================================================================== BUG: KASAN: slab-use-after-free in rt_spin_lock+0x88/0x3e0 kernel/locking/spinlock_rt.c:56 Read of size 1 at addr ffff8880238a3ea8 by task ksoftirqd/0/15 CPU: 0 UID: 0 PID: 15 Comm: ksoftirqd/0 Not tainted syzka[ 190.573792][ C0] 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+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 rt_spin_lock+0x88/0x3e0 kernel/locking/spinlock_rt.c:56 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 Allocated by task 6838: 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:5771 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 5802: 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:2543 [inline] slab_free mm/slub.c:6638 [inline] kfree+0x197/0x950 mm/slub.c:6845 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 ffff8880238a3e00 which belongs to the cache kmalloc-256 of size 256 The buggy address is located 168 bytes inside of freed 256-byte region [ffff8880238a3e00, ffff8880238a3f00) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0xffff8880238a3600 pfn:0x238a2 head: order:1 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0 flags: 0x80000000000240(workingset|head|node=0|zone=1) page_type: f5(slab) raw: 0080000000000240 ffff88813ff26b40 ffffea0000ce5f10 ffffea0000d33f90 raw: ffff8880238a3600 000000000010000c 00000000f5000000 0000000000000000 head: 0080000000000240 ffff88813ff26b40 ffffea0000ce5f10 ffffea0000d33f90 head: ffff8880238a3600 000000000010000c 00000000f5000000 0000000000000000 head: 0080000000000001 ffffea00008e2881 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 0x252800(GFP_NOWAIT|__GFP_NORETRY|__GFP_COMP|__GFP_THISNODE), pid 5794, tgid 5794 (syz-executor), ts 102681682234, free_ts 102667967706 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_slab_page mm/slub.c:3061 [inline] allocate_slab+0x71/0x350 mm/slub.c:3232 new_slab mm/slub.c:3286 [inline] ___slab_alloc+0xb10/0x1400 mm/slub.c:4655 __slab_alloc+0xc6/0x1f0 mm/slub.c:4778 __slab_alloc_node mm/slub.c:4854 [inline] slab_alloc_node mm/slub.c:5276 [inline] __do_kmalloc_node mm/slub.c:5649 [inline] __kmalloc_node_noprof+0x2ad/0x7f0 mm/slub.c:5656 kmalloc_array_node_noprof include/linux/slab.h:1075 [inline] alloc_slab_obj_exts+0x3e/0x100 mm/slub.c:2127 __memcg_slab_post_alloc_hook+0x33b/0x810 mm/memcontrol.c:3173 memcg_slab_post_alloc_hook mm/slub.c:2342 [inline] slab_post_alloc_hook mm/slub.c:4989 [inline] slab_alloc_node mm/slub.c:5288 [inline] __do_kmalloc_node mm/slub.c:5649 [inline] __kvmalloc_node_noprof+0x6ee/0x920 mm/slub.c:7108 simple_xattr_alloc+0x48/0xb0 fs/xattr.c:1238 shmem_initxattrs+0x250/0x4b0 mm/shmem.c:4264 security_inode_init_security+0x2a0/0x3f0 security/security.c:1891 shmem_mknod+0x1f6/0x3e0 mm/shmem.c:3851 shmem_mkdir+0x33/0x70 mm/shmem.c:3910 vfs_mkdir+0x306/0x510 fs/namei.c:4453 page last free pid 5798 tgid 5798 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 discard_slab mm/slub.c:3330 [inline] __put_partials+0x149/0x170 mm/slub.c:3876 __slab_free+0x29e/0x370 mm/slub.c:5929 qlink_free mm/kasan/quarantine.c:163 [inline] qlist_free_all+0x97/0x140 mm/kasan/quarantine.c:179 kasan_quarantine_reduce+0x148/0x160 mm/kasan/quarantine.c:286 __kasan_slab_alloc+0x22/0x80 mm/kasan/common.c:352 kasan_slab_alloc include/linux/kasan.h:252 [inline] slab_post_alloc_hook mm/slub.c:4978 [inline] slab_alloc_node mm/slub.c:5288 [inline] kmem_cache_alloc_lru_noprof+0x188/0x6b0 mm/slub.c:5307 sock_alloc_inode+0x28/0xc0 net/socket.c:322 alloc_inode+0x6a/0x1b0 fs/inode.c:346 new_inode_pseudo include/linux/fs.h:3395 [inline] sock_alloc net/socket.c:637 [inline] __sock_create+0x12d/0x9f0 net/socket.c:1569 sock_create net/socket.c:1663 [inline] __sys_socket_create net/socket.c:1700 [inline] __sys_socket+0xd7/0x1b0 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+0xfa/0xfa0 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f Memory state around the buggy address: ffff8880238a3d80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff8880238a3e00: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff8880238a3e80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff8880238a3f00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff8880238a3f80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ==================================================================