RBP: 00007fffbe202f90 R08: 0000000000000000 R09: 0000000000000000 R10: 00000000ffffffff R11: 0000000000000206 R12: 00007fffbe204000 R13: 000055556ea256c0 R14: 00007fffbe204000 R15: 0000000000000001 ---[ end trace c8397d1ffaa099ab ]--- ================================================================== BUG: KASAN: null-ptr-deref in atomic_add_return include/asm-generic/atomic-instrumented.h:71 [inline] BUG: KASAN: null-ptr-deref in atomic_inc_return include/linux/atomic-fallback.h:284 [inline] BUG: KASAN: null-ptr-deref in ihold+0x1b/0x50 fs/inode.c:421 Write of size 4 at addr 0000000000000160 by task syz-executor409/359 CPU: 1 PID: 359 Comm: syz-executor409 Tainted: G W 5.4.289-syzkaller-00025-g49530c73f82d #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 12/27/2024 Call Trace: __dump_stack lib/dump_stack.c:77 [inline] dump_stack+0x1d8/0x241 lib/dump_stack.c:118 __kasan_report+0xe9/0x120 mm/kasan/report.c:520 kasan_report+0x30/0x60 mm/kasan/common.c:653 check_memory_region_inline mm/kasan/generic.c:141 [inline] check_memory_region+0x272/0x280 mm/kasan/generic.c:191 atomic_add_return include/asm-generic/atomic-instrumented.h:71 [inline] atomic_inc_return include/linux/atomic-fallback.h:284 [inline] ihold+0x1b/0x50 fs/inode.c:421 d_delete_notify include/linux/fsnotify.h:227 [inline] vfs_rmdir+0x1e0/0x3c0 fs/namei.c:4040 incfs_kill_sb+0x105/0x200 fs/incfs/vfs.c:1944 deactivate_locked_super+0xa8/0x110 fs/super.c:335 deactivate_super+0x1e2/0x2a0 fs/super.c:366 cleanup_mnt+0x44e/0x500 fs/namespace.c:1102 task_work_run+0x140/0x170 kernel/task_work.c:113 ptrace_notify+0x29e/0x350 kernel/signal.c:2274 ptrace_report_syscall include/linux/tracehook.h:66 [inline] tracehook_report_syscall_exit include/linux/tracehook.h:129 [inline] syscall_slow_exit_work+0x167/0x400 arch/x86/entry/common.c:246 syscall_return_slowpath arch/x86/entry/common.c:271 [inline] do_syscall_64+0x19d/0x1c0 arch/x86/entry/common.c:300 entry_SYSCALL_64_after_hwframe+0x5c/0xc1 RIP: 0033:0x7f85b678aa87 Code: 07 00 48 83 c4 08 5b 5d c3 66 2e 0f 1f 84 00 00 00 00 00 c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 b8 a6 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 01 c3 48 c7 c2 b8 ff ff ff f7 d8 64 89 02 b8 RSP: 002b:00007fffbe202ed8 EFLAGS: 00000206 ORIG_RAX: 00000000000000a6 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 00007f85b678aa87 RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007fffbe202f90 RBP: 00007fffbe202f90 R08: 0000000000000000 R09: 0000000000000000 R10: 00000000ffffffff R11: 0000000000000206 R12: 00007fffbe204000 R13: 000055556ea256c0 R14: 00007fffbe204000 R15: 0000000000000001 ================================================================== BUG: kernel NULL pointer dereference, address: 0000000000000160 #PF: supervisor write access in kernel mode #PF: error_code(0x0002) - not-present page PGD 0 P4D 0 Oops: 0002 [#1] PREEMPT SMP KASAN CPU: 1 PID: 359 Comm: syz-executor409 Tainted: G B W 5.4.289-syzkaller-00025-g49530c73f82d #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 12/27/2024 RIP: 0010:arch_atomic_add_return arch/x86/include/asm/atomic.h:167 [inline] RIP: 0010:atomic_add_return include/asm-generic/atomic-instrumented.h:72 [inline] RIP: 0010:atomic_inc_return include/linux/atomic-fallback.h:284 [inline] RIP: 0010:ihold+0x20/0x50 fs/inode.c:421 Code: 0f 1f 84 00 00 00 00 00 66 90 55 53 48 89 fb e8 46 d4 c2 ff 48 8d bb 60 01 00 00 be 04 00 00 00 e8 d5 91 f2 ff bd 01 00 00 00 <f0> 0f c1 ab 60 01 00 00 ff c5 bf 02 00 00 00 89 ee e8 0a d7 c2 ff RSP: 0018:ffff8881dbe37ba0 EFLAGS: 00010246 RAX: 