================================================================== BUG: KASAN: slab-use-after-free in rt_mutex_owner include/linux/rtmutex.h:52 [inline] BUG: KASAN: slab-use-after-free in rt_mutex_slowtrylock kernel/locking/rtmutex.c:1384 [inline] BUG: KASAN: slab-use-after-free in rt_mutex_try_acquire kernel/locking/rtmutex.c:320 [inline] BUG: KASAN: slab-use-after-free in __rt_mutex_lock kernel/locking/rtmutex.c:1812 [inline] BUG: KASAN: slab-use-after-free in __mutex_lock_common kernel/locking/rtmutex_api.c:534 [inline] BUG: KASAN: slab-use-after-free in mutex_lock_nested+0xc9/0x1d0 kernel/locking/rtmutex_api.c:552 Read of size 8 at addr ffff888021325948 by task jfsCommit/120 CPU: 0 UID: 0 PID: 120 Comm: jfsCommit Not tainted syzkaller #0 PREEMPT_{RT,(full)} Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2026 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] rt_mutex_slowtrylock kernel/locking/rtmutex.c:1384 [inline] rt_mutex_try_acquire kernel/locking/rtmutex.c:320 [inline] __rt_mutex_lock kernel/locking/rtmutex.c:1812 [inline] __mutex_lock_common kernel/locking/rtmutex_api.c:534 [inline] mutex_lock_nested+0xc9/0x1d0 kernel/locking/rtmutex_api.c:552 jfs_syncpt+0x25/0x90 fs/jfs/jfs_logmgr.c:1039 txEnd+0x2e5/0x530 fs/jfs/jfs_txnmgr.c:550 txLazyCommit fs/jfs/jfs_txnmgr.c:2685 [inline] jfs_lazycommit+0x55a/0xa10 fs/jfs/jfs_txnmgr.c:2734 kthread+0x388/0x470 kernel/kthread.c:467 ret_from_fork+0x51e/0xb90 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Allocated by task 13581: 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+0x3a6/0x690 mm/slub.c:5358 kmalloc_noprof include/linux/slab.h:950 [inline] kzalloc_noprof include/linux/slab.h:1188 [inline] open_inline_log fs/jfs/jfs_logmgr.c:1159 [inline] lmLogOpen+0x2d1/0xfa0 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:1694 vfs_get_tree+0x92/0x2a0 fs/super.c:1754 fc_mount fs/namespace.c:1193 [inline] do_new_mount_fc fs/namespace.c:3763 [inline] do_new_mount+0x341/0xd30 fs/namespace.c:3839 do_mount fs/namespace.c:4172 [inline] __do_sys_mount fs/namespace.c:4361 [inline] __se_sys_mount+0x31d/0x420 fs/namespace.c:4338 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x14d/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f Freed by task 13106: 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:2692 [inline] slab_free mm/slub.c:6143 [inline] kfree+0x1c1/0x6c0 mm/slub.c:6461 lmLogClose+0x297/0x520 fs/jfs/jfs_logmgr.c:-1 jfs_umount+0x2ef/0x3c0 fs/jfs/jfs_umount.c:114 jfs_put_super+0x8c/0x190 fs/jfs/super.c:194 generic_shutdown_super+0x13d/0x2d0 fs/super.c:646 kill_block_super+0x44/0x90 fs/super.c:1725 deactivate_locked_super+0xbc/0x130 fs/super.c:476 cleanup_mnt+0x437/0x4d0 fs/namespace.c:1312 task_work_run+0x1d9/0x270 kernel/task_work.c:233 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline] __exit_to_user_mode_loop kernel/entry/common.c:67 [inline] exit_to_user_mode_loop+0xed/0x480 kernel/entry/common.c:98 __exit_to_user_mode_prepare include/linux/irq-entry-common.h:226 [inline] syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:256 [inline] syscall_exit_to_user_mode include/linux/entry-common.h:325 [inline] do_syscall_64+0x32d/0xf80 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f The buggy address belongs to the object at ffff888021325800 which belongs to the cache kmalloc-1k of size 1024 The buggy address is located 328 bytes inside of freed 1024-byte region [ffff888021325800, ffff888021325c00) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x21320 