syzbot


general protection fault in rtlock_slowlock_locked

Status: upstream: reported syz repro on 2025/10/02 16:01
Subsystems: block
[Documentation on labels]
Reported-by: syzbot+08df3e4c9b304b37cb04@syzkaller.appspotmail.com
First crash: 99d, last: 8d18h
Discussions (1)
Title Replies (including bot) Last reply
[syzbot] [ntfs3?] [usb?] general protection fault in rtlock_slowlock_locked 6 (14) 2025/11/11 00:12
Last patch testing requests (6)
Created Duration User Patch Repo Result
2025/11/10 23:21 50m eadavis@qq.com patch upstream report log
2025/11/10 14:51 17m eadavis@qq.com patch upstream report log
2025/11/10 14:18 19m eadavis@qq.com patch upstream report log
2025/11/10 13:09 16m eadavis@qq.com patch upstream report log
2025/11/10 12:13 17m eadavis@qq.com patch upstream report log
2025/11/08 07:43 20m hdanton@sina.com patch upstream OK log

Sample crash report:
==================================================================
BUG: KASAN: slab-use-after-free in __raw_spin_lock_irq include/linux/spinlock_api_smp.h:119 [inline]
BUG: KASAN: slab-use-after-free in _raw_spin_lock_irq+0xa2/0xf0 kernel/locking/spinlock.c:170
Read of size 1 at addr ffff888030dcba68 by task ksoftirqd/1/30

CPU: 1 UID: 0 PID: 30 Comm: ksoftirqd/1 Not tainted syzkaller #0 PREEMPT_{RT,(full)} 
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/02/2025
Call Trace:
 <TASK>
 dump_stack_lvl+0x189/0x250 lib/dump_stack.c:120
 print_address_description mm/kasan/report.c:378 [inline]
 print_report+0xca/0x240 mm/kasan/report.c:482
 kasan_report+0x118/0x150 mm/kasan/report.c:595
 __kasan_check_byte+0x2a/0x40 mm/kasan/common.c:580
 kasan_check_byte include/linux/kasan.h:401 [inline]
 lock_acquire+0x8d/0x360 kernel/locking/lockdep.c:5842
 __raw_spin_lock_irq include/linux/spinlock_api_smp.h:119 [inline]
 _raw_spin_lock_irq+0xa2/0xf0 kernel/locking/spinlock.c:170
 rtlock_slowlock_locked+0x3821/0x4010 kernel/locking/rtmutex.c:1871
 rtlock_slowlock kernel/locking/rtmutex.c:1895 [inline]
 rtlock_lock kernel/locking/spinlock_rt.c:43 [inline]
 __rt_spin_lock kernel/locking/spinlock_rt.c:49 [inline]
 rt_spin_lock+0x158/0x3e0 kernel/locking/spinlock_rt.c:57
 spin_lock include/linux/spinlock_rt.h:44 [inline]
 __wake_up_common_lock+0x2f/0x1e0 kernel/sched/wait.c:124
 blk_update_request+0x57e/0xe60 block/blk-mq.c:998
 blk_mq_end_request+0x3e/0x70 block/blk-mq.c:1160
 blk_complete_reqs block/blk-mq.c:1235 [inline]
 blk_done_softirq+0x10a/0x160 block/blk-mq.c:1240
 handle_softirqs+0x22f/0x710 kernel/softirq.c:622
 run_ksoftirqd+0xac/0x210 kernel/softirq.c:1063
 smpboot_thread_fn+0x542/0xa60 kernel/smpboot.c:160
 kthread+0x711/0x8a0 kernel/kthread.c:463
 ret_from_fork+0x4bc/0x870 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>

