Extracting prog: 1m25.38666179s
Minimizing prog: 6m35.724997682s
Simplifying prog options: 0s
Extracting C: 22.551335072s
Simplifying C: 14m44.087768277s
extracting reproducer from 1 programs
testing a last program of every proc
single: executing 1 programs separately with timeout 30s
testing program (duration=30s, {Threaded:true Repeat:true RepeatTimes:0 Procs:5 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:false Wifi:false IEEE802154:false Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): mkdir-mount$incfs
detailed listing:
executing program 0:
mkdir(&(0x7f00000000c0)='./bus\x00', 0x0)
mount$incfs(&(0x7f00000007c0)='.\x00', &(0x7f0000000800)='./bus\x00', &(0x7f0000000840), 0x1004002, 0x0)
program crashed: KASAN: null-ptr-deref Write in vfs_rmdir
single: successfully extracted reproducer
found reproducer with 2 syscalls
minimizing guilty program
testing program (duration=35.215562041s, {Threaded:true Repeat:true RepeatTimes:0 Procs:5 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:false Wifi:false IEEE802154:false Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): mkdir
detailed listing:
executing program 0:
mkdir(&(0x7f00000000c0)='./bus\x00', 0x0)
program did not crash
testing program (duration=35.215562041s, {Threaded:true Repeat:true RepeatTimes:0 Procs:5 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:false Wifi:false IEEE802154:false Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): mount$incfs
detailed listing:
executing program 0:
mount$incfs(&(0x7f00000007c0)='.\x00', &(0x7f0000000800)='./bus\x00', &(0x7f0000000840), 0x1004002, 0x0)
program did not crash
testing program (duration=35.215562041s, {Threaded:true Repeat:true RepeatTimes:0 Procs:5 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:false Wifi:false IEEE802154:false Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): mkdir-mount$incfs
detailed listing:
executing program 0:
mkdir(0x0, 0x0)
mount$incfs(&(0x7f00000007c0)='.\x00', &(0x7f0000000800)='./bus\x00', &(0x7f0000000840), 0x1004002, 0x0)
program did not crash
testing program (duration=35.215562041s, {Threaded:true Repeat:true RepeatTimes:0 Procs:5 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:false Wifi:false IEEE802154:false Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): mkdir-mount$incfs
detailed listing:
executing program 0:
mkdir(&(0x7f00000000c0)='./bus\x00', 0x0)
mount$incfs(0x0, &(0x7f0000000800)='./bus\x00', &(0x7f0000000840), 0x1004002, 0x0)
program did not crash
testing program (duration=35.215562041s, {Threaded:true Repeat:true RepeatTimes:0 Procs:5 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:false Wifi:false IEEE802154:false Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): mkdir-mount$incfs
detailed listing:
executing program 0:
mkdir(&(0x7f00000000c0)='./bus\x00', 0x0)
mount$incfs(&(0x7f00000007c0)='.\x00', 0x0, &(0x7f0000000840), 0x1004002, 0x0)
program did not crash
testing program (duration=35.215562041s, {Threaded:true Repeat:true RepeatTimes:0 Procs:5 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:false Wifi:false IEEE802154:false Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): mkdir-mount$incfs
detailed listing:
executing program 0:
mkdir(&(0x7f00000000c0)='./bus\x00', 0x0)
mount$incfs(&(0x7f00000007c0)='.\x00', &(0x7f0000000800)='./bus\x00', 0x0, 0x1004002, 0x0)
program did not crash
extracting C reproducer
testing compiled C program (duration=35.215562041s, {Threaded:true Repeat:true RepeatTimes:0 Procs:5 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:false Wifi:false IEEE802154:false Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): mkdir-mount$incfs
program crashed: KASAN: null-ptr-deref Write in vfs_rmdir
simplifying C reproducer
