syzbot


WARNING: refcount bug in cache_clean

Status: moderation: reported on 2024/05/05 05:53
Subsystems: net nfs
[Documentation on labels]
Reported-by: syzbot+c31346016beea569adba@syzkaller.appspotmail.com
First crash: 45d, last: 45d

Sample crash report:
------------[ cut here ]------------
refcount_t: underflow; use-after-free.
WARNING: CPU: 1 PID: 5179 at lib/refcount.c:28 refcount_warn_saturate+0x15a/0x1d0 lib/refcount.c:28
Modules linked in:
CPU: 1 PID: 5179 Comm: kworker/1:6 Not tainted 6.9.0-rc5-syzkaller-01459-gc2e6a872bde9 #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/27/2024
Workqueue: events_power_efficient do_cache_clean
RIP: 0010:refcount_warn_saturate+0x15a/0x1d0 lib/refcount.c:28
Code: e0 4b 1f 8c e8 07 fe a8 fc 90 0f 0b 90 90 eb 99 e8 7b 81 e6 fc c6 05 3d 3e e4 0a 01 90 48 c7 c7 40 4c 1f 8c e8 e7 fd a8 fc 90 <0f> 0b 90 90 e9 76 ff ff ff e8 58 81 e6 fc c6 05 17 3e e4 0a 01 90
RSP: 0018:ffffc900039afa68 EFLAGS: 00010246
RAX: 238e75778706bd00 RBX: ffff88807dd63958 RCX: ffff8880219e1e00
RDX: 0000000000000000 RSI: 0000000000000001 RDI: 0000000000000000
RBP: 0000000000000003 R08: ffffffff81589b62 R09: fffffbfff1c39b6c
R10: dffffc0000000000 R11: fffffbfff1c39b6c R12: 0000000000000000
R13: dffffc0000000000 R14: ffffffff8a967a40 R15: ffff88807dd63958
FS:  0000000000000000(0000) GS:ffff8880b9500000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 0000000020011038 CR3: 00000000234c2000 CR4: 00000000003506f0
DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000
DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400
Call Trace:
 <TASK>
 __refcount_sub_and_test include/linux/refcount.h:275 [inline]
 __refcount_dec_and_test include/linux/refcount.h:307 [inline]
 refcount_dec_and_test include/linux/refcount.h:325 [inline]
 kref_put include/linux/kref.h:64 [inline]
 cache_put include/linux/sunrpc/cache.h:213 [inline]
 sunrpc_end_cache_remove_entry net/sunrpc/cache.c:96 [inline]
 cache_clean+0x9de/0xa30 net/sunrpc/cache.c:491
 do_cache_clean+0x22/0xb0 net/sunrpc/cache.c:508
 process_one_work kernel/workqueue.c:3254 [inline]
 process_scheduled_works+0xa10/0x17c0 kernel/workqueue.c:3335
 worker_thread+0x86d/0xd70 kernel/workqueue.c:3416
 kthread+0x2f0/0x390 kernel/kthread.c:388
 ret_from_fork+0x4b/0x80 arch/x86/kernel/process.c:147
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:244
 </TASK>

Crashes (2):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2024/05/01 05:50 net-next c2e6a872bde9 9e0e6af1 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-net-kasan-gce WARNING: refcount bug in cache_clean
2024/05/01 12:07 linux-next f68868ba718e 3ba885bc .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-linux-next-kasan-gce-root WARNING: refcount bug in cache_clean
* Struck through repros no longer work on HEAD.