================================================================== BUG: KASAN: use-after-free in jfs_lazycommit+0x761/0xb40 fs/jfs/jfs_txnmgr.c:2770 Read of size 4 at addr ffff88805c7dfa94 by task jfsCommit/276 CPU: 0 PID: 276 Comm: jfsCommit Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 04/18/2026 Call Trace: dump_stack_lvl+0x188/0x250 lib/dump_stack.c:106 print_address_description+0x60/0x2d0 mm/kasan/report.c:248 __kasan_report mm/kasan/report.c:434 [inline] kasan_report+0xdf/0x130 mm/kasan/report.c:451 jfs_lazycommit+0x761/0xb40 fs/jfs/jfs_txnmgr.c:2770 kthread+0x436/0x520 kernel/kthread.c:334 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287 Allocated by task 25838: kasan_save_stack mm/kasan/common.c:38 [inline] kasan_set_track mm/kasan/common.c:46 [inline] set_alloc_info mm/kasan/common.c:434 [inline] ____kasan_kmalloc mm/kasan/common.c:513 [inline] __kasan_kmalloc+0xb5/0xf0 mm/kasan/common.c:522 kmalloc include/linux/slab.h:607 [inline] kzalloc include/linux/slab.h:738 [inline] jfs_fill_super+0xd8/0xb00 fs/jfs/super.c:500 mount_bdev+0x287/0x3c0 fs/super.c:1400 legacy_get_tree+0xe6/0x180 fs/fs_context.c:611 vfs_get_tree+0x88/0x270 fs/super.c:1530 do_new_mount+0x24a/0xa40 fs/namespace.c:3034 do_mount fs/namespace.c:3377 [inline] __do_sys_mount fs/namespace.c:3585 [inline] __se_sys_mount+0x2e3/0x3d0 fs/namespace.c:3562 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x66/0xd0 Freed by task 25481: kasan_save_stack mm/kasan/common.c:38 [inline] kasan_set_track+0x4b/0x70 mm/kasan/common.c:46 kasan_set_free_info+0x1f/0x40 mm/kasan/generic.c:360 ____kasan_slab_free+0xd5/0x110 mm/kasan/common.c:366 kasan_slab_free include/linux/kasan.h:230 [inline] slab_free_hook mm/slub.c:1710 [inline] slab_free_freelist_hook+0xea/0x170 mm/slub.c:1736 slab_free mm/slub.c:3504 [inline] kfree+0xef/0x2a0 mm/slub.c:4564 generic_shutdown_super+0x130/0x300 fs/super.c:475 kill_block_super+0x7c/0xe0 fs/super.c:1427 deactivate_locked_super+0x93/0xf0 fs/super.c:335 cleanup_mnt+0x42d/0x4e0 fs/namespace.c:1148 task_work_run+0x125/0x1a0 kernel/task_work.c:188 tracehook_notify_resume include/linux/tracehook.h:189 [inline] exit_to_user_mode_loop+0x10f/0x130 kernel/entry/common.c:181 exit_to_user_mode_prepare+0xee/0x180 kernel/entry/common.c:214 __syscall_exit_to_user_mode_work kernel/entry/common.c:296 [inline] syscall_exit_to_user_mode+0x16/0x40 kernel/entry/common.c:307 do_syscall_64+0x58/0xa0 arch/x86/entry/common.c:86 entry_SYSCALL_64_after_hwframe+0x66/0xd0 Last potentially related work creation: kasan_save_stack+0x35/0x60 mm/kasan/common.c:38 kasan_record_aux_stack+0xb8/0x100 mm/kasan/generic.c:348 kvfree_call_rcu+0x105/0x7d0 kernel/rcu/tree.c:3600 inetdev_event+0x33a/0x1370 net/ipv4/devinet.c:1597 notifier_call_chain kernel/notifier.c:83 [inline] raw_notifier_call_chain+0xcb/0x160 kernel/notifier.c:391 call_netdevice_notifiers_extack net/core/dev.c:2074 [inline] call_netdevice_notifiers net/core/dev.c:2088 [inline] dev_close_many+0x29f/0x400 net/core/dev.c:1663 unregister_netdevice_many+0x481/0x19f0 net/core/dev.c:11136 ip_tunnel_delete_nets+0x320/0x370 net/ipv4/ip_tunnel.c:1137 ops_exit_list net/core/net_namespace.c:177 [inline] cleanup_net+0x791/0xba0 net/core/net_namespace.c:635 process_one_work+0x85f/0x1010 kernel/workqueue.c:2310 worker_thread+0xaa6/0x1290 kernel/workqueue.c:2457 kthread+0x436/0x520 kernel/kthread.c:334 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287 Second to last potentially related work creation: kasan_save_stack+0x35/0x60 mm/kasan/common.c:38 kasan_record_aux_stack+0xb8/0x100 mm/kasan/generic.c:348 __call_rcu kernel/rcu/tree.c:3011 [inline] call_rcu+0x189/0x950 kernel/rcu/tree.c:3091 free_fib_info net/ipv4/fib_semantics.c:255 [inline] fib_info_put include/net/ip_fib.h:579 [inline] fib_release_info+0x684/0x740 net/ipv4/fib_semantics.c:281 fib_table_delete+0xdf2/0x1000 net/ipv4/fib_trie.c:1747 fib_magic+0x301/0x3c0 net/ipv4/fib_frontend.c:1108 fib_del_ifaddr+0x1045/0x1440 net/ipv4/fib_frontend.c:1319 fib_inetaddr_event+0xb7/0x1c0 net/ipv4/fib_frontend.c:1450 notifier_call_chain kernel/notifier.c:83 [inline] blocking_notifier_call_chain+0x103/0x1b0 kernel/notifier.c:318 __inet_del_ifa+0x879/0x1020 net/ipv4/devinet.c:442 inet_del_ifa net/ipv4/devinet.c:479 [inline] inetdev_destroy net/ipv4/devinet.c:320 [inline] inetdev_event+0x5b6/0x1370 net/ipv4/devinet.c:1611 