================================================================== BUG: KASAN: slab-use-after-free in __mutex_waiter_is_first kernel/locking/mutex.c:197 [inline] BUG: KASAN: slab-use-after-free in __mutex_lock_common kernel/locking/mutex.c:681 [inline] BUG: KASAN: slab-use-after-free in __mutex_lock+0x6cb/0xcc0 kernel/locking/mutex.c:747 Read of size 8 at addr ffff88807dc09908 by task jfsCommit/112 CPU: 0 PID: 112 Comm: jfsCommit Not tainted 6.6.102-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025 Call Trace: dump_stack_lvl+0x16c/0x230 lib/dump_stack.c:106 print_address_description mm/kasan/report.c:364 [inline] print_report+0xac/0x220 mm/kasan/report.c:468 kasan_report+0x117/0x150 mm/kasan/report.c:581 __mutex_waiter_is_first kernel/locking/mutex.c:197 [inline] __mutex_lock_common kernel/locking/mutex.c:681 [inline] __mutex_lock+0x6cb/0xcc0 kernel/locking/mutex.c:747 jfs_syncpt+0x25/0x90 fs/jfs/jfs_logmgr.c:1039 txEnd+0x2e5/0x520 fs/jfs/jfs_txnmgr.c:549 txLazyCommit fs/jfs/jfs_txnmgr.c:2684 [inline] jfs_lazycommit+0x5a6/0xa60 fs/jfs/jfs_txnmgr.c:2732 kthread+0x2fa/0x390 kernel/kthread.c:388 ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293 Allocated by task 12935: kasan_save_stack mm/kasan/common.c:45 [inline] kasan_set_track+0x4e/0x70 mm/kasan/common.c:52 ____kasan_kmalloc mm/kasan/common.c:374 [inline] __kasan_kmalloc+0x8f/0xa0 mm/kasan/common.c:383 kmalloc include/linux/slab.h:600 [inline] kzalloc include/linux/slab.h:721 [inline] open_inline_log fs/jfs/jfs_logmgr.c:1159 [inline] lmLogOpen+0x2df/0xfb0 fs/jfs/jfs_logmgr.c:1069 jfs_mount_rw+0xea/0x670 fs/jfs/jfs_mount.c:257 jfs_fill_super+0x592/0xac0 fs/jfs/super.c:565 mount_bdev+0x22b/0x2d0 fs/super.c:1643 legacy_get_tree+0xea/0x180 fs/fs_context.c:662 vfs_get_tree+0x8c/0x280 fs/super.c:1764 do_new_mount+0x24b/0xa40 fs/namespace.c:3371 do_mount fs/namespace.c:3711 [inline] __do_sys_mount fs/namespace.c:3920 [inline] __se_sys_mount+0x2da/0x3c0 fs/namespace.c:3897 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x55/0xb0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 Freed by task 8224: kasan_save_stack mm/kasan/common.c:45 [inline] kasan_set_track+0x4e/0x70 mm/kasan/common.c:52 kasan_save_free_info+0x2e/0x50 mm/kasan/generic.c:522 ____kasan_slab_free+0x126/0x1e0 mm/kasan/common.c:236 kasan_slab_free include/linux/kasan.h:164 [inline] slab_free_hook mm/slub.c:1806 [inline] slab_free_freelist_hook+0x130/0x1b0 mm/slub.c:1832 slab_free mm/slub.c:3816 [inline] __kmem_cache_free+0xba/0x1f0 mm/slub.c:3829 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+0x134/0x2b0 fs/super.c:693 kill_block_super+0x44/0x90 fs/super.c:1660 deactivate_locked_super+0x97/0x100 fs/super.c:481 cleanup_mnt+0x429/0x4c0 fs/namespace.c:1250 task_work_run+0x1ce/0x250 kernel/task_work.c:239 resume_user_mode_work include/linux/resume_user_mode.h:49 [inline] exit_to_user_mode_loop+0xe6/0x110 kernel/entry/common.c:177 exit_to_user_mode_prepare+0xb1/0x140 kernel/entry/common.c:210 __syscall_exit_to_user_mode_work