testing compiled C program (duration=35.215562041s, {Threaded:false Repeat:true RepeatTimes:0 Procs:5 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:false Wifi:false IEEE802154:false Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): mkdir-mount$incfs
program crashed: KASAN: null-ptr-deref Write in vfs_rmdir
testing compiled C program (duration=35.215562041s, {Threaded:false Repeat:false RepeatTimes:0 Procs:1 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:false Cgroups:false BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:false Wifi:false IEEE802154:false Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): mkdir-mount$incfs
program did not crash
testing compiled C program (duration=35.215562041s, {Threaded:false Repeat:true RepeatTimes:0 Procs:1 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:true NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:false Wifi:false IEEE802154:false Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): mkdir-mount$incfs
program crashed: KASAN: null-ptr-deref Write in vfs_rmdir
testing compiled C program (duration=35.215562041s, {Threaded:false Repeat:true RepeatTimes:0 Procs:1 Slowdown:1 Sandbox: SandboxArg:0 Leak:false NetInjection:false NetDevices:false NetReset:false Cgroups:false BinfmtMisc:false CloseFDs:false KCSAN:false DevlinkPCI:false NicVF:false USB:false VhciInjection:false Wifi:false IEEE802154:false Sysctl:true Swap:false UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): mkdir-mount$incfs
program did not crash
testing compiled C program (duration=35.215562041s, {Threaded:false Repeat:true RepeatTimes:0 Procs:1 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:false NetDevices:true NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:false Wifi:false IEEE802154:false Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): mkdir-mount$incfs
program crashed: KASAN: null-ptr-deref Write in vfs_rmdir
testing compiled C program (duration=35.215562041s, {Threaded:false Repeat:true RepeatTimes:0 Procs:1 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:false NetDevices:false NetReset:true Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:false Wifi:false IEEE802154:false Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): mkdir-mount$incfs
program crashed: KASAN: null-ptr-deref Write in vfs_rmdir
testing compiled C program (duration=35.215562041s, {Threaded:false Repeat:true RepeatTimes:0 Procs:1 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:false NetDevices:false NetReset:false Cgroups:true BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:false Wifi:false IEEE802154:false Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): mkdir-mount$incfs
program crashed: KASAN: null-ptr-deref Write in vfs_rmdir
testing compiled C program (duration=35.215562041s, {Threaded:false Repeat:true RepeatTimes:0 Procs:1 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:false NetDevices:false NetReset:false Cgroups:false BinfmtMisc:true CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:false Wifi:false IEEE802154:false Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): mkdir-mount$incfs
program crashed: KASAN: null-ptr-deref Write in vfs_rmdir
testing compiled C program (duration=35.215562041s, {Threaded:false Repeat:true RepeatTimes:0 Procs:1 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:false NetDevices:false NetReset:false Cgroups:false BinfmtMisc:false CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:true VhciInjection:false Wifi:false IEEE802154:false Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): mkdir-mount$incfs
program crashed: KASAN: null-ptr-deref Write in vfs_rmdir