Allocated by task 7682:
 kasan_save_stack mm/kasan/common.c:56 [inline]
 kasan_save_track+0x3e/0x80 mm/kasan/common.c:77
 poison_kmalloc_redzone mm/kasan/common.c:400 [inline]
 __kasan_kmalloc+0x93/0xb0 mm/kasan/common.c:417
 kasan_kmalloc include/linux/kasan.h:262 [inline]
 __kmalloc_cache_noprof+0x1ef/0x6c0 mm/slub.c:5767
 kmalloc_noprof include/linux/slab.h:957 [inline]
 lbmLogInit fs/jfs/jfs_logmgr.c:1821 [inline]
 lmLogInit+0x3db/0x19e0 fs/jfs/jfs_logmgr.c:1269
 open_inline_log fs/jfs/jfs_logmgr.c:1175 [inline]
 lmLogOpen+0x4e1/0xfa0 fs/jfs/jfs_logmgr.c:1069
 jfs_mount_rw+0xe9/0x670 fs/jfs/jfs_mount.c:257
 jfs_fill_super+0x754/0xd80 fs/jfs/super.c:532
 get_tree_bdev_flags+0x40e/0x4d0 fs/super.c:1691
 vfs_get_tree+0x92/0x2b0 fs/super.c:1751
 fc_mount fs/namespace.c:1208 [inline]
 do_new_mount_fc fs/namespace.c:3651 [inline]
 do_new_mount+0x302/0xa10 fs/namespace.c:3727
 do_mount fs/namespace.c:4050 [inline]
 __do_sys_mount fs/namespace.c:4238 [inline]
 __se_sys_mount+0x313/0x410 fs/namespace.c:4215
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xfa/0xfa0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

Freed by task 5925:
 kasan_save_stack mm/kasan/common.c:56 [inline]
 kasan_save_track+0x3e/0x80 mm/kasan/common.c:77
 __kasan_save_free_info+0x46/0x50 mm/kasan/generic.c:587
 kasan_save_free_info mm/kasan/kasan.h:406 [inline]
 poison_slab_object mm/kasan/common.c:252 [inline]
 __kasan_slab_free+0x5c/0x80 mm/kasan/common.c:284
 kasan_slab_free include/linux/kasan.h:234 [inline]
 slab_free_hook mm/slub.c:2539 [inline]
 slab_free mm/slub.c:6634 [inline]
 kfree+0x197/0x950 mm/slub.c:6841
 lbmLogShutdown fs/jfs/jfs_logmgr.c:1864 [inline]
 lmLogShutdown+0x441/0x830 fs/jfs/jfs_logmgr.c:1683
 lmLogClose+0x28a/0x520 fs/jfs/jfs_logmgr.c:1459
 jfs_umount+0x2ef/0x3c0 fs/jfs/jfs_umount.c:114
 jfs_put_super+0x8c/0x190 fs/jfs/super.c:194
 generic_shutdown_super+0x135/0x2c0 fs/super.c:642
 kill_block_super+0x44/0x90 fs/super.c:1722
 deactivate_locked_super+0xbc/0x130 fs/super.c:473
 cleanup_mnt+0x425/0x4c0 fs/namespace.c:1327
 task_work_run+0x1d4/0x260 kernel/task_work.c:227
 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline]
 exit_to_user_mode_loop+0xe9/0x130 kernel/entry/common.c:43
 exit_to_user_mode_prepare include/linux/irq-entry-common.h:225 [inline]
 syscall_exit_to_user_mode_work include/linux/entry-common.h:175 [inline]
 syscall_exit_to_user_mode include/linux/entry-common.h:210 [inline]
 do_syscall_64+0x2bd/0xfa0 arch/x86/entry/syscall_64.c:100
 entry_SYSCALL_64_after_hwframe+0x77/0x7f

The buggy address belongs to the object at ffff888030dcba00
 which belongs to the cache kmalloc-256 of size 256
The buggy address is located 104 bytes inside of
 freed 256-byte region [ffff888030dcba00, ffff888030dcbb00)

