================================================================== 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:1393 [inline] BUG: KASAN: slab-use-after-free in rt_mutex_try_acquire kernel/locking/rtmutex.c:325 [inline] BUG: KASAN: slab-use-after-free in __rt_mutex_lock kernel/locking/rtmutex.c:1828 [inline] BUG: KASAN: slab-use-after-free in __mutex_lock_common kernel/locking/rtmutex_api.c:535 [inline] BUG: KASAN: slab-use-after-free in mutex_lock_nested+0xc9/0x1d0 kernel/locking/rtmutex_api.c:553 Read of size 8 at addr ffff888035aeb148 by task jfsCommit/120 CPU: 1 UID: 0 PID: 120 Comm: jfsCommit Not tainted syzkaller #0 PREEMPT_{RT,(full)} Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 03/18/2026 Call Trace: dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120 print_address_description+0x55/0x1e0 mm/kasan/report.c:378 print_report+0x58/0x70 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:1393 [inline] rt_mutex_try_acquire kernel/locking/rtmutex.c:325 [inline] __rt_mutex_lock kernel/locking/rtmutex.c:1828 [inline] __mutex_lock_common kernel/locking/rtmutex_api.c:535 [inline] mutex_lock_nested+0xc9/0x1d0 kernel/locking/rtmutex_api.c:553 jfs_syncpt+0x25/0x90 fs/jfs/jfs_logmgr.c:1037 txEnd+0x2e5/0x530 fs/jfs/jfs_txnmgr.c:551 txLazyCommit fs/jfs/jfs_txnmgr.c:2686 [inline] jfs_lazycommit+0x55a/0xa10 fs/jfs/jfs_txnmgr.c:2735 kthread+0x388/0x470 kernel/kthread.c:436 ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Allocated by task 7303: 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:5415 kmalloc_noprof include/linux/slab.h:950 [inline] kzalloc_noprof include/linux/slab.h:1188 [inline] open_inline_log fs/jfs/jfs_logmgr.c:1157 [inline] lmLogOpen+0x2d1/0xfa0 fs/jfs/jfs_logmgr.c:1067 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:3758 [inline] do_new_mount+0x341/0xd30 fs/namespace.c:3834 do_mount fs/namespace.c:4167 [inline] __do_sys_mount fs/namespace.c:4383 [inline] __se_sys_mount+0x31d/0x420 fs/namespace.c:4360 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x15f/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f Freed by task 6569: 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:2689 [inline] slab_free mm/slub.c:6246 [inline] kfree+0x1c5/0x6c0 mm/slub.c:6561 lmLogClose+0x297/0x520 fs/jfs/jfs_logmgr.c:-1 jfs_umount+0x2fb/0x3d0 fs/jfs/jfs_umount.c:124 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:207 [inline] syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:238 [inline] syscall_exit_to_user_mode include/linux/entry-common.h:328 [inline] do_syscall_64+0x33e/0xf80 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f The buggy address belongs to the object at ffff888035aeb000 which belongs to the cache kmalloc-1k of size 1024 The buggy address is located 328 bytes inside of freed 1024-byte region [ffff888035aeb000, ffff888035aeb400) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x35ae8 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 ffff88801a020dc0 dead000000000100 dead000000000122 raw: 0000000000000000 0000000800100010 00000000f5000000 0000000000000000 head: 0080000000000040 ffff88801a020dc0 dead000000000100 dead000000000122 head: 0000000000000000 0000000800100010 00000000f5000000 0000000000000000 head: 0080000000000003 fffffffffffffe01 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 0xd2820(GFP_ATOMIC|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 5792, tgid 5792 (syz-executor), ts 77960905089, free_ts 58036416702 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x231/0x280 mm/page_alloc.c:1860 prep_new_page mm/page_alloc.c:1868 [inline] get_page_from_freelist+0x27c8/0x2840 mm/page_alloc.c:3948 __alloc_froz[ 207.212509][ T120] __alloc_frozen_pages_noprof+0x18d/0x380 mm/page_alloc.c:5228 alloc_slab_page mm/slub.c:3278 [inline] allocate_slab+0x77/0x660 mm/slub.c:3467 new_slab mm/slub.c:3525 [inline] refill_objects+0x33c/0x3d0 mm/slub.c:7251 refill_sheaf mm/slub.c:2816 [inline] __pcs_replace_empty_main+0x373/0x720 mm/slub.c:4651 alloc_from_pcs mm/slub.c:4749 [inline] slab_alloc_node mm/slub.c:4883 [inline] __kmalloc_cache_noprof+0x44e/0x690 mm/slub.c:5410 kmalloc_noprof include/linux/slab.h:950 [inline] kzalloc_noprof include/linux/slab.h:1188 [inline] batadv_hardif_add_interface net/batman-adv/hard-interface.c:874 [inline] batadv_hard_if_event+0xe7a/0x1700 net/batman-adv/hard-interface.c:958 notifier_call_chain+0x1ad/0x3d0 kernel/notifier.c:85 call_netdevice_notifiers_extack net/core/dev.c:2287 [inline] call_netdevice_notifiers net/core/dev.c:2301 [inline] register_netdevice+0x1751/0x1d10 net/core/dev.c:11508 veth_newlink+0x67b/0xb70 drivers/net/veth.c:1889 rtnl_newlink_create+0x329/0xb70 net/core/rtnetlink.c:3862 __rtnl_newlink net/core/rtnetlink.c:3993 [inline] rtnl_newlink+0x166a/0x1bb0 net/core/rtnetlink.c:4108 rtnetlink_rcv_msg+0x7d5/0xbe0 net/core/rtnetlink.c:6994 netlink_rcv_skb+0x232/0x4b0 net/netlink/af_netlink.c:2550 netlink_unicast_kernel net/netlink/af_netlink.c:1318 [inline] netlink_unicast+0x780/0x920 net/netlink/af_netlink.c:1344 page last free pid 5458 tgid 5458 stack trace: reset_page_owner include/linux/page_owner.h:25 [inline] __free_pages_prepare mm/page_alloc.c:1404 [inline] __free_frozen_pages+0xfa6/0x10f0 mm/page_alloc.c:2945 __slab_free+0x252/0x2a0 mm/slub.c:5608 qlink_free mm/kasan/quarantine.c:163 [inline] qlist_free_all+0x99/0x100 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:4569 [inline] slab_alloc_node mm/slub.c:4898 [inline] kmem_cache_alloc_noprof+0x33b/0x680 mm/slub.c:4905 vm_area_alloc+0x24/0x140 mm/vma_init.c:32 __mmap_new_vma mm/vma.c:2547 [inline] __mmap_region mm/vma.c:2771 [inline] mmap_region+0x120a/0x2280 mm/vma.c:2856 do_mmap+0xc2f/0x10c0 mm/mmap.c:560 vm_mmap_pgoff+0x2cc/0x4f0 mm/util.c:581 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x15f/0xf80 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f Memory state around the buggy address: ffff888035aeb000: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888035aeb080: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff888035aeb100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff888035aeb180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888035aeb200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================