testing compiled C program (duration=35.215562041s, {Threaded:false Repeat:true RepeatTimes:0 Procs:1 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:false NetDevices:false NetReset:false Cgroups:false BinfmtMisc:false CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:false VhciInjection:false Wifi:false IEEE802154:false Sysctl:true Swap:true UseTmpDir:true HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): mkdir-mount$incfs
program crashed: KASAN: null-ptr-deref Write in vfs_rmdir
testing compiled C program (duration=35.215562041s, {Threaded:false Repeat:true RepeatTimes:0 Procs:1 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:false NetDevices:false NetReset:false Cgroups:false BinfmtMisc:false CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:false VhciInjection:false Wifi:false IEEE802154:false Sysctl:true Swap:true UseTmpDir:false HandleSegv:true Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): mkdir-mount$incfs
program did not crash
testing compiled C program (duration=35.215562041s, {Threaded:false Repeat:true RepeatTimes:0 Procs:1 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:false NetDevices:false NetReset:false Cgroups:false BinfmtMisc:false CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:false VhciInjection:false Wifi:false IEEE802154:false Sysctl:true Swap:true UseTmpDir:true HandleSegv:false Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): mkdir-mount$incfs
program crashed: KASAN: null-ptr-deref Write in vfs_rmdir
testing compiled C program (duration=35.215562041s, {Threaded:false Repeat:true RepeatTimes:0 Procs:1 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:false NetDevices:false NetReset:false Cgroups:false BinfmtMisc:false CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:false VhciInjection:false Wifi:false IEEE802154:false Sysctl:false Swap:true UseTmpDir:true HandleSegv:false Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): mkdir-mount$incfs
program crashed: KASAN: null-ptr-deref Write in vfs_rmdir
testing compiled C program (duration=35.215562041s, {Threaded:false Repeat:true RepeatTimes:0 Procs:1 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:false NetDevices:false NetReset:false Cgroups:false BinfmtMisc:false CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:false VhciInjection:false Wifi:false IEEE802154:false Sysctl:false Swap:false UseTmpDir:true HandleSegv:false Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): mkdir-mount$incfs
program crashed: KASAN: null-ptr-deref Write in vfs_rmdir
testing program (duration=35.215562041s, {Threaded:false Repeat:true RepeatTimes:0 Procs:1 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:false NetDevices:false NetReset:false Cgroups:false BinfmtMisc:false CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:false VhciInjection:false Wifi:false IEEE802154:false Sysctl:false Swap:false UseTmpDir:true HandleSegv:false Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): mkdir-mount$incfs
detailed listing:
executing program 0:
mkdir(&(0x7f00000000c0)='./bus\x00', 0x0)
mount$incfs(&(0x7f00000007c0)='.\x00', &(0x7f0000000800)='./bus\x00', &(0x7f0000000840), 0x1004002, 0x0)
program crashed: KASAN: null-ptr-deref Write in vfs_rmdir
validation run: crashed=true
testing program (duration=35.215562041s, {Threaded:false Repeat:true RepeatTimes:0 Procs:1 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:false NetDevices:false NetReset:false Cgroups:false BinfmtMisc:false CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:false VhciInjection:false Wifi:false IEEE802154:false Sysctl:false Swap:false UseTmpDir:true HandleSegv:false Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): mkdir-mount$incfs
detailed listing:
executing program 0:
mkdir(&(0x7f00000000c0)='./bus\x00', 0x0)
mount$incfs(&(0x7f00000007c0)='.\x00', &(0x7f0000000800)='./bus\x00', &(0x7f0000000840), 0x1004002, 0x0)
program crashed: KASAN: null-ptr-deref Write in vfs_rmdir
validation run: crashed=true
