================================================================== BUG: KASAN: use-after-free in __mutex_waiter_is_first kernel/locking/mutex.c:197 [inline] BUG: KASAN: use-after-free in __mutex_lock_common kernel/locking/mutex.c:681 [inline] BUG: KASAN: use-after-free in __mutex_lock+0x56e/0xaf0 kernel/locking/mutex.c:747 Read of size 8 at addr ffff888076b98908 by task jfsCommit/106 CPU: 1 PID: 106 Comm: jfsCommit Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/12/2025 Call Trace: dump_stack_lvl+0x168/0x22e lib/dump_stack.c:106 print_address_description mm/kasan/report.c:316 [inline] print_report+0xa8/0x210 mm/kasan/report.c:420 kasan_report+0x10b/0x140 mm/kasan/report.c:524 __mutex_waiter_is_first kernel/locking/mutex.c:197 [inline] __mutex_lock_common kernel/locking/mutex.c:681 [inline] __mutex_lock+0x56e/0xaf0 kernel/locking/mutex.c:747 jfs_syncpt+0x21/0x90 fs/jfs/jfs_logmgr.c:1039 txEnd+0x2e1/0x520 fs/jfs/jfs_txnmgr.c:549 txLazyCommit fs/jfs/jfs_txnmgr.c:2684 [inline] jfs_lazycommit+0x5a2/0xa50 fs/jfs/jfs_txnmgr.c:2732 kthread+0x29d/0x330 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 Allocated by task 8634: kasan_save_stack mm/kasan/common.c:45 [inline] kasan_set_track+0x4b/0x70 mm/kasan/common.c:52 ____kasan_kmalloc mm/kasan/common.c:374 [inline] __kasan_kmalloc+0x8e/0xa0 mm/kasan/common.c:383 kmalloc include/linux/slab.h:563 [inline] kzalloc include/linux/slab.h:699 [inline] open_inline_log fs/jfs/jfs_logmgr.c:1159 [inline] lmLogOpen+0x2c0/0xf90 fs/jfs/jfs_logmgr.c:1069 jfs_mount_rw+0xf2/0x5c0 fs/jfs/jfs_mount.c:253 jfs_fill_super+0x58e/0xac0 fs/jfs/super.c:565 mount_bdev+0x287/0x3c0 fs/super.c:1443 legacy_get_tree+0xe6/0x180 fs/fs_context.c:632 vfs_get_tree+0x88/0x270 fs/super.c:1573 do_new_mount+0x24a/0xa40 fs/namespace.c:3069 do_mount fs/namespace.c:3412 [inline] __do_sys_mount fs/namespace.c:3620 [inline] __se_sys_mount+0x2d6/0x3c0 fs/namespace.c:3597 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 Freed by task 4277: kasan_save_stack mm/kasan/common.c:45 [inline] kasan_set_track+0x4b/0x70 mm/kasan/common.c:52 kasan_save_free_info+0x2d/0x50 mm/kasan/generic.c:516 ____kasan_slab_free+0x126/0x1e0 mm/kasan/common.c:236 kasan_slab_free include/linux/kasan.h:177 [inline] slab_free_hook mm/slub.c:1724 [inline] slab_free_freelist_hook+0x131/0x1a0 mm/slub.c:1750 slab_free mm/slub.c:3661 [inline] __kmem_cache_free+0xb6/0x1f0 mm/slub.c:3674 lmLogClose+0x293/0x520 fs/jfs/jfs_logmgr.c:-1 jfs_umount+0x28f/0x360 fs/jfs/jfs_umount.c:116 jfs_put_super+0x88/0x190 fs/jfs/super.c:194 generic_shutdown_super+0x130/0x340 fs/super.c:501 kill_block_super+0x7c/0xe0 fs/super.c:1470 deactivate_locked_super+0x93/0xf0 fs/super.c:332 cleanup_mnt+0x463/0x4f0 fs/namespace.c:1182 task_work_run+0x1ca/0x250 kernel/task_work.c:203 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:292 [inline] syscall_exit_to_user_mode+0x16/0x40 kernel/entry/common.c:303 do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:87 entry_SYSCALL_64_after_hwframe+0x68/0xd2 Last potentially related work creation: kasan_save_stack+0x3a/0x60 mm/kasan/common.c:45 __kasan_record_aux_stack+0xb2/0xc0 mm/kasan/generic.c:486 call_rcu+0x154/0x980 kernel/rcu/tree.c:2849 sctp_association_free+0x69d/0x7e0 net/sctp/associola.c:382 sctp_cmd_delete_tcb net/sctp/sm_sideeffect.c:944 [inline] sctp_cmd_interpreter net/sctp/sm_sideeffect.c:1331 [inline] sctp_side_effects net/sctp/sm_sideeffect.c:1199 [inline] sctp_do_sm+0x36a4/0x5500 net/sctp/sm_sideeffect.c:1170 sctp_assoc_bh_rcv+0x3ee/0x630 net/sctp/associola.c:1054 sctp_backlog_rcv+0x15f/0x3e0 net/sctp/input.c:346 sk_backlog_rcv include/net/sock.h:1119 [inline] __release_sock+0x1b9/0x420 net/core/sock.c:2939 release_sock+0x5b/0x1b0 net/core/sock.c:3503 sctp_wait_for_connect+0x37e/0x680 net/sctp/socket.c:9354 __sctp_connect+0xabb/0xd20 net/sctp/socket.c:1246 __sctp_setsockopt_connectx net/sctp/socket.c:1335 [inline] sctp_getsockopt_connectx3+0x2c0/0x440 net/sctp/socket.c:1420 sctp_getsockopt+0x3ab/0x8a0 net/sctp/socket.c:8126 __sys_getsockopt+0x1b0/0x230 net/socket.c:2332 __do_sys_getsockopt net/socket.c:2347 [inline] __se_sys_getsockopt net/socket.c:2344 [inline] __x64_sys_getsockopt+0xb1/0xc0 net/socket.c:2344 do_syscall_x64 arch/x86/entry/common.c:51 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:81 entry_SYSCALL_64_after_hwframe+0x68/0xd2 The buggy address belongs to the object at ffff888076b98800 which belongs to the cache kmalloc-1k of size 1024 The buggy address is located 264 bytes inside of 1024-byte region [ffff888076b98800, ffff888076b98c00) The buggy address belongs to the physical page: page:ffffea0001dae600 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x76b98 head:ffffea0001dae600 order:3 compound_mapcount:0 compound_pincount:0 flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff) raw: 00fff00000010200 0000000000000000 dead000000000001 ffff888017441dc0 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 4275, tgid 4275 (syz-executor), ts 60771341539, free_ts 60659725064 set_page_owner include/linux/page_owner.h:31 [inline] post_alloc_hook+0x173/0x1a0 mm/page_alloc.c:2532 prep_new_page mm/page_alloc.c:2539 [inline] get_page_from_freelist+0x1a26/0x1ac0 mm/page_alloc.c:4328 __alloc_pages+0x1df/0x4e0 mm/page_alloc.c:5614 alloc_slab_page+0x5d/0x160 mm/slub.c:1794 allocate_slab mm/slub.c:1939 [inline] new_slab+0x87/0x2c0 mm/slub.c:1992 ___slab_alloc+0xbc6/0x1220 mm/slub.c:3180 __slab_alloc mm/slub.c:3279 [inline] slab_alloc_node mm/slub.c:3364 [inline] __kmem_cache_alloc_node+0x1a0/0x260 mm/slub.c:3437 __do_kmalloc_node mm/slab_common.c:935 [inline] __kmalloc_node+0xa0/0x240 mm/slab_common.c:943 kmalloc_node include/linux/slab.h:589 [inline] kzalloc_node include/linux/slab.h:710 [inline] qdisc_alloc+0x95/0xa50 net/sched/sch_generic.c:948 qdisc_create_dflt+0x5f/0x4b0 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:2465 [inline] attach_default_qdiscs net/sched/sch_generic.c:1191 [inline] dev_activate+0x393/0x11a0 net/sched/sch_generic.c:1250 __dev_open+0x334/0x420 net/core/dev.c:1497 __dev_change_flags+0x20a/0x6a0 net/core/dev.c:8638 dev_change_flags+0x82/0x1a0 net/core/dev.c:8709 do_setlink+0xc31/0x3c40 net/core/rtnetlink.c:2833 __rtnl_newlink net/core/rtnetlink.c:3608 [inline] rtnl_newlink+0x17d6/0x1ff0 net/core/rtnetlink.c:3655 page last free stack trace: reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1459 [inline] free_pcp_prepare mm/page_alloc.c:1509 [inline] free_unref_page_prepare+0x8b4/0x9a0 mm/page_alloc.c:3384 free_unref_page+0x2e/0x3f0 mm/page_alloc.c:3479 qlink_free mm/kasan/quarantine.c:168 [inline] qlist_free_all+0x76/0xe0 mm/kasan/quarantine.c:187 kasan_quarantine_reduce+0x144/0x160 mm/kasan/quarantine.c:294 __kasan_slab_alloc+0x1e/0x80 mm/kasan/common.c:305 kasan_slab_alloc include/linux/kasan.h:201 [inline] slab_post_alloc_hook+0x4b/0x480 mm/slab.h:737 slab_alloc_node mm/slub.c:3398 [inline] kmem_cache_alloc_node+0x14d/0x320 mm/slub.c:3443 __alloc_skb+0xfc/0x7e0 net/core/skbuff.c:505 alloc_skb include/linux/skbuff.h:1271 [inline] mld_newpack+0x12a/0xc60 net/ipv6/mcast.c:1745 add_grhead+0x5a/0x2a0 net/ipv6/mcast.c:1856 add_grec+0x13b2/0x1660 net/ipv6/mcast.c:1994 mld_send_initial_cr+0xed/0x240 net/ipv6/mcast.c:2241 mld_dad_work+0x3c/0x270 net/ipv6/mcast.c:2267 process_one_work+0x898/0x1160 kernel/workqueue.c:2292 worker_thread+0xaa2/0x1250 kernel/workqueue.c:2439 kthread+0x29d/0x330 kernel/kthread.c:376 Memory state around the buggy address: ffff888076b98800: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888076b98880: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff888076b98900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff888076b98980: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff888076b98a00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================