================================================================== BUG: KASAN: slab-use-after-free in jfs_lazycommit+0x751/0xa70 fs/jfs/jfs_txnmgr.c:2736 Read of size 4 at addr ffff88802f887294 by task jfsCommit/111 CPU: 0 PID: 111 Comm: jfsCommit Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/24/2026 Call Trace: dump_stack_lvl+0x18c/0x250 lib/dump_stack.c:106 print_address_description mm/kasan/report.c:364 [inline] print_report+0xa8/0x210 mm/kasan/report.c:468 kasan_report+0x117/0x150 mm/kasan/report.c:581 jfs_lazycommit+0x751/0xa70 fs/jfs/jfs_txnmgr.c:2736 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 7044: kasan_save_stack mm/kasan/common.c:46 [inline] kasan_set_track+0x4e/0x70 mm/kasan/common.c:53 ____kasan_kmalloc mm/kasan/common.c:375 [inline] __kasan_kmalloc+0x8f/0xa0 mm/kasan/common.c:384 kmalloc include/linux/slab.h:600 [inline] kzalloc include/linux/slab.h:721 [inline] jfs_fill_super+0xdc/0xad0 fs/jfs/super.c:495 mount_bdev+0x221/0x2d0 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:3386 do_mount fs/namespace.c:3726 [inline] __do_sys_mount fs/namespace.c:3935 [inline] __se_sys_mount+0x2e7/0x3d0 fs/namespace.c:3912 do_syscall_x64 arch/x86/entry/common.c:46 [inline] do_syscall_64+0x55/0xa0 arch/x86/entry/common.c:76 entry_SYSCALL_64_after_hwframe+0x68/0xd2 Freed by task 5767: kasan_save_stack mm/kasan/common.c:46 [inline] kasan_set_track+0x4e/0x70 mm/kasan/common.c:53 kasan_save_free_info+0x2e/0x50 mm/kasan/generic.c:522 ____kasan_slab_free+0x126/0x1e0 mm/kasan/common.c:237 kasan_slab_free include/linux/kasan.h:164 [inline] slab_free_hook mm/slub.c:1811 [inline] slab_free_freelist_hook+0x130/0x1a0 mm/slub.c:1837 slab_free mm/slub.c:3830 [inline] __kmem_cache_free+0xba/0x1e0 mm/slub.c:3843 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+0x43b/0x4d0 fs/namespace.c:1259 task_work_run+0x1d4/0x260 kernel/task_work.c:245 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+0xee/0x180 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+0x61/0xa0 arch/x86/entry/common.c:82 entry_SYSCALL_64_after_hwframe+0x68/0xd2 Last potentially related work creation: kasan_save_stack+0x3e/0x60 mm/kasan/common.c:46 __kasan_record_aux_stack+0xaf/0xc0 mm/kasan/generic.c:492 kvfree_call_rcu+0xee/0x790 kernel/rcu/tree.c:3452 drop_sysctl_table+0x394/0x540 fs/proc/proc_sysctl.c:1515 drop_sysctl_table+0x3ab/0x540 fs/proc/proc_sysctl.c:1518 unregister_sysctl_table+0x41/0x60 fs/proc/proc_sysctl.c:1536 neigh_sysctl_unregister+0x78/0xa0 net/core/neighbour.c:3891 addrconf_sysctl_unregister net/ipv6/addrconf.c:7270 [inline] addrconf_ifdown+0x15c1/0x18c0 net/ipv6/addrconf.c:3996 addrconf_notify+0x6c6/0x1010 net/ipv6/addrconf.c:-1 notifier_call_chain+0x197/0x380 kernel/notifier.c:93 call_netdevice_notifiers_extack net/core/dev.c:2077 [inline] call_netdevice_notifiers net/core/dev.c:2091 [inline] unregister_netdevice_many_notify+0x100d/0x1900 net/core/dev.c:11099 ip6_tnl_exit_batch_net+0x5db/0x630 net/ipv6/ip6_tunnel.c:2295 ops_exit_list net/core/net_namespace.c:178 [inline] cleanup_net+0x795/0xbb0 net/core/net_namespace.c:652 process_one_work kernel/workqueue.c:2634 [inline] process_scheduled_works+0xa5d/0x15d0 kernel/workqueue.c:2711 worker_thread+0xa55/0xfc0 kernel/workqueue.c:2792 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 Second to last potentially related work creation: kasan_save_stack+0x3e/0x60 mm/kasan/common.c:46 __kasan_record_aux_stack+0xaf/0xc0 mm/kasan/generic.c:492 kvfree_call_rcu+0xee/0x790 kernel/rcu/tree.c:3452 drop_sysctl_table+0x394/0x540 fs/proc/proc_sysctl.c:1515 drop_sysctl_table+0x3ab/0x540 fs/proc/proc_sysctl.c:1518 unregister_sysctl_table+0x41/0x60 fs/proc/proc_sysctl.c:1536 __devinet_sysctl_unregister net/ipv4/devinet.c:2656 [inline] devinet_sysctl_unregister net/ipv4/devinet.c:2684 [inline] inetdev_destroy net/ipv4/devinet.c:330 [inline] inetdev_event+0x79a/0x1630 net/ipv4/devinet.c:1636 notifier_call_chain+0x197/0x380 kernel/notifier.c:93 call_netdevice_notifiers_extack net/core/dev.c:2077 [inline] call_netdevice_notifiers net/core/dev.c:2091 [inline] unregister_netdevice_many_notify+0x100d/0x1900 net/core/dev.c:11099 unregister_netdevice_many net/core/dev.c:11155 [inline] default_device_exit_batch+0x9ee/0xa80 net/core/dev.c:11633 