testing program (duration=35.215562041s, {Threaded:false Repeat:true RepeatTimes:0 Procs:1 Slowdown:1 Sandbox:none SandboxArg:0 Leak:false NetInjection:false NetDevices:false NetReset:false Cgroups:false BinfmtMisc:false CloseFDs:true KCSAN:false DevlinkPCI:false NicVF:false USB:false VhciInjection:false Wifi:false IEEE802154:false Sysctl:false Swap:false UseTmpDir:true HandleSegv:false Trace:false CallComments:true LegacyOptions:{Collide:false Fault:false FaultCall:0 FaultNth:0}}): mkdir-mount$incfs
detailed listing:
executing program 0:
mkdir(&(0x7f00000000c0)='./bus\x00', 0x0)
mount$incfs(&(0x7f00000007c0)='.\x00', &(0x7f0000000800)='./bus\x00', &(0x7f0000000840), 0x1004002, 0x0)
program crashed: KASAN: null-ptr-deref Write in vfs_rmdir
validation run: crashed=true
reproducing took 25m41.848805597s
repro crashed as (corrupted=false):
Code: a2 c7 05 9c fc 24 00 00 00 00 00 eb 96 e8 e1 12 00 00 90 31 f6 e9 09 00 00 00 66 0f 1f 84 00 00 00 00 00 b8 a6 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 01 c3 48 c7 c2 e8 ff ff ff f7 d8 64 89 02 b8
RSP: 002b:00007ffe3bcb63b8 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 00007fdba0caaa57
RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007ffe3bcb6470
RBP: 00007ffe3bcb6470 R08: 00007ffe3bcb7470 R09: 00000000ffffffff
R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffe3bcb7500
R13: 00007fdba0d3f048 R14: 0000000000005fa1 R15: 00007ffe3bcb7540
---[ end trace 3dfa70613eb57b6c ]---
==================================================================
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/linux/atomic/atomic-instrumented.h:188 [inline]
BUG: KASAN: null-ptr-deref in ihold+0x20/0x60 fs/inode.c:454
Write of size 4 at addr 0000000000000170 by task syz-executor/355
CPU: 0 PID: 355 Comm: syz-executor Tainted: G W syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026
Call Trace:
__dump_stack+0x21/0x30 lib/dump_stack.c:88
dump_stack_lvl+0x110/0x170 lib/dump_stack.c:106
__kasan_report mm/kasan/report.c:431 [inline]
kasan_report+0xe7/0x140 mm/kasan/report.c:444
check_region_inline mm/kasan/generic.c:-1 [inline]
kasan_check_range+0x249/0x2a0 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/linux/atomic/atomic-instrumented.h:188 [inline]
ihold+0x20/0x60 fs/inode.c:454
d_delete_notify include/linux/fsnotify.h:275 [inline]
vfs_rmdir+0x1f0/0x460 fs/namei.c:4170
incfs_kill_sb+0x105/0x220 fs/incfs/vfs.c:1989
deactivate_locked_super+0xa0/0x100 fs/super.c:335
deactivate_super+0xaf/0xe0 fs/super.c:366
cleanup_mnt+0x45b/0x510 fs/namespace.c:1148
__cleanup_mnt+0x19/0x20 fs/namespace.c:1155
task_work_run+0x127/0x190 kernel/task_work.c:188
tracehook_notify_resume include/linux/tracehook.h:189 [inline]
exit_to_user_mode_loop+0xd0/0xe0 kernel/entry/common.c:181
exit_to_user_mode_prepare+0x87/0xd0 kernel/entry/common.c:214
__syscall_exit_to_user_mode_work kernel/entry/common.c:296 [inline]
syscall_exit_to_user_mode+0x1a/0x30 kernel/entry/common.c:307
do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:86
entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7fdba0caaa57
Code: a2 c7 05 9c fc 24 00 00 00 00 00 eb 96 e8 e1 12 00 00 90 31 f6 e9 09 00 00 00 66 0f 1f 84 00 00 00 00 00 b8 a6 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 01 c3 48 c7 c2 e8 ff ff ff f7 d8 64 89 02 b8
RSP: 002b:00007ffe3bcb63b8 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 00007fdba0caaa57
RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007ffe3bcb6470
RBP: 00007ffe3bcb6470 R08: 00007ffe3bcb7470 R09: 00000000ffffffff
R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffe3bcb7500
R13: 00007fdba0d3f048 R14: 0000000000005fa1 R15: 00007ffe3bcb7540
==================================================================
BUG: kernel NULL pointer dereference, address: 0000000000000170
#PF: supervisor write access in kernel mode
