================================================================== BUG: KASAN: use-after-free in jfs_lazycommit+0x74f/0xa50 fs/jfs/jfs_txnmgr.c:2735 Read of size 4 at addr ffff888074e96694 by task jfsCommit/106 CPU: 1 PID: 106 Comm: jfsCommit Not tainted 6.1.135-syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025 Call Trace: dump_stack_lvl+0x168/0x22e lib/dump_stack.c:106 print_address_description mm/kasan/report.c:316 [inline] print_report+0xa8/0x220 mm/kasan/report.c:427 kasan_report+0x10b/0x140 mm/kasan/report.c:531 jfs_lazycommit+0x74f/0xa50 fs/jfs/jfs_txnmgr.c:2735 kthread+0x29d/0x330 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 Allocated by task 5108: 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] jfs_fill_super+0xd2/0xac0 fs/jfs/super.c:495 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:3057 do_mount fs/namespace.c:3400 [inline] __do_sys_mount fs/namespace.c:3608 [inline] __se_sys_mount+0x2d6/0x3c0 fs/namespace.c:3585 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 4251: 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 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:1186 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 kvfree_call_rcu+0x108/0x870 kernel/rcu/tree.c:3401 drop_sysctl_table+0x2fa/0x430 fs/proc/proc_sysctl.c:1727 drop_sysctl_table+0x2e9/0x430 fs/proc/proc_sysctl.c:1730 unregister_sysctl_table+0x85/0x130 fs/proc/proc_sysctl.c:1765 neigh_sysctl_unregister+0x74/0x90 net/core/neighbour.c:3871 addrconf_sysctl_unregister net/ipv6/addrconf.c:7210 [inline] addrconf_ifdown+0x1711/0x1a10 net/ipv6/addrconf.c:3954 addrconf_notify+0x405/0xf40 net/ipv6/addrconf.c:-1 notifier_call_chain kernel/notifier.c:87 [inline] raw_notifier_call_chain+0xcb/0x160 kernel/notifier.c:455 call_netdevice_notifiers_extack net/core/dev.c:2039 [inline] call_netdevice_notifiers net/core/dev.c:2053 [inline] unregister_netdevice_many+0xfdc/0x1840 net/core/dev.c:10978 sit_exit_batch_net+0x498/0x4e0 net/ipv6/sit.c:1887 ops_exit_list net/core/net_namespace.c:177 [inline] cleanup_net+0x77b/0xb80 net/core/net_namespace.c:640 process_one_work+0x898/0x1160 kernel/workqueue.c:2292 worker_thread+0xaa2/0x1250 kernel/workqueue.c:2439 kthread+0x29d/0x330 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 The buggy address belongs to the object at ffff888074e96600 which belongs to the cache kmalloc-256 of size 256 The buggy address is located 148 bytes inside of 256-byte region [ffff888074e96600, ffff888074e96700) The buggy address belongs to the physical page: page:ffffea0001d3a580 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x74e96 head:ffffea0001d3a580 order:1 compound_mapcount:0 compound_pincount:0 flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff) raw: 00fff00000010200 ffffea0001f1ea00 dead000000000002 ffff888017441b40 raw: 0000000000000000 0000000000100010 00000001ffffffff 0000000000000000 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 4250, tgid 4250 (syz-executor), ts 78016239035, free_ts 78011922584 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:5606 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+0xa0/0x240 mm/slab_common.c:949 kmalloc include/linux/slab.h:568 [inline] kzalloc include/linux/slab.h:699 [inline] new_dir fs/proc/proc_sysctl.c:969 [inline] get_subdir fs/proc/proc_sysctl.c:1013 [inline] __register_sysctl_table+0x96c/0xe70 fs/proc/proc_sysctl.c:1375 mpls_dev_sysctl_register+0x1e4/0x2d0 net/mpls/af_mpls.c:1421 mpls_add_dev net/mpls/af_mpls.c:1476 [inline] mpls_dev_notify+0x24e/0x760 net/mpls/af_mpls.c:1616 notifier_call_chain kernel/notifier.c:87 [inline] raw_notifier_call_chain+0xcb/0x160 kernel/notifier.c:455 call_netdevice_notifiers_extack net/core/dev.c:2039 [inline] call_netdevice_notifiers net/core/dev.c:2053 [inline] register_netdevice+0x1600/0x1aa0 net/core/dev.c:10225 __ip_tunnel_create+0x33e/0x440 net/ipv4/ip_tunnel.c:267 ip_tunnel_init_net+0x28f/0x740 net/ipv4/ip_tunnel.c:1118 vti_init_net+0x2b/0xf0 net/ipv4/ip_vti.c:504 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+0x140/0x260 mm/slub.c:3437 kmalloc_trace+0x26/0xe0 mm/slab_common.c:1026 kmalloc include/linux/slab.h:563 [inline] kzalloc include/linux/slab.h:699 [inline] ref_tracker_alloc+0x129/0x450 lib/ref_tracker.c:85 __netdev_tracker_alloc include/linux/netdevice.h:4051 [inline] netdev_hold include/linux/netdevice.h:4080 [inline] netdev_queue_add_kobject net/core/net-sysfs.c:1661 [inline] netdev_queue_update_kobjects+0x18d/0x480 net/core/net-sysfs.c:1716 register_queue_kobjects net/core/net-sysfs.c:1777 [inline] netdev_register_kobject+0x265/0x310 net/core/net-sysfs.c:2017 register_netdevice+0x12b9/0x1aa0 net/core/dev.c:10192 __ip_tunnel_create+0x33e/0x440 net/ipv4/ip_tunnel.c:267 ip_tunnel_init_net+0x28f/0x740 net/ipv4/ip_tunnel.c:1118 ops_init+0x355/0x5f0 net/core/net_namespace.c:138 setup_net+0x4e1/0xbb0 net/core/net_namespace.c:336 Memory state around the buggy address: ffff888074e96580: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff888074e96600: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff888074e96680: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff888074e96700: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff888074e96780: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ==================================================================