================================================================== BUG: KASAN: slab-use-after-free in rt_mutex_owner include/linux/rtmutex.h:52 [inline] BUG: KASAN: slab-use-after-free in rtmutex_spin_on_owner kernel/locking/rtmutex.c:1490 [inline] BUG: KASAN: slab-use-after-free in rtlock_slowlock_locked+0x361c/0x3e70 kernel/locking/rtmutex.c:1866 Read of size 8 at addr ffff888030ff60a0 by task ksoftirqd/0/15 CPU: 0 UID: 0 PID: 15 Comm: ksoftirqd/0 Not tainted syzkaller #0 PREEMPT_{RT,(full)} Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 Call Trace: dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120 print_address_description mm/kasan/report.c:378 [inline] print_report+0xba/0x230 mm/kasan/report.c:482 kasan_report+0x117/0x150 mm/kasan/report.c:595 rt_mutex_owner include/linux/rtmutex.h:52 [inline] rtmutex_spin_on_owner kernel/locking/rtmutex.c:1490 [inline] rtlock_slowlock_locked+0x361c/0x3e70 kernel/locking/rtmutex.c:1866 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+0x165/0x400 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:1007 blk_mq_end_request+0x3e/0x70 block/blk-mq.c:1169 blk_complete_reqs block/blk-mq.c:1244 [inline] blk_done_softirq+0x10a/0x160 block/blk-mq.c:1249 handle_softirqs+0x1de/0x640 kernel/softirq.c:622 run_ksoftirqd+0x52/0x180 kernel/softirq.c:1063 smpboot_thread_fn+0x541/0xa50 kernel/smpboot.c:160 kthread+0x726/0x8b0 kernel/kthread.c:463 ret_from_fork+0x51b/0xa40 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:246 Allocated by task 14719: kasan_save_stack mm/kasan/common.c:57 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:78 poison_kmalloc_redzone mm/kasan/common.c:398 [inline] __kasan_kmalloc+0x93/0xb0 mm/kasan/common.c:415 kasan_kmalloc include/linux/kasan.h:263 [inline] __kmalloc_cache_noprof+0x1f2/0x6b0 mm/slub.c:5776 kmalloc_noprof include/linux/slab.h:957 [inline] lbmLogInit fs/jfs/jfs_logmgr.c:1821 [inline] lmLogInit+0x3e5/0x1a00 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+0xee/0x670 fs/jfs/jfs_mount.c:257 jfs_fill_super+0x754/0xd80 fs/jfs/super.c:532 get_tree_bdev_flags+0x431/0x4f0 fs/super.c:1691 vfs_get_tree+0x92/0x2a0 fs/super.c:1751 fc_mount fs/namespace.c:1199 [inline] do_new_mount_fc fs/namespace.c:3636 [inline] do_new_mount+0x329/0xa50 fs/namespace.c:3712 do_mount fs/namespace.c:4035 [inline] __do_sys_mount fs/namespace.c:4224 [inline] __se_sys_mount+0x31d/0x420 fs/namespace.c:4201 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xe2/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f Freed by task 14719: kasan_save_stack mm/kasan/common.c:57 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:78 kasan_save_free_info+0x46/0x50 mm/kasan/generic.c:584 poison_slab_object mm/kasan/common.c:253 [inline] __kasan_slab_free+0x5c/0x80 mm/kasan/common.c:285 kasan_slab_free include/linux/kasan.h:235 [inline] slab_free_hook mm/slub.c:2540 [inline] slab_free mm/slub.c:6670 [inline] kfree+0x1bb/0x8f0 mm/slub.c:6878 lbmLogShutdown fs/jfs/jfs_logmgr.c:1864 [inline] lmLogInit+0x114c/0x1a00 fs/jfs/jfs_logmgr.c:1415 open_inline_log fs/jfs/jfs_logmgr.c:1175 [inline] lmLogOpen+0x4e1/0xfa0 fs/jfs/jfs_logmgr.c:1069 jfs_mount_rw+0xee/0x670 fs/jfs/jfs_mount.c:257 jfs_fill_super+0x754/0xd80 fs/jfs/super.c:532 get_tree_bdev_flags+0x431/0x4f0 fs/super.c:1691 vfs_get_tree+0x92/0x2a0 fs/super.c:1751 fc_mount fs/namespace.c:1199 [inline] do_new_mount_fc fs/namespace.c:3636 [inline] do_new_mount+0x329/0xa50 fs/namespace.c:3712 do_mount fs/namespace.c:4035 [inline] __do_sys_mount fs/namespace.c:4224 [inline] __se_sys_mount+0x31d/0x420 fs/namespace.c:4201 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xe2/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f The buggy