#PF: error_code(0x0002) - not-present page
PGD 11d8ca067 P4D 11d8ca067 PUD 0
Oops: 0002 [#1] PREEMPT SMP KASAN
CPU: 0 PID: 355 Comm: syz-executor Tainted: G B W syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026
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:370 [inline]
RIP: 0010:atomic_inc_return include/linux/atomic/atomic-instrumented.h:189 [inline]
RIP: 0010:ihold+0x26/0x60 fs/inode.c:454
Code: 00 00 00 00 55 48 89 e5 41 56 53 48 89 fb e8 f1 ca b2 ff 48 8d bb 70 01 00 00 be 04 00 00 00 e8 90 fb f1 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 71
RSP: 0018:ffffc90000ad7ce8 EFLAGS: 00010246
RAX: ffff88810c633b00 RBX: 0000000000000000 RCX: ffff88810c633b40
RDX: 0000000000000000 RSI: 0000000000000002 RDI: 00000000ffffffff
RBP: ffffc90000ad7cf8 R08: 0000000000000003 R09: 0000000000000004
R10: dffffc0000000000 R11: fffffbfff0e18a4c R12: 1ffff11021a11ef4
R13: dffffc0000000000 R14: 0000000000000001 R15: 0000000000000000
FS: 0000555591898500(0000) GS:ffff8881f7000000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000170 CR3: 000000010ddcc000 CR4: 00000000003506b0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
d_delete_notify include/linux/fsnotify.h:275 [inline]
vfs_rmdir+0x1f0/0x460 fs/namei.c:4170
incfs_kill_sb+0x105/0x220 fs/incfs/vfs.c:1989
deactivate_locked_super+0xa0/0x100 fs/super.c:335
deactivate_super+0xaf/0xe0 fs/super.c:366
cleanup_mnt+0x45b/0x510 fs/namespace.c:1148
__cleanup_mnt+0x19/0x20 fs/namespace.c:1155
task_work_run+0x127/0x190 kernel/task_work.c:188
tracehook_notify_resume include/linux/tracehook.h:189 [inline]
exit_to_user_mode_loop+0xd0/0xe0 kernel/entry/common.c:181
exit_to_user_mode_prepare+0x87/0xd0 kernel/entry/common.c:214
__syscall_exit_to_user_mode_work kernel/entry/common.c:296 [inline]
syscall_exit_to_user_mode+0x1a/0x30 kernel/entry/common.c:307
do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:86
entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7fdba0caaa57
Code: a2 c7 05 9c fc 24 00 00 00 00 00 eb 96 e8 e1 12 00 00 90 31 f6 e9 09 00 00 00 66 0f 1f 84 00 00 00 00 00 b8 a6 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 01 c3 48 c7 c2 e8 ff ff ff f7 d8 64 89 02 b8
RSP: 002b:00007ffe3bcb63b8 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 00007fdba0caaa57
RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007ffe3bcb6470
RBP: 00007ffe3bcb6470 R08: 00007ffe3bcb7470 R09: 00000000ffffffff
R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffe3bcb7500
R13: 00007fdba0d3f048 R14: 0000000000005fa1 R15: 00007ffe3bcb7540
Modules linked in:
CR2: 0000000000000170
---[ end trace 3dfa70613eb57b6d ]---
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:370 [inline]
RIP: 0010:atomic_inc_return include/linux/atomic/atomic-instrumented.h:189 [inline]
RIP: 0010:ihold+0x26/0x60 fs/inode.c:454
Code: 00 00 00 00 55 48 89 e5 41 56 53 48 89 fb e8 f1 ca b2 ff 48 8d bb 70 01 00 00 be 04 00 00 00 e8 90 fb f1 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 71
RSP: 0018:ffffc90000ad7ce8 EFLAGS: 00010246
RAX: ffff88810c633b00 RBX: 0000000000000000 RCX: ffff88810c633b40
RDX: 0000000000000000 RSI: 0000000000000002 RDI: 00000000ffffffff
RBP: ffffc90000ad7cf8 R08: 0000000000000003 R09: 0000000000000004
R10: dffffc0000000000 R11: fffffbfff0e18a4c R12: 1ffff11021a11ef4
R13: dffffc0000000000 R14: 0000000000000001 R15: 0000000000000000
FS: 0000555591898500(0000) GS:ffff8881f7000000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000170 CR3: 000000010ddcc000 CR4: 00000000003506b0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
----------------
Code disassembly (best guess):
0: a2 c7 05 9c fc 24 00 movabs %al,0x24fc9c05c7
7: 00 00
9: 00 00 add %al,(%rax)
b: eb 96 jmp 0xffffffa3
d: e8 e1 12 00 00 call 0x12f3
12: 90 nop
13: 31 f6 xor %esi,%esi
