================================================================== BUG: KASAN: slab-use-after-free in jfs_lazycommit+0x6e1/0 BUG: KASAN: slab-use-after-free in jfs_lazycommit+0x6e1/0xa20 fs/jfs/jfs_txnmgr.c:2738 Read of size 4 at addr ffff88803e561c94 by task jfsCommit/131 CPU: 1 UID: 0 PID: 131 Comm: jfsCommit Not tainted syzkaller #0 PREEMPT_{RT,(full)} Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 09/16/2026 Call Trace: dump_stack_lvl+0xe8/0x150 lib/dump_stack.c:120 print_address_description+0x55/0x1e0 mm/kasan/report.c:378 print_report+0x58/0x70 mm/kasan/report.c:482 kasan_report+0x117/0x150 mm/kasan/report.c:595 jfs_lazycommit+0x6e1/0xa20 fs/jfs/jfs_txnmgr.c:2738 kthread+0x38b/0x470 kernel/kthread.c:436 ret_from_fork+0x514/0xb70 arch/x86/kernel/process.c:158 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 Allocated by task 18444: kasan_save_stack mm/kasan/common.c:57 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:78 poison_kmalloc_redzone mm/kasan/common.c:409 [inline] __kasan_kmalloc+0x93/0xb0 mm/kasan/common.c:426 kasan_kmalloc include/linux/kasan.h:263 [inline] __kmalloc_cache_noprof+0x3d5/0x680 mm/slub.c:5563 _kmalloc_noprof include/linux/slab.h:991 [inline] _kzalloc_noprof include/linux/slab.h:1312 [inline] jfs_fill_super+0xc2/0xda0 fs/jfs/super.c:452 get_tree_bdev_flags+0x430/0x4f0 fs/super.c:1872 vfs_get_tree+0x92/0x2a0 fs/super.c:1932 fc_mount fs/namespace.c:1278 [inline] do_new_mount_fc fs/namespace.c:3885 [inline] do_new_mount+0x325/0xb00 fs/namespace.c:3961 do_mount fs/namespace.c:4325 [inline] __do_sys_mount fs/namespace.c:4543 [inline] __se_sys_mount+0x31d/0x420 fs/namespace.c:4520 do_syscall_x64 arch/x86/entry/syscall_64.c:61 [inline] do_syscall_64+0x166/0x520 arch/x86/entry/syscall_64.c:84 entry_SYSCALL_64_after_hwframe+0x77/0x7f Freed by task 17755: kasan_save_stack mm/kasan/common.c:57 [inline] kasan_save_track+0x3e/0x80 mm/kasan/common.c:78 kasan_save_free_info+0x40/0x50 mm/kasan/generic.c:584 poison_slab_object mm/kasan/common.c:264 [inline] __kasan_slab_free+0x5c/0x80 mm/kasan/common.c:296 kasan_slab_free include/linux/kasan.h:235 [inline] slab_free_hook mm/slub.c:2748 [inline] slab_free mm/slub.c:6509 [inline] kfree+0x1c5/0x6d0 mm/slub.c:6802 generic_shutdown_super+0x13d/0x2d0 fs/super.c:751 kill_block_super+0x44/0xa0 fs/super.c:1903 deactivate_locked_super+0xbe/0x110 fs/super.c:586 cleanup_mnt+0x204/0x2a0 fs/namespace.c:1392 task_work_run+0x1d9/0x270 kernel/task_work.c:233 resume_user_mode_work include/linux/resume_user_mode.h:50 [inline] __exit_to_user_mode_loop kernel/entry/common.c:70 [inline] exit_to_user_mode_loop+0x204/0x770 kernel/entry/common.c:101 __exit_to_user_mode_prepare include/linux/irq-entry-common.h:207 [inline] syscall_exit_to_user_mode_prepare include/linux/irq-entry-common.h:230 [inline] syscall_exit_to_user_mode include/linux/entry-common.h:343 [inline] do_syscall_64+0x328/0x520 arch/x86/entry/syscall_64.c:89 entry_SYSCALL_64_after_hwframe+0x77/0x7f The buggy address belongs to the object at ffff88803e561c00 which belongs to the cache kmalloc-256 of size 256 The buggy address is located 148 bytes inside of freed 256-byte region [ffff88803e561c00, ffff88803e561d00) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x3e560 head: order:1 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0 flags: 0x80000000000040(head|node=0|zone=1) page_type: f5(slab) raw: 0080000000000040 ffff88813ffbeb40 dead000000000100 dead000000000122 raw: 0000000000000000 0000000000100010 00000000f5000000 0000000000000000 head: 0080000000000040 ffff88813ffbeb40 dead000000000100 dead000000000122 head: 0000000000000000 0000000000100010 00000000f5000000 0000000000000000 head: 0080000000000001 ffffffffffffff81 