notifier_call_chain kernel/notifier.c:83 [inline] raw_notifier_call_chain+0xcb/0x160 kernel/notifier.c:391 call_netdevice_notifiers_extack net/core/dev.c:2074 [inline] call_netdevice_notifiers net/core/dev.c:2088 [inline] unregister_netdevice_many+0x1049/0x19f0 net/core/dev.c:11160 default_device_exit_batch+0x364/0x3c0 net/core/dev.c:11693 ops_exit_list net/core/net_namespace.c:177 [inline] cleanup_net+0x791/0xba0 net/core/net_namespace.c:635 process_one_work+0x85f/0x1010 kernel/workqueue.c:2310 worker_thread+0xaa6/0x1290 kernel/workqueue.c:2457 kthread+0x436/0x520 kernel/kthread.c:334 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:287 The buggy address belongs to the object at ffff88805c7dfa00 which belongs to the cache kmalloc-256 of size 256 The buggy address is located 148 bytes inside of 256-byte region [ffff88805c7dfa00, ffff88805c7dfb00) The buggy address belongs to the page: page:ffffea000171f780 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x5c7de head:ffffea000171f780 order:1 compound_mapcount:0 flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff) raw: 00fff00000010200 dead000000000100 dead000000000122 ffff888016c41b40 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 0x1d20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC|__GFP_HARDWALL), pid 6986, ts 236714581017, free_ts 236159858546 prep_new_page mm/page_alloc.c:2426 [inline] get_page_from_freelist+0x1bbd/0x1ca0 mm/page_alloc.c:4192 __alloc_pages+0x1ee/0x480 mm/page_alloc.c:5501 alloc_slab_page mm/slub.c:1780 [inline] allocate_slab mm/slub.c:1917 [inline] new_slab+0xc0/0x4b0 mm/slub.c:1980 ___slab_alloc+0x80a/0xdd0 mm/slub.c:3013 __slab_alloc mm/slub.c:3100 [inline] slab_alloc_node mm/slub.c:3191 [inline] slab_alloc mm/slub.c:3233 [inline] __kmalloc+0x1cd/0x330 mm/slub.c:4408 kmalloc include/linux/slab.h:612 [inline] kzalloc include/linux/slab.h:738 [inline] new_dir fs/proc/proc_sysctl.c:959 [inline] get_subdir fs/proc/proc_sysctl.c:1004 [inline] __register_sysctl_table+0xa1f/0x1230 fs/proc/proc_sysctl.c:1353 neigh_sysctl_register+0x9b0/0xa90 net/core/neighbour.c:3718 devinet_sysctl_register+0xa8/0x1f0 net/ipv4/devinet.c:2640 inetdev_init+0x28c/0x4d0 net/ipv4/devinet.c:277 inetdev_event+0x26f/0x1370 net/ipv4/devinet.c:1543 notifier_call_chain kernel/notifier.c:83 [inline] raw_notifier_call_chain+0xcb/0x160 kernel/notifier.c:391 call_netdevice_notifiers_extack net/core/dev.c:2074 [inline] call_netdevice_notifiers net/core/dev.c:2088 [inline] register_netdevice+0x12a6/0x1710 net/core/dev.c:10454 __ip_tunnel_create+0x2c7/0x390 net/ipv4/ip_tunnel.c:267 ip_tunnel_init_net+0x246/0x6f0 net/ipv4/ip_tunnel.c:1084 ops_init+0x357/0x600 net/core/net_namespace.c:138 setup_net+0x39e/0xa10 net/core/net_namespace.c:333 page last free stack trace: reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1340 [inline] free_pcp_prepare mm/page_alloc.c:1391 [inline] free_unref_page_prepare+0x637/0x6c0 mm/page_alloc.c:3317 free_unref_page+0x8f/0x2a0 mm/page_alloc.c:3396 free_slab mm/slub.c:2020 [inline] discard_slab mm/slub.c:2026 [inline] __unfreeze_partials+0x1a5/0x200 mm/slub.c:2512 put_cpu_partial+0x12d/0x190 mm/slub.c:2592 qlist_free_all+0x35/0x90 mm/kasan/quarantine.c:176 kasan_quarantine_reduce+0x150/0x160 mm/kasan/quarantine.c:283 __kasan_slab_alloc+0x2f/0xd0 mm/kasan/common.c:444 kasan_slab_alloc include/linux/kasan.h:254 [inline] slab_post_alloc_hook+0x4c/0x380 mm/slab.h:519 slab_alloc_node mm/slub.c:3225 [inline] slab_alloc mm/slub.c:3233 [inline] kmem_cache_alloc+0x100/0x290 mm/slub.c:3238 vm_area_dup+0x1e/0xb0 kernel/fork.c:358 __split_vma+0xb1/0x410 mm/mmap.c:2730 __do_munmap+0x3fe/0xdf0 mm/mmap.c:2865 do_munmap mm/mmap.c:2910 [inline] munmap_vma_range mm/mmap.c:603 [inline] __mmap_region mm/mmap.c:1757 [inline] mmap_region+0x8b4/0x1650 mm/mmap.c:2933 do_mmap+0x819/0xe90 mm/mmap.c:1586 vm_mmap_pgoff+0x1c1/0x2d0 mm/util.c:551 ksys_mmap_pgoff+0x54b/0x790 mm/mmap.c:1635 Memory state around the buggy address: ffff88805c7df980: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff88805c7dfa00: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff88805c7dfa80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88805c7dfb00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff88805c7dfb80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ==================================================================