0000000000000000 RBX: 0000000000000000 RCX: ffff8881dbe00000 RDX: 0000000000000000 RSI: 0000000000000002 RDI: 00000000ffffffff RBP: 0000000000000001 R08: ffffffff813ae535 R09: 0000000000000003 R10: ffffffffffffffff R11: dffffc0000000001 R12: 0000000000000000 R13: dffffc0000000000 R14: ffff8881e0f61f98 R15: 0000000000000000 FS: 000055556ea24380(0000) GS:ffff8881f6f00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000160 CR3: 00000001d98af000 CR4: 00000000003406a0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: d_delete_notify include/linux/fsnotify.h:227 [inline] vfs_rmdir+0x1e0/0x3c0 fs/namei.c:4040 incfs_kill_sb+0x105/0x200 fs/incfs/vfs.c:1944 deactivate_locked_super+0xa8/0x110 fs/super.c:335 deactivate_super+0x1e2/0x2a0 fs/super.c:366 cleanup_mnt+0x44e/0x500 fs/namespace.c:1102 task_work_run+0x140/0x170 kernel/task_work.c:113 ptrace_notify+0x29e/0x350 kernel/signal.c:2274 ptrace_report_syscall include/linux/tracehook.h:66 [inline] tracehook_report_syscall_exit include/linux/tracehook.h:129 [inline] syscall_slow_exit_work+0x167/0x400 arch/x86/entry/common.c:246 syscall_return_slowpath arch/x86/entry/common.c:271 [inline] do_syscall_64+0x19d/0x1c0 arch/x86/entry/common.c:300 entry_SYSCALL_64_after_hwframe+0x5c/0xc1 RIP: 0033:0x7f85b678aa87 Code: 07 00 48 83 c4 08 5b 5d c3 66 2e 0f 1f 84 00 00 00 00 00 c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 b8 a6 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 01 c3 48 c7 c2 b8 ff ff ff f7 d8 64 89 02 b8 RSP: 002b:00007fffbe202ed8 EFLAGS: 00000206 ORIG_RAX: 00000000000000a6 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 00007f85b678aa87 RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007fffbe202f90 RBP: 00007fffbe202f90 R08: 0000000000000000 R09: 0000000000000000 R10: 00000000ffffffff R11: 0000000000000206 R12: 00007fffbe204000 R13: 000055556ea256c0 R14: 00007fffbe204000 R15: 0000000000000001 Modules linked in: CR2: 0000000000000160 ---[ end trace c8397d1ffaa099ac ]--- RIP: 0010:arch_atomic_add_return arch/x86/include/asm/atomic.h:167 [inline] RIP: 0010:atomic_add_return include/asm-generic/atomic-instrumented.h:72 [inline] RIP: 0010:atomic_inc_return include/linux/atomic-fallback.h:284 [inline] RIP: 0010:ihold+0x20/0x50 fs/inode.c:421 Code: 0f 1f 84 00 00 00 00 00 66 90 55 53 48 89 fb e8 46 d4 c2 ff 48 8d bb 60 01 00 00 be 04 00 00 00 e8 d5 91 f2 ff bd 01 00 00 00 <f0> 0f c1 ab 60 01 00 00 ff c5 bf 02 00 00 00 89 ee e8 0a d7 c2 ff RSP: 0018:ffff8881dbe37ba0 EFLAGS: 00010246 RAX: 0000000000000000 RBX: 0000000000000000 RCX: ffff8881dbe00000 RDX: 0000000000000000 RSI: 0000000000000002 RDI: 00000000ffffffff RBP: 0000000000000001 R08: ffffffff813ae535 R09: 0000000000000003 R10: ffffffffffffffff R11: dffffc0000000001 R12: 0000000000000000 R13: dffffc0000000000 R14: ffff8881e0f61f98 R15: 0000000000000000 FS: 000055556ea24380(0000) GS:ffff8881f6f00000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000160 CR3: 00000001d98af000 CR4: 00000000003406a0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 ---------------- Code disassembly (best guess): 0: 0f 1f 84 00 00 00 00 nopl 0x0(%rax,%rax,1) 7: 00 8: 66 90 xchg %ax,%ax a: 55 push %rbp b: 53 push %rbx c: 48 89 fb mov %rdi,%rbx f: e8 46 d4 c2 ff call 0xffc2d45a 14: 48 8d bb 60 01 00 00 lea 0x160(%rbx),%rdi 1b: be 04 00 00 00 mov $0x4,%esi 20: e8 d5 91 f2 ff call 0xfff291fa 25: bd 01 00 00 00 mov $0x1,%ebp * 2a: f0 0f c1 ab 60 01 00 lock xadd %ebp,0x160(%rbx) <-- trapping instruction 31: 00 32: ff c5 inc %ebp 34: bf 02 00 00 00 mov $0x2,%edi 39: 89 ee mov %ebp,%esi 3b: e8 0a d7 c2 ff call 0xffc2d74a