================================================================== BUG: KASAN: slab-use-after-free in rt_spin_lock+0x83/0x400 kernel/locking/spinlock_rt.c:56 Read of size 1 at addr ffff8880364fa4a8 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 01/13/2026 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 __kasan_check_byte+0x2a/0x40 mm/kasan/common.c:574 kasan_check_byte include/linux/kasan.h:402 [inline] lock_acquire+0x84/0x330 kernel/locking/lockdep.c:5842 rt_spin_lock+0x83/0x400 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: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 6315: 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:5780 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 6315: 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:6674 [inline] kfree+0x1bb/0x8f0 mm/slub.c:6882 lbmLogShutdown fs/jfs/jfs_logmgr.c:1864 [inline] lmLogShutdown+0x456/0x850 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_fill_super+0x9c5/0xd80 fs/jfs/super.c:567 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 ffff8880364fa400 which belongs to the cache kmalloc-256 of size 256 The buggy address is located 168 bytes inside of freed 256-byte region [ffff8880364fa400, ffff8880364fa500) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x364fa head: order:1 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0 flags: 0x80000000000040(head|node=0|zone=1) page_type: f5(slab) raw: 0080000000000040 ffff88813fea6b40 ffffea00009fc300 dead000000000004 raw: 0000000000000000 0000000000100010 00000000f5000000 0000000000000000 head: 0080000000000040 ffff88813fea6b40 ffffea00009fc300 dead000000000004 head: 0000000000000000 0000000000100010 00000000f5000000 0000000000000000 head: 0080000000000001 ffffea0000d93e81 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 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 5815, tgid 5815 (syz-executor), ts 166446550902, free_ts 165635672801 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] __do_kmalloc_node mm/slub.c:5656 [inline] __kmalloc_noprof+0x15e/0x7c0 mm/slub.c:5669 kmalloc_noprof include/linux/slab.h:961 [inline] kzalloc_noprof include/linux/slab.h:1094 [inline] fib_create_info+0x171d/0x31f0 net/ipv4/fib_semantics.c:1402 fib_table_insert+0xc8/0x1b50 net/ipv4/fib_trie.c:1212 fib_magic+0x2e4/0x3d0 net/ipv4/fib_frontend.c:1134 fib_add_ifaddr+0x3fb/0x5f0 net/ipv4/fib_frontend.c:1178 fib_netdev_event+0x382/0x490 net/ipv4/fib_frontend.c:1516 notifier_call_chain+0x19d/0x3a0 kernel/notifier.c:85 call_netdevice_notifiers_extack net/core/dev.c:2281 [inline] call_netdevice_notifiers net/core/dev.c:2295 [inline] __dev_notify_flags+0x1a9/0x310 net/core/dev.c:9788 netif_change_flags+0xe8/0x1a0 net/core/dev.c:9817 page last free pid 5818 tgid 5818 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 __slab_free+0x2e6/0x330 mm/slub.c:6008 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_node_noprof+0x22f/0x6d0 mm/slub.c:5315 kmalloc_reserve+0xbd/0x290 net/core/skbuff.c:586 __alloc_skb+0x204/0x390 net/core/skbuff.c:690 alloc_skb include/linux/skbuff.h:1383 [inline] nlmsg_new include/net/netlink.h:1055 [inline] netlink_ack+0x146/0xa50 net/netlink/af_netlink.c:2487 netlink_rcv_skb+0x2b6/0x4b0 net/netlink/af_netlink.c:2556 netlink_unicast_kernel net/netlink/af_netlink.c:1318 [inline] netlink_unicast+0x831/0x9f0 net/netlink/af_netlink.c:1344 netlink_sendmsg+0x813/0xb40 net/netlink/af_netlink.c:1894 sock_sendmsg_nosec net/socket.c:727 [inline] __sock_sendmsg+0x21c/0x270 net/socket.c:742 __sys_sendto+0x3d0/0x560 net/socket.c:2206 __do_sys_sendto net/socket.c:2213 [inline] __se_sys_sendto net/socket.c:2209 [inline] __x64_sys_sendto+0xde/0x100 net/socket.c:2209 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0xe2/0xf80 arch/x86/entry/syscall_64.c:94 Memory state around the buggy address: ffff8880364fa380: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff8880364fa400: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff8880364fa480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff8880364fa500: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff8880364fa580: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ==================================================================