f5c0d2b493f. RSP: 002b:00007f5c0b91cfe8 EFLAGS: 00000246 ORIG_RAX: 0000000000000038 RAX: 0000000000000000 RBX: 00007f5c0d4dbfa0 RCX: 00007f5c0d2b4969 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 00007f5c0d336ab1 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000001 R14: 00007f5c0d4dbfa0 R15: 00007ffd82017108 Modules linked in: CR2: 0000000000000170 ---[ end trace d3bc3a57edc6baf7 ]--- RIP: 0010:arch_atomic_add_return arch/x86/include/asm/atomic.h:165 [inline] RIP: 0010:arch_atomic_inc_return include/linux/atomic-arch-fallback.h:286 [inline] RIP: 0010:atomic_inc_return include/asm-generic/atomic-instrumented.h:251 [inline] RIP: 0010:ihold+0x26/0x60 fs/inode.c:423 Code: 00 00 00 00 55 48 89 e5 41 56 53 48 89 fb e8 41 33 b8 ff 48 8d bb 70 01 00 00 be 04 00 00 00 e8 90 1b f2 ff 41 be 01 00 00 00 44 0f c1 b3 70 01 00 00 41 ff c6 bf 02 00 00 00 44 89 f6 e8 c1 RSP: 0018:ffffc90007a478a8 EFLAGS: 00010246 RAX: ffff88810f853b00 RBX: 0000000000000000 RCX: 0000000000000282 RDX: 0000000000000000 RSI: 0000000000000002 RDI: 00000000ffffffff RBP: ffffc90007a478b8 R08: 0000000000000004 R09: 0000000000000003 R10: fffffbfff0d8e448 R11: 1ffffffff0d8e448 R12: 1ffff11021fc9eb0 R13: 0000000000000000 R14: 0000000000000001 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff8881f7000000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000170 CR3: 0000000114493000 CR4: 00000000003506b0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 ---------------- Code disassembly (best guess): 0: 00 00 add %al,(%rax) 2: 00 00 add %al,(%rax) 4: 55 push %rbp 5: 48 89 e5 mov %rsp,%rbp 8: 41 56 push %r14 a: 53 push %rbx b: 48 89 fb mov %rdi,%rbx e: e8 41 33 b8 ff call 0xffb83354 13: 48 8d bb 70 01 00 00 lea 0x170(%rbx),%rdi 1a: be 04 00 00 00 mov $0x4,%esi 1f: e8 90 1b f2 ff call 0xfff21bb4 24: 41 be 01 00 00 00 mov $0x1,%r14d * 2a: f0 44 0f c1 b3 70 01 lock xadd %r14d,0x170(%rbx) <-- trapping instruction 31: 00 00 33: 41 ff c6 inc %r14d 36: bf 02 00 00 00 mov $0x2,%edi 3b: 44 89 f6 mov %r14d,%esi 3e: e8 .byte 0xe8 3f: c1 .byte 0xc1