ops_exit_list net/core/net_namespace.c:178 [inline] cleanup_net+0x795/0xbb0 net/core/net_namespace.c:652 process_one_work kernel/workqueue.c:2634 [inline] process_scheduled_works+0xa5d/0x15d0 kernel/workqueue.c:2711 worker_thread+0xa55/0xfc0 kernel/workqueue.c:2792 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 ffff88802f887200 which belongs to the cache kmalloc-256 of size 256 The buggy address is located 148 bytes inside of freed 256-byte region [ffff88802f887200, ffff88802f887300) The buggy address belongs to the physical page: page:ffffea0000be2180 refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff88802f886c00 pfn:0x2f886 head:ffffea0000be2180 order:1 entire_mapcount:0 nr_pages_mapped:0 pincount:0 flags: 0xfff00000000840(slab|head|node=0|zone=1|lastcpupid=0x7ff) page_type: 0xffffffff() raw: 00fff00000000840 ffff888017c41b40 dead000000000100 dead000000000122 raw: ffff88802f886c00 000000008010000d 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 5767, tgid 5767 (syz-executor), ts 79959858465, free_ts 79955768329 set_page_owner include/linux/page_owner.h:31 [inline] post_alloc_hook+0x1c1/0x200 mm/page_alloc.c:1581 prep_new_page mm/page_alloc.c:1588 [inline] get_page_from_freelist+0x1951/0x19e0 mm/page_alloc.c:3220 __alloc_pages+0x1f0/0x460 mm/page_alloc.c:4486 alloc_slab_page+0x5d/0x160 mm/slub.c:1881 allocate_slab mm/slub.c:2028 [inline] new_slab+0x87/0x2d0 mm/slub.c:2081 ___slab_alloc+0xc5d/0x12f0 mm/slub.c:3253 __slab_alloc mm/slub.c:3339 [inline] __slab_alloc_node mm/slub.c:3392 [inline] slab_alloc_node mm/slub.c:3485 [inline] __kmem_cache_alloc_node+0x19e/0x250 mm/slub.c:3534 __do_kmalloc_node mm/slab_common.c:1006 [inline] __kmalloc+0xa4/0x230 mm/slab_common.c:1020 kmalloc include/linux/slab.h:604 [inline] kzalloc include/linux/slab.h:721 [inline] fib_create_info+0xa61/0x2460 net/ipv4/fib_semantics.c:1459 fib_table_insert+0xc6/0x1b20 net/ipv4/fib_trie.c:1217 fib_magic+0x2e5/0x3c0 net/ipv4/fib_frontend.c:1118 fib_add_ifaddr+0x144/0x5e0 net/ipv4/fib_frontend.c:1140 fib_netdev_event+0x389/0x490 net/ipv4/fib_frontend.c:1500 notifier_call_chain+0x197/0x380 kernel/notifier.c:93 call_netdevice_notifiers_extack net/core/dev.c:2077 [inline] call_netdevice_notifiers net/core/dev.c:2091 [inline] __dev_notify_flags+0x1aa/0x310 net/core/dev.c:8737 dev_change_flags+0xe8/0x1a0 net/core/dev.c:8775 page last free stack trace: reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1181 [inline] free_unref_page_prepare+0x7b2/0x8c0 mm/page_alloc.c:2365 free_unref_page+0x32/0x2e0 mm/page_alloc.c:2458 discard_slab mm/slub.c:2127 [inline] __unfreeze_partials+0x1cf/0x210 mm/slub.c:2667 put_cpu_partial+0x17c/0x250 mm/slub.c:2743 __slab_free+0x319/0x400 mm/slub.c:3700 qlink_free mm/kasan/quarantine.c:166 [inline] qlist_free_all+0x75/0xd0 mm/kasan/quarantine.c:185 kasan_quarantine_reduce+0x143/0x160 mm/kasan/quarantine.c:292 __kasan_slab_alloc+0x22/0x80 mm/kasan/common.c:306 kasan_slab_alloc include/linux/kasan.h:188 [inline] slab_post_alloc_hook+0x6e/0x4b0 mm/slab.h:767 slab_alloc_node mm/slub.c:3495 [inline] slab_alloc mm/slub.c:3503 [inline] __kmem_cache_alloc_lru mm/slub.c:3510 [inline] kmem_cache_alloc+0x11a/0x2d0 mm/slub.c:3519 kmem_cache_zalloc include/linux/slab.h:711 [inline] add+0xed/0x1ba0 drivers/net/wireguard/allowedips.c:190 wg_allowedips_insert_v6+0x13d/0x210 drivers/net/wireguard/allowedips.c:300 set_allowedip drivers/net/wireguard/netlink.c:349 [inline] set_peer drivers/net/wireguard/netlink.c:463 [inline] wg_set_device+0x153c/0x1f70 drivers/net/wireguard/netlink.c:592 genl_family_rcv_msg_doit+0x211/0x310 net/netlink/genetlink.c:971 genl_family_rcv_msg net/netlink/genetlink.c:1051 [inline] genl_rcv_msg+0x619/0x7a0 net/netlink/genetlink.c:1066 netlink_rcv_skb+0x241/0x4d0 net/netlink/af_netlink.c:2545 Memory state around the buggy address: ffff88802f887180: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff88802f887200: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff88802f887280: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88802f887300: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff88802f887380: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ==================================================================