kernel/entry/common.c:291 [inline] syscall_exit_to_user_mode+0x1a/0x50 kernel/entry/common.c:302 do_syscall_64+0x61/0xb0 arch/x86/entry/common.c:87 entry_SYSCALL_64_after_hwframe+0x68/0xd2 Last potentially related work creation: kasan_save_stack+0x3e/0x60 mm/kasan/common.c:45 __kasan_record_aux_stack+0xaf/0xc0 mm/kasan/generic.c:492 __call_rcu_common kernel/rcu/tree.c:2721 [inline] call_rcu+0x158/0x930 kernel/rcu/tree.c:2837 sctp_association_free+0x6a1/0x7f0 net/sctp/associola.c:380 sctp_cmd_delete_tcb net/sctp/sm_sideeffect.c:944 [inline] sctp_cmd_interpreter net/sctp/sm_sideeffect.c:1330 [inline] sctp_side_effects net/sctp/sm_sideeffect.c:1198 [inline] sctp_do_sm+0x3e64/0x59a0 net/sctp/sm_sideeffect.c:1169 sctp_assoc_bh_rcv+0x3f2/0x630 net/sctp/associola.c:1052 sctp_backlog_rcv+0x163/0x3e0 net/sctp/input.c:331 sk_backlog_rcv include/net/sock.h:1123 [inline] __release_sock+0x1bd/0x430 net/core/sock.c:2988 release_sock+0x5f/0x1c0 net/core/sock.c:3525 sctp_close+0x6fb/0x900 net/sctp/socket.c:1536 inet_release+0x13d/0x180 net/ipv4/af_inet.c:434 __sock_release net/socket.c:659 [inline] sock_close+0xbd/0x230 net/socket.c:1421 __fput+0x234/0x970 fs/file_table.c:384 task_work_run+0x1ce/0x250 kernel/task_work.c:239 resume_user_mode_work include/linux/resume_user_mode.h:49 [inline] exit_to_user_mode_loop+0xe6/0x110 kernel/entry/common.c:177 exit_to_user_mode_prepare+0xb1/0x140 kernel/entry/common.c:210 __syscall_exit_to_user_mode_work kernel/entry/common.c:291 [inline] syscall_exit_to_user_mode+0x1a/0x50 kernel/entry/common.c:302 do_syscall_64+0x61/0xb0 arch/x86/entry/common.c:87 entry_SYSCALL_64_after_hwframe+0x68/0xd2 Second to last potentially related work creation: kasan_save_stack+0x3e/0x60 mm/kasan/common.c:45 __kasan_record_aux_stack+0xaf/0xc0 mm/kasan/generic.c:492 kvfree_call_rcu+0xee/0x780 kernel/rcu/tree.c:3452 cgroup_migrate_finish+0x1a3/0x370 kernel/cgroup/cgroup.c:2669 cgroup_attach_task+0x5cd/0x830 kernel/cgroup/cgroup.c:2868 cgroup_attach_task_all+0x9a/0xe0 kernel/cgroup/cgroup-v1.c:70 kvm_vm_worker_thread+0xd2/0x570 virt/kvm/kvm_main.c:6195 kthread+0x2fa/0x390 kernel/kthread.c:388 ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:152 ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:293 The buggy address belongs to the object at ffff88807dc09800 which belongs to the cache kmalloc-1k of size 1024 The buggy address is located 264 bytes inside of freed 1024-byte region [ffff88807dc09800, ffff88807dc09c00) The buggy address belongs to the physical page: page:ffffea0001f70200 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x7dc08 head:ffffea0001f70200 order:3 entire_mapcount:0 nr_pages_mapped:0 pincount:0 anon flags: 0xfff00000000840(slab|head|node=0|zone=1|lastcpupid=0x7ff) page_type: 0xffffffff() raw: 00fff00000000840 ffff888017841dc0 0000000000000000 dead000000000001 raw: 0000000000000000 0000000000100010 00000001ffffffff 0000000000000000 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 5785, tgid 5785 (syz-executor), ts 