address belongs to the object at ffff888030ff6000 which belongs to the cache kmalloc-256 of size 256 The buggy address is located 160 bytes inside of freed 256-byte region [ffff888030ff6000, ffff888030ff6100) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x30ff6 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 ffff88813fe26b40 ffffea00016a7900 dead000000000003 raw: 0000000000000000 0000000080100010 00000000f5000000 0000000000000000 head: 0080000000000040 ffff88813fe26b40 ffffea00016a7900 dead000000000003 head: 0000000000000000 0000000080100010 00000000f5000000 0000000000000000 head: 0080000000000001 ffffea0000c3fd81 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 5944, tgid 5944 (udevadm), ts 103248851437, free_ts 103031349785 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x228/0x280 mm/page_alloc.c:1884 prep_new_page mm/page_alloc.c:1892 [inline] get_page_from_freelist+0x28bb/0x2950 mm/page_alloc.c:3945 __alloc_frozen_pages_noprof+0x18d/0x380 mm/page_alloc.c:5240 alloc_pages_mpol+0xd1/0x380 mm/mempolicy.c:2486 alloc_slab_page mm/slub.c:3075 [inline] allocate_slab+0x86/0x3a0 mm/slub.c:3248 new_slab mm/slub.c:3302 [inline] ___slab_alloc+0xaf8/0x13d0 mm/slub.c:4656 __slab_alloc+0xc5/0x1f0 mm/slub.c:4779 __slab_alloc_node mm/slub.c:4855 [inline] slab_alloc_node mm/slub.c:5251 [inline] __kmalloc_cache_noprof+0x100/0x6b0 mm/slub.c:5771 kmalloc_noprof include/linux/slab.h:957 [inline] kzalloc_noprof include/linux/slab.h:1094 [inline] smk_fetch+0x95/0x140 security/smack/smack_lsm.c:285 smack_d_instantiate+0x83f/0x990 security/smack/smack_lsm.c:3682 security_d_instantiate+0x106/0x1d0 security/security.c:3601 d_splice_alias_ops+0x71/0x370 fs/dcache.c:3064 __lookup_slow+0x2d2/0x440 fs/namei.c:1866 lookup_slow+0x53/0x70 fs/namei.c:1883 walk_component fs/namei.c:2229 [inline] lookup_last fs/namei.c:2730 [inline] path_lookupat+0x3f5/0x8c0 fs/namei.c:2754 filename_lookup+0x256/0x5d0 fs/namei.c:2783 page last free pid 5794 tgid 5794 stack trace: reset_page_owner include/linux/page_owner.h:25 [inline] free_pages_prepare mm/page_alloc.c:1433 [inline] __free_frozen_pages+0xfc1/0x1130 mm/page_alloc.c:2973 discard_slab mm/slub.c:3346 [inline] __put_partials+0x149/0x170 mm/slub.c:3886 __slab_free+0x2af/0x330 mm/slub.c:5952 qlink_free mm/kasan/quarantine.c:163 [inline] qlist_free_all+0x97/0x100 mm/kasan/quarantine.c:179 kasan_quarantine_reduce+0x148/0x160 mm/kasan/quarantine.c:286 __kasan_slab_alloc+0x22/0x80 mm/kasan/common.c:350 kasan_slab_alloc include/linux/kasan.h:253 [inline] slab_post_alloc_hook mm/slub.c:4953 [inline] slab_alloc_node mm/slub.c:5263 [inline] kmem_cache_alloc_lru_noprof+0x18e/0x6a0 mm/slub.c:5282 sock_alloc_inode+0x28/0xc0 net/socket.c:322 alloc_inode+0x6a/0x1b0 fs/inode.c:346 new_inode_pseudo include/linux/fs.h:2964 [inline] sock_alloc net/socket.c:637 [inline] __sock_create+0x12d/0x9d0 net/socket.c:1569 sock_create net/socket.c:1663 [inline] __sys_socket_create net/socket.c:1700 [inline] __sys_socket+0xd6/0x1b0 net/socket.c:1747 __do_sys_socket net/socket.c:1761 [inline] __se_sys_socket net/socket.c:1759 [inline] __x64_sys_socket+0x7a/0x90 net/socket.c:1759 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xe2/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f Memory state around the buggy address: ffff888030ff5f80: ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ff ffff888030ff6000: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff888030ff6080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff888030ff6100: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff888030ff6180: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ==================================================================