15: e9 09 00 00 00 jmp 0x23
1a: 66 0f 1f 84 00 00 00 nopw 0x0(%rax,%rax,1)
21: 00 00
23: b8 a6 00 00 00 mov $0xa6,%eax
28: 0f 05 syscall
* 2a: 48 3d 00 f0 ff ff cmp $0xfffffffffffff000,%rax <-- trapping instruction
30: 77 01 ja 0x33
32: c3 ret
33: 48 c7 c2 e8 ff ff ff mov $0xffffffffffffffe8,%rdx
3a: f7 d8 neg %eax
3c: 64 89 02 mov %eax,%fs:(%rdx)
3f: b8 .byte 0xb8
final repro crashed as (corrupted=false):
Code: a2 c7 05 9c fc 24 00 00 00 00 00 eb 96 e8 e1 12 00 00 90 31 f6 e9 09 00 00 00 66 0f 1f 84 00 00 00 00 00 b8 a6 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 01 c3 48 c7 c2 e8 ff ff ff f7 d8 64 89 02 b8
RSP: 002b:00007ffe3bcb63b8 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 00007fdba0caaa57
RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007ffe3bcb6470
RBP: 00007ffe3bcb6470 R08: 00007ffe3bcb7470 R09: 00000000ffffffff
R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffe3bcb7500
R13: 00007fdba0d3f048 R14: 0000000000005fa1 R15: 00007ffe3bcb7540
---[ end trace 3dfa70613eb57b6c ]---
==================================================================
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/linux/atomic/atomic-instrumented.h:188 [inline]
BUG: KASAN: null-ptr-deref in ihold+0x20/0x60 fs/inode.c:454
Write of size 4 at addr 0000000000000170 by task syz-executor/355
CPU: 0 PID: 355 Comm: syz-executor Tainted: G W syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026
Call Trace:
__dump_stack+0x21/0x30 lib/dump_stack.c:88
dump_stack_lvl+0x110/0x170 lib/dump_stack.c:106
__kasan_report mm/kasan/report.c:431 [inline]
kasan_report+0xe7/0x140 mm/kasan/report.c:444
check_region_inline mm/kasan/generic.c:-1 [inline]
kasan_check_range+0x249/0x2a0 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/linux/atomic/atomic-instrumented.h:188 [inline]
ihold+0x20/0x60 fs/inode.c:454
d_delete_notify include/linux/fsnotify.h:275 [inline]
vfs_rmdir+0x1f0/0x460 fs/namei.c:4170
incfs_kill_sb+0x105/0x220 fs/incfs/vfs.c:1989
deactivate_locked_super+0xa0/0x100 fs/super.c:335
deactivate_super+0xaf/0xe0 fs/super.c:366
cleanup_mnt+0x45b/0x510 fs/namespace.c:1148
__cleanup_mnt+0x19/0x20 fs/namespace.c:1155
task_work_run+0x127/0x190 kernel/task_work.c:188
tracehook_notify_resume include/linux/tracehook.h:189 [inline]
exit_to_user_mode_loop+0xd0/0xe0 kernel/entry/common.c:181
exit_to_user_mode_prepare+0x87/0xd0 kernel/entry/common.c:214
__syscall_exit_to_user_mode_work kernel/entry/common.c:296 [inline]
syscall_exit_to_user_mode+0x1a/0x30 kernel/entry/common.c:307
do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:86
entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7fdba0caaa57
Code: a2 c7 05 9c fc 24 00 00 00 00 00 eb 96 e8 e1 12 00 00 90 31 f6 e9 09 00 00 00 66 0f 1f 84 00 00 00 00 00 b8 a6 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 01 c3 48 c7 c2 e8 ff ff ff f7 d8 64 89 02 b8
RSP: 002b:00007ffe3bcb63b8 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 00007fdba0caaa57
RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007ffe3bcb6470
RBP: 00007ffe3bcb6470 R08: 00007ffe3bcb7470 R09: 00000000ffffffff
R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffe3bcb7500
R13: 00007fdba0d3f048 R14: 0000000000005fa1 R15: 00007ffe3bcb7540
==================================================================
BUG: kernel NULL pointer dereference, address: 0000000000000170
#PF: supervisor write access in kernel mode
#PF: error_code(0x0002) - not-present page
PGD 11d8ca067 P4D 11d8ca067 PUD 0
Oops: 0002 [#1] PREEMPT SMP KASAN
CPU: 0 PID: 355 Comm: syz-executor Tainted: G B W syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026
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:370 [inline]
RIP: 0010:atomic_inc_return include/linux/atomic/atomic-instrumented.h:189 [inline]
RIP: 0010:ihold+0x26/0x60 fs/inode.c:454