82693760417, free_ts 82632364623 set_page_owner include/linux/page_owner.h:31 [inline] post_alloc_hook+0x1cd/0x210 mm/page_alloc.c:1554 prep_new_page mm/page_alloc.c:1561 [inline] get_page_from_freelist+0x195c/0x19f0 mm/page_alloc.c:3191 __alloc_pages+0x1e3/0x460 mm/page_alloc.c:4457 alloc_slab_page+0x5d/0x170 mm/slub.c:1876 allocate_slab mm/slub.c:2023 [inline] new_slab+0x87/0x2e0 mm/slub.c:2076 ___slab_alloc+0xc6d/0x12f0 mm/slub.c:3230 __slab_alloc mm/slub.c:3329 [inline] __slab_alloc_node mm/slub.c:3382 [inline] slab_alloc_node mm/slub.c:3475 [inline] __kmem_cache_alloc_node+0x1a2/0x260 mm/slub.c:3524 __do_kmalloc_node mm/slab_common.c:1006 [inline] __kmalloc_node+0xa4/0x230 mm/slab_common.c:1014 kmalloc_node include/linux/slab.h:620 [inline] kzalloc_node include/linux/slab.h:732 [inline] qdisc_alloc+0x94/0xa50 net/sched/sch_generic.c:948 qdisc_create_dflt+0x63/0x430 net/sched/sch_generic.c:1009 attach_one_default_qdisc net/sched/sch_generic.c:1173 [inline] netdev_for_each_tx_queue include/linux/netdevice.h:2520 [inline] attach_default_qdiscs net/sched/sch_generic.c:1191 [inline] dev_activate+0x397/0x11a0 net/sched/sch_generic.c:1250 __dev_open+0x338/0x430 net/core/dev.c:1515 __dev_change_flags+0x20e/0x6a0 net/core/dev.c:8673 dev_change_flags+0x88/0x1a0 net/core/dev.c:8745 do_setlink+0xc74/0x3fb0 net/core/rtnetlink.c:2905 __rtnl_newlink net/core/rtnetlink.c:3703 [inline] rtnl_newlink+0x175b/0x2020 net/core/rtnetlink.c:3750 page last free stack trace: reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1154 [inline] free_unref_page_prepare+0x7ce/0x8e0 mm/page_alloc.c:2336 free_unref_page+0x32/0x2e0 mm/page_alloc.c:2429 __slab_free+0x35e/0x410 mm/slub.c:3722 qlink_free mm/kasan/quarantine.c:166 [inline] qlist_free_all+0x75/0xe0 mm/kasan/quarantine.c:185 kasan_quarantine_reduce+0x143/0x160 mm/kasan/quarantine.c:292 __kasan_slab_alloc+0x22/0x80 mm/kasan/common.c:305 kasan_slab_alloc include/linux/kasan.h:188 [inline] slab_post_alloc_hook+0x6e/0x4d0 mm/slab.h:767 slab_alloc_node mm/slub.c:3485 [inline] kmem_cache_alloc_node+0x150/0x330 mm/slub.c:3530 __alloc_skb+0x108/0x2c0 net/core/skbuff.c:640 alloc_skb include/linux/skbuff.h:1284 [inline] nlmsg_new include/net/netlink.h:999 [inline] rtmsg_fib+0xeb/0x4c0 net/ipv4/fib_semantics.c:522 fib_table_insert+0xd61/0x1b50 net/ipv4/fib_trie.c:1385 fib_magic+0x2c5/0x390 net/ipv4/fib_frontend.c:1118 fib_add_ifaddr+0x144/0x5e0 net/ipv4/fib_frontend.c:1140 fib_inetaddr_event+0x140/0x1d0 net/ipv4/fib_frontend.c:1454 notifier_call_chain+0x197/0x390 kernel/notifier.c:93 blocking_notifier_call_chain+0x6a/0x90 kernel/notifier.c:388 Memory state around the buggy address: ffff88807dc09800: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88807dc09880: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff88807dc09900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88807dc09980: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88807dc09a00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================