KASAN: null-ptr-deref Write in fput

ID	Workflow	Result	Correct	Bug	Created	Started	Finished	Revision
f22404c7	assessment-security	DenialOfService: ✅ Exploitable: ✅ FilesystemTrigger: ❌ NetworkTrigger: ❌ PeripheralTrigger: ❌ RemoteTrigger: ❌ Unprivileged: ❌ UserNamespace: ❌ VMGuestTrigger: ❌ VMHostTrigger: ❌	❓	KASAN: null-ptr-deref Write in fput	2026/08/09 08:16	2026/08/09 08:16	2026/08/09 08:58	5d63f80b

Title	Replies (including bot)	Last reply
[syzbot] [ocfs2?] KASAN: null-ptr-deref Write in fput	0 (1)	2026/08/08 19:56

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[syzbot] [ocfs2?] KASAN: null-ptr-deref Write in fput

0 (1)

2026/08/08 19:56

Created	Duration	User	Patch	Repo	Result
2026/08/19 09:37	20m	retest repro		upstream	report job log log

Created

Duration

User

Patch

Repo

Result

2026/08/19 09:37

20m

retest repro

upstream

report job log log

(syz-executor157,5664,1):o2hb_bio_end_io:499 ERROR: IO Error 10 (syz-executor157,5664,1):o2hb_region_dev_store:1850 ERROR: status = -5 ================================================================== BUG: KASAN: null-ptr-deref in instrument_atomic_read_write include/linux/instrumented.h:112 [inline] BUG: KASAN: null-ptr-deref in atomic_long_dec_return include/linux/atomic/atomic-instrumented.h:3766 [inline] BUG: KASAN: null-ptr-deref in file_ref_put include/linux/file_ref.h:157 [inline] BUG: KASAN: null-ptr-deref in fput+0x2e/0x100 fs/file_table.c:588 Write of size 8 at addr 0000000000000158 by task syz-executor157/5664 CPU: 1 UID: 0 PID: 5664 Comm: syz-executor157 Not tainted syzkaller #0 PREEMPT(full) Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/16/2026 Call Trace: <TASK> __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x100/0x190 lib/dump_stack.c:120 kasan_report+0xdf/0x1c0 mm/kasan/report.c:595 check_region_inline mm/kasan/generic.c:186 [inline] kasan_check_range+0x10f/0x1e0 mm/kasan/generic.c:200 instrument_atomic_read_write include/linux/instrumented.h:112 [inline] atomic_long_dec_return include/linux/atomic/atomic-instrumented.h:3766 [inline] file_ref_put include/linux/file_ref.h:157 [inline] fput+0x2e/0x100 fs/file_table.c:588 o2hb_region_dev_store+0x1230/0x1bc0 fs/ocfs2/cluster/heartbeat.c:1935 flush_write_buffer fs/configfs/file.c:207 [inline] configfs_write_iter+0x302/0x4e0 fs/configfs/file.c:229 new_sync_write fs/read_write.c:595 [inline] vfs_write+0x6ac/0x1050 fs/read_write.c:687 ksys_write+0x12a/0x250 fs/read_write.c:739 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x115/0x870 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7fd8eccb5ab9 Code: c0 79 93 eb d5 48 8d 7c 1d 00 eb 99 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 d8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007ffc7d881e78 EFLAGS: 00000246 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 0000200000000540 RCX: 00007fd8eccb5ab9 RDX: 0000000000000001 RSI: 00002000000005c0 RDI: 0000000000000004 RBP: 0030706f6f6c2f2e R08: 0000000000000009 R09: 0000000000000009 R10: 0000000000000009 R11: 0000000000000246 R12: 000000000001009b R13: 00007ffc7d881e8c R14: 00007ffc7d881ea0 R15: 0000200000000008 </TASK> ==================================================================

Crashes (3):
Time	Kernel	Commit	Syzkaller	Config	Log	Report	Syz repro	C repro	VM info	Assets (help?)	Manager	Title
2026/08/05 00:44	upstream	848acc8ffe1b	d4abbeac	.config	strace log	report	syz / log	C		[disk image] [vmlinux] [kernel image]	ci-upstream-kasan-gce-selinux-root	KASAN: null-ptr-deref Write in fput
2026/08/04 16:29	upstream	848acc8ffe1b	d4abbeac	.config	console log	report			info	[disk image] [vmlinux] [kernel image]	ci-upstream-kasan-gce-selinux-root	KASAN: null-ptr-deref Write in fput
2026/08/04 16:29	upstream	848acc8ffe1b	d4abbeac	.config	console log	report			info	[disk image] [vmlinux] [kernel image]	ci-upstream-kasan-gce-selinux-root	KASAN: null-ptr-deref Write in fput

Crashes (3):

Assets (help?)