Code: 00 00 00 00 55 48 89 e5 41 56 53 48 89 fb e8 f1 ca b2 ff 48 8d bb 70 01 00 00 be 04 00 00 00 e8 90 fb f1 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 71
RSP: 0018:ffffc90000ad7ce8 EFLAGS: 00010246
RAX: ffff88810c633b00 RBX: 0000000000000000 RCX: ffff88810c633b40
RDX: 0000000000000000 RSI: 0000000000000002 RDI: 00000000ffffffff
RBP: ffffc90000ad7cf8 R08: 0000000000000003 R09: 0000000000000004
R10: dffffc0000000000 R11: fffffbfff0e18a4c R12: 1ffff11021a11ef4
R13: dffffc0000000000 R14: 0000000000000001 R15: 0000000000000000
FS: 0000555591898500(0000) GS:ffff8881f7000000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000170 CR3: 000000010ddcc000 CR4: 00000000003506b0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
d_delete_notify include/linux/fsnotify.h:275 [inline]
vfs_rmdir+0x1f0/0x460 fs/namei.c:4170
incfs_kill_sb+0x105/0x220 fs/incfs/vfs.c:1989
deactivate_locked_super+0xa0/0x100 fs/super.c:335
deactivate_super+0xaf/0xe0 fs/super.c:366
cleanup_mnt+0x45b/0x510 fs/namespace.c:1148
__cleanup_mnt+0x19/0x20 fs/namespace.c:1155
task_work_run+0x127/0x190 kernel/task_work.c:188
tracehook_notify_resume include/linux/tracehook.h:189 [inline]
exit_to_user_mode_loop+0xd0/0xe0 kernel/entry/common.c:181
exit_to_user_mode_prepare+0x87/0xd0 kernel/entry/common.c:214
__syscall_exit_to_user_mode_work kernel/entry/common.c:296 [inline]
syscall_exit_to_user_mode+0x1a/0x30 kernel/entry/common.c:307
do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:86
entry_SYSCALL_64_after_hwframe+0x66/0xd0
RIP: 0033:0x7fdba0caaa57
Code: a2 c7 05 9c fc 24 00 00 00 00 00 eb 96 e8 e1 12 00 00 90 31 f6 e9 09 00 00 00 66 0f 1f 84 00 00 00 00 00 b8 a6 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 01 c3 48 c7 c2 e8 ff ff ff f7 d8 64 89 02 b8
RSP: 002b:00007ffe3bcb63b8 EFLAGS: 00000246 ORIG_RAX: 00000000000000a6
RAX: 0000000000000000 RBX: 0000000000000000 RCX: 00007fdba0caaa57
RDX: 0000000000000000 RSI: 0000000000000009 RDI: 00007ffe3bcb6470
RBP: 00007ffe3bcb6470 R08: 00007ffe3bcb7470 R09: 00000000ffffffff
R10: 0000000000000000 R11: 0000000000000246 R12: 00007ffe3bcb7500
R13: 00007fdba0d3f048 R14: 0000000000005fa1 R15: 00007ffe3bcb7540
Modules linked in:
CR2: 0000000000000170
---[ end trace 3dfa70613eb57b6d ]---
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:370 [inline]
RIP: 0010:atomic_inc_return include/linux/atomic/atomic-instrumented.h:189 [inline]
RIP: 0010:ihold+0x26/0x60 fs/inode.c:454
Code: 00 00 00 00 55 48 89 e5 41 56 53 48 89 fb e8 f1 ca b2 ff 48 8d bb 70 01 00 00 be 04 00 00 00 e8 90 fb f1 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 71
RSP: 0018:ffffc90000ad7ce8 EFLAGS: 00010246
RAX: ffff88810c633b00 RBX: 0000000000000000 RCX: ffff88810c633b40
RDX: 0000000000000000 RSI: 0000000000000002 RDI: 00000000ffffffff
RBP: ffffc90000ad7cf8 R08: 0000000000000003 R09: 0000000000000004
R10: dffffc0000000000 R11: fffffbfff0e18a4c R12: 1ffff11021a11ef4
R13: dffffc0000000000 R14: 0000000000000001 R15: 0000000000000000
FS: 0000555591898500(0000) GS:ffff8881f7000000(0000) knlGS:0000000000000000
CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000000000170 CR3: 000000010ddcc000 CR4: 00000000003506b0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
----------------
Code disassembly (best guess):
0: a2 c7 05 9c fc 24 00 movabs %al,0x24fc9c05c7
7: 00 00
9: 00 00 add %al,(%rax)
b: eb 96 jmp 0xffffffa3
d: e8 e1 12 00 00 call 0x12f3
12: 90 nop
13: 31 f6 xor %esi,%esi
15: e9 09 00 00 00 jmp 0x23
1a: 66 0f 1f 84 00 00 00 nopw 0x0(%rax,%rax,1)
21: 00 00
23: b8 a6 00 00 00 mov $0xa6,%eax
28: 0f 05 syscall
* 2a: 48 3d 00 f0 ff ff cmp $0xfffffffffffff000,%rax <-- trapping instruction
30: 77 01 ja 0x33
32: c3 ret
33: 48 c7 c2 e8 ff ff ff mov $0xffffffffffffffe8,%rdx
3a: f7 d8 neg %eax
3c: 64 89 02 mov %eax,%fs:(%rdx)
3f: b8 .byte 0xb8