================================================================== BUG: KASAN: slab-use-after-free in jfs_lazycommit+0x751/0xa70 fs/jfs/jfs_txnmgr.c:2736 Read of size 4 at addr ffff88807e898494 by task jfsCommit/112 CPU: 0 PID: 112 Comm: jfsCommit Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/25/2025 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 7287: 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 5786: 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 __addrconf_sysctl_unregister net/ipv6/addrconf.c:7240 [inline] addrconf_sysctl_unregister net/ipv6/addrconf.c:7268 [inline] addrconf_notify+0x2d3/0x1010 net/ipv6/addrconf.c:3772 notifier_call_chain+0x197/0x380 kernel/notifier.c:93 call_netdevice_notifiers_extack net/core/dev.c:2090 [inline] call_netdevice_notifiers net/core/dev.c:2104 [inline] dev_change_name+0x5e7/0x8c0 net/core/dev.c:1326 do_setlink+0x9fc/0x4130 net/core/rtnetlink.c:2885 __rtnl_newlink net/core/rtnetlink.c:3703 [inline] rtnl_newlink+0x17da/0x20a0 net/core/rtnetlink.c:3750 rtnetlink_rcv_msg+0x869/0xfa0 net/core/rtnetlink.c:6472 netlink_rcv_skb+0x241/0x4d0 net/netlink/af_netlink.c:2545 netlink_unicast_kernel net/netlink/af_netlink.c:1320 [inline] netlink_unicast+0x751/0x8d0 net/netlink/af_netlink.c:1346 netlink_sendmsg+0x8d0/0xbf0 net/netlink/af_netlink.c:1894 sock_sendmsg_nosec net/socket.c:730 [inline] __sock_sendmsg net/socket.c:745 [inline] __sys_sendto+0x4a9/0x6b0 net/socket.c:2200 __do_sys_sendto net/socket.c:2212 [inline] __se_sys_sendto net/socket.c:2208 [inline] __x64_sys_sendto+0xde/0xf0 net/socket.c:2208 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 The buggy address belongs to the object at ffff88807e898400 which belongs to the cache kmalloc-256 of size 256 The buggy address is located 148 bytes inside of freed 256-byte region [ffff88807e898400, ffff88807e898500) The buggy address belongs to the physical page: page:ffffea0001fa2600 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x7e898 head:ffffea0001fa2600 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 ffffea0000af5e80 dead000000000004 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 5774, tgid 5774 (syz-executor), ts 91743263204, free_ts 91668837388 set_page_owner include/linux/page_owner.h:31 [inline] post_alloc_hook+0x1c1/0x200 mm/page_alloc.c:1554 prep_new_page mm/page_alloc.c:1561 [inline] get_page_from_freelist+0x1951/0x19e0 mm/page_alloc.c:3191 __alloc_pages+0x1f0/0x460 mm/page_alloc.c:4457 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+0x3fb/0x5e0 net/ipv4/fib_frontend.c:1162 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:2090 [inline] call_netdevice_notifiers net/core/dev.c:2104 [inline] __dev_notify_flags+0x1aa/0x310 net/core/dev.c:8755 dev_change_flags+0xe8/0x1a0 net/core/dev.c:8793 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+0x7b2/0x8c0 mm/page_alloc.c:2336 free_unref_page+0x32/0x2e0 mm/page_alloc.c:2429 __slab_free+0x35a/0x400 mm/slub.c:3736 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_lru+0x111/0x2d0 mm/slub.c:3526 alloc_inode_sb include/linux/fs.h:2946 [inline] sock_alloc_inode+0x28/0xc0 net/socket.c:308 alloc_inode fs/inode.c:261 [inline] new_inode_pseudo+0x63/0x1d0 fs/inode.c:1049 sock_alloc net/socket.c:634 [inline] __sock_create+0x12d/0x940 net/socket.c:1534 sock_create net/socket.c:1626 [inline] __sys_socket_create net/socket.c:1663 [inline] __sys_socket+0xd7/0x1a0 net/socket.c:1714 __do_sys_socket net/socket.c:1728 [inline] __se_sys_socket net/socket.c:1726 [inline] __x64_sys_socket+0x7a/0x90 net/socket.c:1726 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 Memory state around the buggy address: ffff88807e898380: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff88807e898400: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff88807e898480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88807e898500: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff88807e898580: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ==================================================================