================================================================== BUG: KASAN: use-after-free in jfs_lazycommit+0x776/0xa90 fs/jfs/jfs_txnmgr.c:2736 Read of size 4 at addr ffff88802820d694 by task jfsCommit/107 CPU: 1 PID: 107 Comm: jfsCommit Not tainted syzkaller #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026 Call Trace: dump_stack_lvl+0x188/0x24e 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 jfs_lazycommit+0x776/0xa90 fs/jfs/jfs_txnmgr.c:2736 kthread+0x29d/0x330 kernel/kthread.c:376 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295 Allocated by task 4939: kasan_save_stack mm/kasan/common.c:46 [inline] kasan_set_track+0x4b/0x70 mm/kasan/common.c:53 ____kasan_kmalloc mm/kasan/common.c:375 [inline] __kasan_kmalloc+0x8e/0xa0 mm/kasan/common.c:384 kmalloc include/linux/slab.h:563 [inline] kzalloc include/linux/slab.h:699 [inline] jfs_fill_super+0xd8/0xab0 fs/jfs/super.c:495 mount_bdev+0x28a/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+0x247/0xa40 fs/namespace.c:3078 do_mount fs/namespace.c:3421 [inline] __do_sys_mount fs/namespace.c:3629 [inline] __se_sys_mount+0x2e3/0x3d0 fs/namespace.c:3606 do_syscall_x64 arch/x86/entry/common.c:46 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:76 entry_SYSCALL_64_after_hwframe+0x68/0xd2 Freed by task 4272: kasan_save_stack mm/kasan/common.c:46 [inline] kasan_set_track+0x4b/0x70 mm/kasan/common.c:53 kasan_save_free_info+0x27/0x40 mm/kasan/generic.c:516 ____kasan_slab_free+0x126/0x1f0 mm/kasan/common.c:237 kasan_slab_free include/linux/kasan.h:177 [inline] slab_free_hook mm/slub.c:1729 [inline] slab_free_freelist_hook+0x133/0x1b0 mm/slub.c:1755 slab_free mm/slub.c:3687 [inline] __kmem_cache_free+0xb6/0x200 mm/slub.c:3700 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+0x471/0x4f0 fs/namespace.c:1191 task_work_run+0x1d0/0x260 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+0xee/0x180 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:82 entry_SYSCALL_64_after_hwframe+0x68/0xd2 Last potentially related work creation: kasan_save_stack+0x3a/0x60 mm/kasan/common.c:46 __kasan_record_aux_stack+0xb2/0xc0 mm/kasan/generic.c:486 kvfree_call_rcu+0x103/0x890 kernel/rcu/tree.c:3405 tcp_cleanup_ulp+0x6e/0xe0 net/ipv4/tcp_ulp.c:124 tcp_v4_destroy_sock+0x191/0x760 net/ipv4/tcp_ipv4.c:2271 inet_csk_destroy_sock+0x15c/0x350 net/ipv4/inet_connection_sock.c:1229 __tcp_close+0xb04/0xdd0 net/ipv4/tcp.c:3070 __mptcp_close_ssk+0x354/0xde0 net/mptcp/protocol.c:2548 mptcp_destroy_common+0x115/0x4d0 net/mptcp/protocol.c:3526 mptcp_destroy+0x99/0x100 net/mptcp/protocol.c:3553 __mptcp_destroy_sock+0xde/0x330 net/mptcp/protocol.c:3112 __mptcp_close+0x59a/0x900 net/mptcp/protocol.c:3222 mptcp_close+0x24/0x120 net/mptcp/protocol.c:3237 inet_release+0x139/0x180 net/ipv4/af_inet.c:430 __sock_release net/socket.c:654 [inline] sock_close+0xbf/0x210 net/socket.c:1400 __fput+0x20a/0x8b0 fs/file_table.c:320 task_work_run+0x1d0/0x260 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+0xee/0x180 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:82 entry_SYSCALL_64_after_hwframe+0x68/0xd2 Second to last potentially related work creation: kasan_save_stack+0x3a/0x60 mm/kasan/common.c:46 __kasan_record_aux_stack+0xb2/0xc0 mm/kasan/generic.c:486 kvfree_call_rcu+0x103/0x890 kernel/rcu/tree.c:3405 drop_sysctl_table+0x359/0x4e0 fs/proc/proc_sysctl.c:1731 drop_sysctl_table+0x348/0x4e0 fs/proc/proc_sysctl.c:1734 unregister_sysctl_table+0x85/0x130 fs/proc/proc_sysctl.c:1769 neigh_sysctl_unregister+0x74/0x90 net/core/neighbour.c:3885 addrconf_sysctl_unregister net/ipv6/addrconf.c:7209 [inline] addrconf_notify+0x6bd/0xf60 net/ipv6/addrconf.c:3727 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:2052 [inline] call_netdevice_notifiers net/core/dev.c:2066 [inline] dev_change_name+0x676/0x910 net/core/dev.c:1295 do_setlink+0x967/0x29c0 net/core/rtnetlink.c:2817 __rtnl_newlink net/core/rtnetlink.c:3614 [inline] rtnl_newlink+0x16e4/0x1f90 net/core/rtnetlink.c:3661 rtnetlink_rcv_msg+0x863/0xfb0 net/core/rtnetlink.c:6158 netlink_rcv_skb+0x1ef/0x440 net/netlink/af_netlink.c:2516 netlink_unicast_kernel net/netlink/af_netlink.c:1318 [inline] netlink_unicast+0x7ad/0x920 net/netlink/af_netlink.c:1344 netlink_sendmsg+0x8ad/0xbd0 net/netlink/af_netlink.c:1877 sock_sendmsg_nosec net/socket.c:718 [inline] __sock_sendmsg net/socket.c:730 [inline] __sys_sendto+0x497/0x650 net/socket.c:2153 __do_sys_sendto net/socket.c:2165 [inline] __se_sys_sendto net/socket.c:2161 [inline] __x64_sys_sendto+0xda/0xf0 net/socket.c:2161 do_syscall_x64 arch/x86/entry/common.c:46 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:76 entry_SYSCALL_64_after_hwframe+0x68/0xd2 The buggy address belongs to the object at ffff88802820d600 which belongs to the cache kmalloc-256 of size 256 The buggy address is located 148 bytes inside of 256-byte region [ffff88802820d600, ffff88802820d700) The buggy address belongs to the physical page: page:ffffea0000a08300 refcount:1 mapcount:0 mapping:0000000000000000 index:0xffff88802820d400 pfn:0x2820c head:ffffea0000a08300 order:1 compound_mapcount:0 compound_pincount:0 flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff) raw: 00fff00000010200 ffffea0000bd0400 dead000000000005 ffff888017441b40 raw: ffff88802820d400 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 4287, tgid 4287 (syz-executor), ts 80704883052, free_ts 80671395601 set_page_owner include/linux/page_owner.h:31 [inline] post_alloc_hook+0x173/0x1a0 mm/page_alloc.c:2560 prep_new_page mm/page_alloc.c:2567 [inline] get_page_from_freelist+0x206b/0x2180 mm/page_alloc.c:4358 __alloc_pages+0x1ec/0x4f0 mm/page_alloc.c:5658 alloc_slab_page+0x5d/0x180 mm/slub.c:1799 allocate_slab mm/slub.c:1944 [inline] new_slab+0x87/0x2d0 mm/slub.c:1997 ___slab_alloc+0xbc5/0x1240 mm/slub.c:3154 __slab_alloc mm/slub.c:3240 [inline] slab_alloc_node mm/slub.c:3325 [inline] __kmem_cache_alloc_node+0x126/0x270 mm/slub.c:3398 __do_kmalloc_node mm/slab_common.c:935 [inline] __kmalloc+0xa3/0x240 mm/slab_common.c:949 kmalloc include/linux/slab.h:568 [inline] kzalloc include/linux/slab.h:699 [inline] fib_create_info+0xa78/0x2370 net/ipv4/fib_semantics.c:1459 fib_table_insert+0xc2/0x1af0 net/ipv4/fib_trie.c:1217 fib_magic+0x2ca/0x3b0 net/ipv4/fib_frontend.c:1118 fib_add_ifaddr+0x135/0x5c0 net/ipv4/fib_frontend.c:1140 fib_netdev_event+0x361/0x470 net/ipv4/fib_frontend.c:1500 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:2052 [inline] call_netdevice_notifiers net/core/dev.c:2066 [inline] __dev_notify_flags+0x1a7/0x310 net/core/dev.c:8715 dev_change_flags+0xda/0x1a0 net/core/dev.c:8753 page last free stack trace: reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1487 [inline] free_pcp_prepare mm/page_alloc.c:1537 [inline] free_unref_page_prepare+0x8e5/0x9e0 mm/page_alloc.c:3414 free_unref_page+0x2e/0x3f0 mm/page_alloc.c:3509 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:306 kasan_slab_alloc include/linux/kasan.h:201 [inline] slab_post_alloc_hook+0x4b/0x490 mm/slab.h:737 slab_alloc_node mm/slub.c:3359 [inline] slab_alloc mm/slub.c:3367 [inline] __kmem_cache_alloc_lru mm/slub.c:3374 [inline] kmem_cache_alloc_lru+0x182/0x2e0 mm/slub.c:3390 alloc_inode_sb include/linux/fs.h:3245 [inline] sock_alloc_inode+0x24/0xc0 net/socket.c:306 alloc_inode fs/inode.c:261 [inline] new_inode_pseudo+0x5f/0x1c0 fs/inode.c:1063 sock_alloc net/socket.c:631 [inline] __sock_create+0x129/0x940 net/socket.c:1514 sock_create net/socket.c:1606 [inline] __sys_socket_create net/socket.c:1643 [inline] __sys_socket+0xc4/0x190 net/socket.c:1671 __do_sys_socket net/socket.c:1684 [inline] __se_sys_socket net/socket.c:1682 [inline] __x64_sys_socket+0x76/0x80 net/socket.c:1682 do_syscall_x64 arch/x86/entry/common.c:46 [inline] do_syscall_64+0x4c/0xa0 arch/x86/entry/common.c:76 entry_SYSCALL_64_after_hwframe+0x68/0xd2 Memory state around the buggy address: ffff88802820d580: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff88802820d600: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff88802820d680: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88802820d700: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff88802820d780: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ==================================================================