The buggy address belongs to the physical page:
page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x30dca
head: order:1 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0
ksm flags: 0x80000000000040(head|node=0|zone=1)
page_type: f5(slab)
raw: 0080000000000040 ffff88813ff26b40 ffffea000157d380 dead000000000003
raw: 0000000000000000 0000000000100010 00000000f5000000 0000000000000000
head: 0080000000000040 ffff88813ff26b40 ffffea000157d380 dead000000000003
head: 0000000000000000 0000000000100010 00000000f5000000 0000000000000000
head: 0080000000000001 ffffea0000c37281 00000000ffffffff 00000000ffffffff
head: 0000000000000000 0000000000000000 00000000ffffffff 0000000000000002
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 1, migratetype Unmovable, gfp_mask 0xd2040(__GFP_IO|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 5919, tgid 5919 (syz-executor), ts 100669428717, free_ts 100657311754
 set_page_owner include/linux/page_owner.h:32 [inline]
 post_alloc_hook+0x240/0x2a0 mm/page_alloc.c:1850
 prep_new_page mm/page_alloc.c:1858 [inline]
 get_page_from_freelist+0x28c0/0x2960 mm/page_alloc.c:3884
 __alloc_frozen_pages_noprof+0x181/0x370 mm/page_alloc.c:5183
 alloc_pages_mpol+0xd1/0x380 mm/mempolicy.c:2416
 alloc_slab_page mm/slub.c:3055 [inline]
 allocate_slab+0x96/0x350 mm/slub.c:3228
 new_slab mm/slub.c:3282 [inline]
 ___slab_alloc+0xb10/0x1400 mm/slub.c:4651
 __slab_alloc+0xc6/0x1f0 mm/slub.c:4774
 __slab_alloc_node mm/slub.c:4850 [inline]
 slab_alloc_node mm/slub.c:5272 [inline]
 __do_kmalloc_node mm/slub.c:5645 [inline]
 __kmalloc_noprof+0x14b/0x7d0 mm/slub.c:5658
 kmalloc_noprof include/linux/slab.h:961 [inline]
 kmalloc_array_noprof include/linux/slab.h:1003 [inline]
 security_inode_init_security+0x107/0x3f0 security/security.c:1868
 __ext4_new_inode+0x3314/0x3cb0 fs/ext4/ialloc.c:1325
 ext4_mkdir+0x3cb/0xc50 fs/ext4/namei.c:3007
 vfs_mkdir+0x306/0x510 fs/namei.c:4453
 do_mkdirat+0x247/0x590 fs/namei.c:4486
 __do_sys_mkdir fs/namei.c:4508 [inline]
 __se_sys_mkdir fs/namei.c:4506 [inline]
 __x64_sys_mkdir+0x6c/0x80 fs/namei.c:4506
 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline]
 do_syscall_64+0xfa/0xfa0 arch/x86/entry/syscall_64.c:94
 entry_SYSCALL_64_after_hwframe+0x77/0x7f
page last free pid 20 tgid 20 stack trace:
 reset_page_owner include/linux/page_owner.h:25 [inline]
 free_pages_prepare mm/page_alloc.c:1394 [inline]
 __free_frozen_pages+0xfb6/0x1140 mm/page_alloc.c:2906
 mm_free_pgd kernel/fork.c:541 [inline]
 __mmdrop+0xb5/0x4f0 kernel/fork.c:683
 rcu_do_batch kernel/rcu/tree.c:2605 [inline]
 rcu_core kernel/rcu/tree.c:2861 [inline]
 rcu_cpu_kthread+0xbf6/0x1b50 kernel/rcu/tree.c:2949
 smpboot_thread_fn+0x542/0xa60 kernel/smpboot.c:160
 kthread+0x711/0x8a0 kernel/kthread.c:463
 ret_from_fork+0x4bc/0x870 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245

Memory state around the buggy address:
 ffff888030dcb900: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
 ffff888030dcb980: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
>ffff888030dcba00: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                                                          ^
 ffff888030dcba80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff888030dcbb00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc
==================================================================

