================================================================== BUG: KASAN: use-after-free in jfs_lazycommit+0x74d/0xa70 fs/jfs/jfs_txnmgr.c:2736 Read of size 4 at addr ffff88802768c694 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 04/18/2026 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+0x74d/0xa70 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 6312: 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+0xd8/0xad0 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: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 4268: kasan_save_stack mm/kasan/common.c:46 [inline] kasan_set_track+0x4b/0x70 mm/kasan/common.c:53 kasan_save_free_info+0x2d/0x50 mm/kasan/generic.c:516 ____kasan_slab_free+0x126/0x1e0 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+0x131/0x1a0 mm/slub.c:1755 slab_free mm/slub.c:3687 [inline] __kmem_cache_free+0xb6/0x1f0 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+0x42c/0x4b0 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+0x103/0x870 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 mpls_dev_sysctl_unregister+0x8b/0xc0 net/mpls/af_mpls.c:1445 mpls_dev_notify+0x555/0x760 net/mpls/af_mpls.c:1657 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] unregister_netdevice_many_notify+0x10ac/0x19c0 net/core/dev.c:11023 rtnl_newlink_create net/core/rtnetlink.c:3458 [inline] __rtnl_newlink net/core/rtnetlink.c:3647 [inline] rtnl_newlink+0x1cbf/0x20a0 net/core/rtnetlink.c:3660 rtnetlink_rcv_msg+0x87c/0xfc0 net/core/rtnetlink.c:6157 netlink_rcv_skb+0x1fb/0x450 net/netlink/af_netlink.c:2511 netlink_unicast_kernel net/netlink/af_netlink.c:1318 [inline] netlink_unicast+0x74d/0x8d0 net/netlink/af_netlink.c:1344 netlink_sendmsg+0x8ad/0xbd0 net/netlink/af_netlink.c:1872 sock_sendmsg_nosec net/socket.c:718 [inline] __sock_sendmsg net/socket.c:730 [inline] ____sys_sendmsg+0x5be/0x970 net/socket.c:2518 ___sys_sendmsg+0x2a2/0x360 net/socket.c:2572 __sys_sendmsg net/socket.c:2601 [inline] __do_sys_sendmsg net/socket.c:2610 [inline] __se_sys_sendmsg+0x1bb/0x2a0 net/socket.c:2608 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 ffff88802768c600 which belongs to the cache kmalloc-256 of size 256 The buggy address is located 148 bytes inside of 256-byte region [ffff88802768c600, ffff88802768c700) The buggy address belongs to the physical page: page:ffffea00009da300 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x2768c head:ffffea00009da300 order:1 compound_mapcount:0 compound_pincount:0 flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff) raw: 00fff00000010200 ffffea000078e200 dead000000000007 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 0x152a20(GFP_ATOMIC|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_HARDWALL), pid 4393, tgid 4388 (syz.0.12), ts 80320138082, free_ts 78677870527 set_page_owner include/linux/page_owner.h:31 [inline] post_alloc_hook+0x173/0x1a0 mm/page_alloc.c:2559 prep_new_page mm/page_alloc.c:2566 [inline] get_page_from_freelist+0x1a1e/0x1ab0 mm/page_alloc.c:4357 __alloc_pages+0x1ec/0x4f0 mm/page_alloc.c:5657 alloc_slab_page+0x5d/0x160 mm/slub.c:1799 allocate_slab mm/slub.c:1944 [inline] new_slab+0x87/0x2c0 mm/slub.c:1997 ___slab_alloc+0xbc6/0x1240 mm/slub.c:3154 __slab_alloc mm/slub.c:3240 [inline] slab_alloc_node mm/slub.c:3325 [inline] __kmem_cache_alloc_node+0x1a0/0x260 mm/slub.c:3398 __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] hash_ipportip6_add+0x183a/0x2320 net/netfilter/ipset/ip_set_hash_gen.h:937 hash_ipportip6_uadt+0x75e/0xa20 net/netfilter/ipset/ip_set_hash_ipportip.c:346 call_ad+0x389/0xb10 net/netfilter/ipset/ip_set_core.c:1753 ip_set_ad+0x816/0x9c0 net/netfilter/ipset/ip_set_core.c:1843 nfnetlink_rcv_msg+0xbec/0x12b0 net/netfilter/nfnetlink.c:302 netlink_rcv_skb+0x1fb/0x450 net/netlink/af_netlink.c:2511 nfnetlink_rcv+0x2b0/0x2480 net/netfilter/nfnetlink.c:659 netlink_unicast_kernel net/netlink/af_netlink.c:1318 [inline] netlink_unicast+0x74d/0x8d0 net/netlink/af_netlink.c:1344 page last free stack trace: reset_page_owner include/linux/page_owner.h:24 [inline] free_pages_prepare mm/page_alloc.c:1486 [inline] free_pcp_prepare mm/page_alloc.c:1536 [inline] free_unref_page_prepare+0x8b4/0x9a0 mm/page_alloc.c:3413 free_unref_page+0x2e/0x3f0 mm/page_alloc.c:3508 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/0x480 mm/slab.h:737 slab_alloc_node mm/slub.c:3359 [inline] __kmem_cache_alloc_node+0x140/0x260 mm/slub.c:3398 __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] tomoyo_encode2 security/tomoyo/realpath.c:45 [inline] tomoyo_encode+0x27e/0x540 security/tomoyo/realpath.c:80 tomoyo_realpath_from_path+0x58e/0x5d0 security/tomoyo/realpath.c:283 tomoyo_get_realpath security/tomoyo/file.c:151 [inline] tomoyo_path_perm+0x26f/0x610 security/tomoyo/file.c:822 security_inode_getattr+0xcf/0x120 security/security.c:1362 vfs_getattr+0x26/0x3a0 fs/stat.c:158 vfs_fstat fs/stat.c:183 [inline] __do_sys_newfstat fs/stat.c:447 [inline] __se_sys_newfstat fs/stat.c:444 [inline] __x64_sys_newfstat+0x13d/0x220 fs/stat.c:444 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: ffff88802768c580: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff88802768c600: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff88802768c680: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88802768c700: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff88802768c780: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ==================================================================