RBP: 00007f6e6b010ab1 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000000 R13: 0000000000000001 R14: 00007f6e6b1b5fa0 R15: 00007ffd05543728 ---[ end trace 0000000000000000 ]--- ================================================================== BUG: KASAN: null-ptr-deref in instrument_atomic_read_write include/linux/instrumented.h:102 [inline] BUG: KASAN: null-ptr-deref in atomic_inc_return include/linux/atomic/atomic-instrumented.h:198 [inline] BUG: KASAN: null-ptr-deref in ihold+0x20/0x60 fs/inode.c:452 Write of size 4 at addr 0000000000000170 by task syz.4.5870/22148 CPU: 0 PID: 22148 Comm: syz.4.5870 Tainted: G W 6.1.134-syzkaller-00014-g3cd01bb5bd37 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/19/2025 Call Trace: __dump_stack+0x21/0x24 lib/dump_stack.c:88 dump_stack_lvl+0xee/0x150 lib/dump_stack.c:106 print_report+0x3d/0x60 mm/kasan/report.c:430 kasan_report+0x122/0x150 mm/kasan/report.c:531 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:102 [inline] atomic_inc_return include/linux/atomic/atomic-instrumented.h:198 [inline] ihold+0x20/0x60 fs/inode.c:452 d_delete_notify include/linux/fsnotify.h:289 [inline] vfs_rmdir+0x25f/0x500 fs/namei.c:4203 incfs_kill_sb+0x105/0x220 fs/incfs/vfs.c:1995 deactivate_locked_super+0xb5/0x120 fs/super.c:334 deactivate_super+0xaf/0xe0 fs/super.c:365 cleanup_mnt+0x45f/0x4e0 fs/namespace.c:1186 __cleanup_mnt+0x19/0x20 fs/namespace.c:1193 task_work_run+0x1db/0x240 kernel/task_work.c:203 exit_task_work include/linux/task_work.h:39 [inline] do_exit+0xa1d/0x2650 kernel/exit.c:877 do_group_exit+0x210/0x2d0 kernel/exit.c:1027 get_signal+0x13b5/0x1520 kernel/signal.c:2889 arch_do_signal_or_restart+0xb0/0x1030 arch/x86/kernel/signal.c:871 exit_to_user_mode_loop+0x7a/0xb0 kernel/entry/common.c:174 exit_to_user_mode_prepare+0x5a/0xa0 kernel/entry/common.c:210 __syscall_exit_to_user_mode_work kernel/entry/common.c:292 [inline] syscall_exit_to_user_mode+0x1a/0x30 kernel/entry/common.c:303 do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:87 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7f6e6afc1225 Code: Unable to access opcode bytes at 0x7f6e6afc11fb. RSP: 002b:00007f6e6adfef80 EFLAGS: 00000293 ORIG_RAX: 00000000000000e6 RAX: fffffffffffffdfc RBX: 00007f6e6b1b5fa0 RCX: 00007f6e6afc1225 RDX: 00007f6e6adfefc0 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 00007f6e6b010ab1 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000000 R13: 0000000000000001 R14: 00007f6e6b1b5fa0 R15: 00007ffd05543728 ================================================================== BUG: kernel NULL pointer dereference, address: 0000000000000170 #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: 0 PID: 22148 Comm: syz.4.5870 Tainted: G B W 6.1.134-syzkaller-00014-g3cd01bb5bd37 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/19/2025 RIP: 0010:arch_atomic_add_return arch/x86/include/asm/atomic.h:165 [inline] RIP: 0010:arch_atomic_inc_return include/linux/atomic/atomic-arch-fallback.h:440 [inline] RIP: 0010:atomic_inc_return include/linux/atomic/atomic-instrumented.h:199 [inline] RIP: 0010:ihold+0x26/0x60 fs/inode.c:452 Code: 33 36 7c df 55 48 89 e5 41 56 53 48 89 fb e8 d1 90 ac ff 48 8d bb 70 01 00 00 be 04 00 00 00 e8 b0 e5 f0 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:ffffc9000314f798 EFLAGS: 00010246 RAX: ffff88812492a800 RBX: 0000000000000000 RCX: ffff88812492a880 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: ffffc9000314f7a8 R08: dffffc0000000000 R09: fffffbfff0f2ccfd R10: fffffbfff0f2ccfd R11: 1ffffffff0f2ccfc R12: ffff8881380bedec R13: dffffc0000000000 R14: 0000000000000001 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff8881f7000000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000170 CR3: 0000000006e0f000 CR4: 00000000003526b0 DR0: 0000000010000007 DR1: 400000000000000c DR2: 000000000000000d DR3: 00000000000000ff DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: d_delete_notify include/linux/fsnotify.h:289 [inline] vfs_rmdir+0x25f/0x500 fs/namei.c:4203 incfs_kill_sb+0x105/0x220 fs/incfs/vfs.c:1995 deactivate_locked_super+0xb5/0x120 fs/super.c:334 deactivate_super+0xaf/0xe0 fs/super.c:365 cleanup_mnt+0x45f/0x4e0 fs/namespace.c:1186 __cleanup_mnt+0x19/0x20 fs/namespace.c:1193 task_work_run+0x1db/0x240 kernel/task_work.c:203 exit_task_work include/linux/task_work.h:39 [inline] do_exit+0xa1d/0x2650 kernel/exit.c:877 do_group_exit+0x210/0x2d0 kernel/exit.c:1027 get_signal+0x13b5/0x1520 kernel/signal.c:2889 arch_do_signal_or_restart+0xb0/0x1030 arch/x86/kernel/signal.c:871 exit_to_user_mode_loop+0x7a/0xb0 kernel/entry/common.c:174 exit_to_user_mode_prepare+0x5a/0xa0 kernel/entry/common.c:210 __syscall_exit_to_user_mode_work kernel/entry/common.c:292 [inline] syscall_exit_to_user_mode+0x1a/0x30 kernel/entry/common.c:303 do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:87 entry_SYSCALL_64_after_hwframe+0x68/0xd2 RIP: 0033:0x7f6e6afc1225 Code: Unable to access opcode bytes at 0x7f6e6afc11fb. RSP: 002b:00007f6e6adfef80 EFLAGS: 00000293 ORIG_RAX: 00000000000000e6 RAX: fffffffffffffdfc RBX: 00007f6e6b1b5fa0 RCX: 00007f6e6afc1225 RDX: 00007f6e6adfefc0 RSI: 0000000000000000 RDI: 0000000000000000 RBP: 00007f6e6b010ab1 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000293 R12: 0000000000000000 R13: 0000000000000001 R14: 00007f6e6b1b5fa0 R15: 00007ffd05543728 Modules linked in: CR2: 0000000000000170 ---[ end trace 0000000000000000 ]--- RIP: 0010:arch_atomic_add_return arch/x86/include/asm/atomic.h:165 [inline] RIP: 0010:arch_atomic_inc_return include/linux/atomic/atomic-arch-fallback.h:440 [inline] RIP: 0010:atomic_inc_return include/linux/atomic/atomic-instrumented.h:199 [inline] RIP: 0010:ihold+0x26/0x60 fs/inode.c:452 Code: 33 36 7c df 55 48 89 e5 41 56 53 48 89 fb e8 d1 90 ac ff 48 8d bb 70 01 00 00 be 04 00 00 00 e8 b0 e5 f0 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:ffffc9000314f798 EFLAGS: 00010246 RAX: ffff88812492a800 RBX: 0000000000000000 RCX: ffff88812492a880 RDX: 0000000000000000 RSI: 0000000000000000 RDI: 0000000000000000 RBP: ffffc9000314f7a8 R08: dffffc0000000000 R09: fffffbfff0f2ccfd R10: fffffbfff0f2ccfd R11: 1ffffffff0f2ccfc R12: ffff8881380bedec R13: dffffc0000000000 R14: 0000000000000001 R15: 0000000000000000 FS: 0000000000000000(0000) GS:ffff8881f7000000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 0000000000000170 CR3: 0000000006e0f000 CR4: 00000000003526b0 DR0: 0000000010000007 DR1: 400000000000000c DR2: 000000000000000d DR3: 00000000000000ff DR6: 00000000fffe0ff0 DR7: 0000000000000400 ---------------- Code disassembly (best guess): 0: 33 36 xor (%rsi),%esi 2: 7c df jl 0xffffffe3 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 d1 90 ac ff call 0xffac90e4 13: 48 8d bb 70 01 00 00 lea 0x170(%rbx),%rdi 1a: be 04 00 00 00 mov $0x4,%esi 1f: e8 b0 e5 f0 ff call 0xfff0e5d4 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