head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0 flags: 0x80000000000040(head|node=0|zone=1) page_type: f5(slab) raw: 0080000000000040 ffff88813fe1cdc0 dead000000000100 dead000000000122 raw: 0000000000000000 0000000800100010 00000000f5000000 0000000000000000 head: 0080000000000040 ffff88813fe1cdc0 dead000000000100 dead000000000122 head: 0000000000000000 0000000800100010 00000000f5000000 0000000000000000 head: 0080000000000003 ffffea000084c801 00000000ffffffff 00000000ffffffff head: 0000000000000000 0000000000000000 00000000ffffffff 0000000000000008 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 3, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 6034, tgid 6031 (syz.3.28), ts 97338508271, free_ts 97335659095 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x231/0x280 mm/page_alloc.c:1889 prep_new_page mm/page_alloc.c:1897 [inline] get_page_from_freelist+0x28bb/0x2950 mm/page_alloc.c:3962 __alloc_frozen_pages_noprof+0x18d/0x380 mm/page_alloc.c:5250 alloc_slab_page mm/slub.c:3269 [inline] allocate_slab+0x77/0x660 mm/slub.c:3458 new_slab mm/slub.c:3516 [inline] refill_objects+0x334/0x3c0 mm/slub.c:7153 refill_sheaf mm/slub.c:2818 [inline] __pcs_replace_empty_main+0x328/0x5f0 mm/slub.c:4592 alloc_from_pcs mm/slub.c:4695 [inline] slab_alloc_node mm/slub.c:4829 [inline] __kmalloc_cache_noprof+0x44e/0x690 mm/slub.c:5353 kmalloc_noprof include/linux/slab.h:950 [inline] kzalloc_noprof include/linux/slab.h:1188 [inline] ocfs2_init_file_private fs/ocfs2/file.c:57 [inline] ocfs2_dir_open+0x4f/0xe0 fs/ocfs2/file.c:156 do_dentry_open+0x83d/0x13e0 fs/open.c:949 vfs_open+0x3b/0x350 fs/open.c:1081 do_open fs/namei.c:4671 [inline] path_openat+0x2e43/0x38a0 fs/namei.c:4830 do_file_open+0x23e/0x4a0 fs/namei.c:4859 do_sys_openat2+0x113/0x200 fs/open.c:1366 do_sys_open fs/open.c:1372 [inline] __do_sys_openat fs/open.c:1388 [inline] __se_sys_openat fs/open.c:1383 [inline] __x64_sys_openat+0x138/0x170 fs/open.c:1383 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x14d/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f page last free pid 1182 tgid 1182 stack trace: reset_page_owner include/linux/page_owner.h:25 [inline] __free_pages_prepare mm/page_alloc.c:1433 [inline] __free_frozen_pages+0xfe3/0x1170 mm/page_alloc.c:2978 __folio_put+0x25d/0x310 mm/swap.c:112 put_netmem include/net/netmem.h:420 [inline] skb_page_unref include/linux/skbuff_ref.h:43 [inline] __skb_frag_unref include/linux/skbuff_ref.h:56 [inline] skb_release_data+0x4cb/0x940 net/core/skbuff.c:1122 skb_release_all net/core/skbuff.c:1203 [inline] napi_consume_skb+0x1f2/0x2c0 net/core/skbuff.c:1550 skb_defer_free_flush+0x191/0x260 net/core/dev.c:6823 net_rx_action+0x4a6/0xe00 net/core/dev.c:7891 handle_softirqs+0x1de/0x6f0 kernel/softirq.c:622 __do_softirq kernel/softirq.c:656 [inline] __local_bh_enable_ip+0x170/0x2b0 kernel/softirq.c:302 local_bh_enable include/linux/bottom_half.h:33 [inline] irq_forced_thread_fn+0xe9/0x120 kernel/irq/manage.c:1168 irq_thread+0x4c9/0x740 kernel/irq/manage.c:1271 kthread+0x388/0x470 kernel/kthread.c:467 ret_from_fork+0x51e/0xb90 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: ffff888021325800: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888021325880: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff888021325900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff888021325980: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888021325a00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================