Crashes (30):
Time Kernel Commit Syzkaller Config Log Report Syz repro C repro VM info Assets (help?) Manager Title
2025/11/08 04:01 upstream da32d155f4a8 4e1406b4 .config console log report syz / log [disk image] [vmlinux] [kernel image] [mounted in repro #1 (corrupt fs)] [mounted in repro #2 (corrupt fs)] ci2-upstream-fs KASAN: slab-use-after-free Read in rtlock_slowlock_locked
2025/08/17 16:32 upstream 99bade344cfa 1804e95e .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs general protection fault in rtlock_slowlock_locked
2025/11/16 16:02 upstream 7254a2b52279 f7988ea4 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs KASAN: slab-use-after-free Read in rtlock_slowlock_locked
2025/11/15 18:02 upstream 7a0892d2836e f7988ea4 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs KASAN: slab-use-after-free Read in rtlock_slowlock_locked
2025/11/14 20:01 upstream d4f8cccc6230 f7988ea4 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs KASAN: slab-use-after-free Read in rtlock_slowlock_locked
2025/11/14 18:12 upstream 6da43bbeb691 f7988ea4 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs KASAN: slab-use-after-free Read in rtlock_slowlock_locked
2025/11/12 18:24 upstream 24172e0d7990 07e030de .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs KASAN: slab-use-after-free Read in rtlock_slowlock_locked
2025/11/11 22:09 upstream 24172e0d7990 4e1406b4 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs KASAN: slab-use-after-free Read in rtlock_slowlock_locked
2025/11/09 12:42 upstream 7bb4d6512545 4e1406b4 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs KASAN: slab-use-after-free Read in rtlock_slowlock_locked
2025/11/09 04:11 upstream 7bb4d6512545 4e1406b4 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs KASAN: slab-use-after-free Read in rtlock_slowlock_locked
2025/11/02 09:20 upstream 691d401c7e0e 2c50b6a9 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs KASAN: slab-use-after-free Read in rtlock_slowlock_locked
2025/11/02 04:08 upstream 691d401c7e0e 2c50b6a9 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs KASAN: slab-use-after-free Read in rtlock_slowlock_locked
2025/11/01 01:45 upstream 58fdd8484c05 2c50b6a9 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs KASAN: slab-use-after-free Read in rtlock_slowlock_locked
2025/10/28 01:54 upstream fd57572253bc fd2207e7 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs KASAN: slab-use-after-free Read in rtlock_slowlock_locked
2025/10/27 06:49 upstream 4bb1f7e19c4a c0460fcd .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root KASAN: slab-use-after-free Read in rtlock_slowlock_locked
2025/10/26 16:49 upstream 72761a7e3122 c0460fcd .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root KASAN: slab-use-after-free Read in rtlock_slowlock_locked
2025/10/25 19:13 upstream 9bb956508c9d c0460fcd .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root KASAN: slab-use-after-free Read in rtlock_slowlock_locked
2025/10/21 19:51 upstream 6548d364a3e8 9832ed61 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs KASAN: slab-use-after-free Read in rtlock_slowlock_locked
2025/10/21 04:00 upstream 6548d364a3e8 9832ed61 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs KASAN: slab-use-after-free Read in rtlock_slowlock_locked
2025/10/20 04:51 upstream d9043c79ba68 1c8c8cd8 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs KASAN: slab-use-after-free Read in rtlock_slowlock_locked
2025/10/16 11:02 upstream 7ea30958b305 19568248 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root KASAN: slab-use-after-free Read in rtlock_slowlock_locked
2025/10/14 03:56 upstream 3a8660878839 b6605ba8 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root KASAN: slab-use-after-free Read in rtlock_slowlock_locked
2025/10/13 03:11 upstream 3a8660878839 ff1712fe .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root KASAN: slab-use-after-free Read in rtlock_slowlock_locked
2025/10/11 16:35 upstream 0739473694c4 ff1712fe .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs KASAN: slab-use-after-free Read in rtlock_slowlock_locked
2025/10/11 09:25 upstream 0739473694c4 ff1712fe .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs KASAN: slab-use-after-free Read in rtlock_slowlock_locked
2025/10/07 13:06 upstream c746c3b51698 8ef35d49 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs KASAN: slab-use-after-free Read in rtlock_slowlock_locked
2025/10/02 16:00 upstream 7f7072574127 49379ee0 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs KASAN: slab-use-after-free Read in rtlock_slowlock_locked
2025/09/27 16:11 upstream fec734e8d564 001c9061 .config console log report info [disk image] [vmlinux] [kernel image] ci2-upstream-fs KASAN: slab-use-after-free Read in rtlock_slowlock_locked
2025/09/24 17:46 upstream cec1e6e5d1ab 0abd0691 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root KASAN: slab-use-after-free Read in rtlock_slowlock_locked
2025/08/29 03:24 upstream 07d9df80082b 3e1beec6 .config console log report info [disk image] [vmlinux] [kernel image] ci-upstream-kasan-gce-smack-root KASAN: slab-use-after-free Read in rtlock_slowlock_locked
* Struck through repros no longer work on HEAD.