00000000ffffffff 00000000ffffffff head: 0000000000000000 0000000000000000 00000000ffffffff 0000000000000002 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 5603, tgid 5603 (syz-executor), ts 94077282970 set_page_owner include/linux/page_owner.h:33 [inline] post_alloc_hook+0x1f9/0x250 mm/page_alloc.c:1871 prep_new_page mm/page_alloc.c:1879 [inline] get_page_from_freelist+0x2591/0x2600 mm/page_alloc.c:3943 __alloc_frozen_pages_noprof+0x230/0x5c0 mm/page_alloc.c:5436 alloc_slab_page mm/slub.c:3347 [inline] allocate_slab+0x7d/0x620 mm/slub.c:3462 new_slab mm/slub.c:3513 [inline] refill_objects+0x2d8/0x350 mm/slub.c:7418 refill_sheaf mm/slub.c:2885 [inline] __pcs_replace_empty_main+0x339/0x690 mm/slub.c:4774 alloc_from_pcs mm/slub.c:4850 [inline] slab_alloc_node mm/slub.c:4984 [inline] __do_kmalloc_node mm/slub.c:5413 [inline] __kmalloc_noprof+0x54b/0x790 mm/slub.c:5439 _kmalloc_noprof include/linux/slab.h:995 [inline] _kzalloc_noprof include/linux/slab.h:1312 [inline] new_dir fs/proc/proc_sysctl.c:965 [inline] get_subdir fs/proc/proc_sysctl.c:1009 [inline] sysctl_mkdir_p fs/proc/proc_sysctl.c:1319 [inline] __register_sysctl_table+0xc02/0x1370 fs/proc/proc_sysctl.c:1394 neigh_sysctl_register+0x9b1/0xa90 net/core/neighbour.c:3932 addrconf_sysctl_register+0xb3/0x1c0 net/ipv6/addrconf.c:7396 ipv6_add_dev+0xd64/0x1400 net/ipv6/addrconf.c:460 addrconf_notify+0x771/0x1050 net/ipv6/addrconf.c:3686 notifier_call_chain+0x1a5/0x3d0 kernel/notifier.c:85 call_netdevice_notifiers_extack net/core/dev.c:2313 [inline] call_netdevice_notifiers net/core/dev.c:2327 [inline] register_netdevice+0x18c0/0x1ed0 net/core/dev.c:11587 veth_newlink+0x4d7/0xdd0 drivers/net/veth.c:1873 rtnl_newlink_create+0x305/0x7b0 net/core/rtnetlink.c:3974 page last free pid 5601 tgid 5601 ts 93015894099 stack trace: reset_page_owner include/linux/page_owner.h:26 [inline] __free_pages_prepare mm/page_alloc.c:1418 [inline] __free_frozen_pages+0xf8e/0x1070 mm/page_alloc.c:2962 __slab_free+0x250/0x2a0 mm/slub.c:5823 qlink_free mm/kasan/quarantine.c:163 [inline] qlist_free_all+0x99/0x100 mm/kasan/quarantine.c:179 kasan_quarantine_reduce+0x148/0x160 mm/kasan/quarantine.c:286 __kasan_slab_alloc+0x22/0x80 mm/kasan/common.c:361 kasan_slab_alloc include/linux/kasan.h:253 [inline] slab_post_alloc_hook mm/slub.c:4683 [inline] slab_alloc_node mm/slub.c:4996 [inline] __kmalloc_cache_noprof+0x353/0x680 mm/slub.c:5559 _kmalloc_noprof include/linux/slab.h:991 [inline] __netdev_adjacent_dev_insert+0x16f/0xa10 net/core/dev.c:8848 __netdev_adjacent_dev_link_lists net/core/dev.c:8940 [inline] __netdev_adjacent_dev_link_neighbour net/core/dev.c:8969 [inline] __netdev_upper_dev_link+0xa33/0xc90 net/core/dev.c:9029 netdev_upper_dev_link+0xb0/0x100 net/core/dev.c:9075 macsec_newlink+0x114e/0x18c0 drivers/net/macsec.c:4253 rtnl_newlink_create+0x305/0x7b0 net/core/rtnetlink.c:3974 __rtnl_newlink net/core/rtnetlink.c:4103 [inline] rtnl_newlink+0x166d/0x1c30 net/core/rtnetlink.c:4220 rtnetlink_rcv_msg+0x802/0xc00 net/core/rtnetlink.c:7137 netlink_rcv_skb+0x226/0x4a0 net/netlink/af_netlink.c:2579 netlink_unicast_kernel net/netlink/af_netlink.c:1338 [inline] netlink_unicast+0x90c/0xac0 net/netlink/af_netlink.c:1364 netlink_sendmsg+0x813/0xb40 net/netlink/af_netlink.c:1923 Memory state around the buggy address: ffff88803e561b80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff88803e561c00: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff88803e561c80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88803e561d00: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff88803e561d80: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ==================================================================