... Log Wrap ... Log Wrap ... Log Wrap ... ================================================================== BUG: KASAN: slab-use-after-free in lmLogSync+0x9a5/0xa40 fs/jfs/jfs_logmgr.c:1003 Write of size 4 at addr ffff88807f47ba18 by task jfsCommit/117 CPU: 1 UID: 0 PID: 117 Comm: jfsCommit Tainted: G L syzkaller #0 PREEMPT(full) Tainted: [L]=SOFTLOCKUP Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026 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 lmLogSync+0x9a5/0xa40 fs/jfs/jfs_logmgr.c:1003 jfs_syncpt+0x7b/0x90 fs/jfs/jfs_logmgr.c:1039 txEnd+0x2e5/0x530 fs/jfs/jfs_txnmgr.c:551 txLazyCommit fs/jfs/jfs_txnmgr.c:2686 [inline] jfs_lazycommit+0x5d6/0xac0 fs/jfs/jfs_txnmgr.c:2735 kthread+0x389/0x470 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 25473: 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:398 [inline] __kasan_kmalloc+0x93/0xb0 mm/kasan/common.c:415 kasan_kmalloc include/linux/kasan.h:263 [inline] __kmalloc_cache_noprof+0x318/0x660 mm/slub.c:5420 kmalloc_noprof include/linux/slab.h:950 [inline] kzalloc_noprof include/linux/slab.h:1188 [inline] open_inline_log fs/jfs/jfs_logmgr.c:1157 [inline] lmLogOpen+0x2d1/0xf90 fs/jfs/jfs_logmgr.c:1067 jfs_mount_rw+0xf3/0x670 fs/jfs/jfs_mount.c:257 jfs_fill_super+0x772/0xd90 fs/jfs/super.c:532 get_tree_bdev_flags+0x430/0x4f0 fs/super.c:1694 vfs_get_tree+0x92/0x2a0 fs/super.c:1754 fc_mount fs/namespace.c:1193 [inline] do_new_mount_fc fs/namespace.c:3761 [inline] do_new_mount+0x319/0xdc0 fs/namespace.c:3837 do_mount fs/namespace.c:4170 [inline] __do_sys_mount fs/namespace.c:4386 [inline] __se_sys_mount+0x31d/0x420 fs/namespace.c:4363 do_syscall_x64 arch/x86/entry/syscall_64.c:63 [inline] do_syscall_64+0x174/0x580 arch/x86/entry/syscall_64.c:94 entry_SYSCALL_64_after_hwframe+0x77/0x7f Freed by task 23089: 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:253 [inline] __kasan_slab_free+0x5c/0x80 mm/kasan/common.c:285 kasan_slab_free include/linux/kasan.h:235 [inline] slab_free_hook mm/slub.c:2689 [inline] slab_free mm/slub.c:6251 [inline] kfree+0x1c5/0x640 mm/slub.c:6566 lmLogClose+0x296/0x530 fs/jfs/jfs_logmgr.c:-1 jfs_umount+0x2da/0x3b0 fs/jfs/jfs_umount.c:124 jfs_put_super+0x8c/0x190 fs/jfs/super.c:194 generic_shutdown_super+0x13d/0x2d0 fs/super.c:646 kill_block_super+0x44/0x90 fs/super.c:1725 deactivate_locked_super+0xbc/0x130 fs/super.c:476 cleanup_mnt+0x3d3/0x460 fs/namespace.c:1312 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:67 [inline] exit_to_user_mode_loop+0x193/0x6b0 kernel/entry/common.c:98 __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:318 [inline] do_syscall_64+0x353/0x580 arch/x86/entry/syscall_64.c:100 entry_SYSCALL_64_after_hwframe+0x77/0x7f The buggy address belongs to the object at ffff88807f47b800 which belongs to the cache kmalloc-1k of size 1024 The buggy address is located 536 bytes inside of freed 1024-byte region [ffff88807f47b800, ffff88807f47bc00) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x7f478 head: order:3 mapcount:0 entire_mapcount:0 nr_pages_mapped:0 pincount:0 flags: 0xfff00000000040(head|node=0|zone=1|lastcpupid=0x7ff) page_type: f5(slab) raw: 00fff00000000040 ffff88813fe18dc0 dead000000000100 dead000000000122 raw: 0000000000000000 0000000800100010 00000000f5000000 0000000000000000 head: 00fff00000000040 ffff88813fe18dc0 dead000000000100 dead000000000122 head: 0000000000000000 0000000800100010 00000000f5000000 0000000000000000 head: 00fff00000000003 fffffffffffffe01 00000000ffffffff 00000000ffffffff head: ffffffffffffffff 0000000000000000 00000000ffffffff 0000000000000008 page dumped because: kasan: bad access detected page_owner tracks the page as allocated page last allocated via order 3, migratetype Unmovable, gfp_mask 0xd2820(GFP_ATOMIC|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 5628, tgid 5628 (syz-executor), ts 86721145205, free_ts 86710149016 set_page_owner include/linux/page_owner.h:32 [inline] post_alloc_hook+0x22d/0x280 mm/page_alloc.c:1853 prep_new_page mm/page_alloc.c:1861 [inline] get_page_from_freelist+0x24ae/0x2530 mm/page_alloc.c:3941 __alloc_frozen_pages_noprof+0x18d/0x380 mm/page_alloc.c:5221 alloc_slab_page mm/slub.c:3278 [inline] allocate_slab+0x77/0x660 mm/slub.c:3467 new_slab mm/slub.c:3525 [inline] refill_objects+0x336/0x3d0 mm/slub.c:7272 refill_sheaf mm/slub.c:2816 [inline] __pcs_replace_empty_main+0x320/0x720 mm/slub.c:4652 alloc_from_pcs mm/slub.c:4750 [inline] slab_alloc_node mm/slub.c:4884 [inline] __kmalloc_cache_noprof+0x388/0x660 mm/slub.c:5415 kmalloc_noprof include/linux/slab.h:950 [inline] kzalloc_noprof include/linux/slab.h:1188 [inline] batadv_hardif_add_interface net/batman-adv/hard-interface.c:874 [inline] batadv_hard_if_event+0xe64/0x16b0 net/batman-adv/hard-interface.c:958 notifier_call_chain+0x1a5/0x3d0 kernel/notifier.c:85 call_netdevice_notifiers_extack net/core/dev.c:2287 [inline] call_netdevice_notifiers net/core/dev.c:2301 [inline] register_netdevice+0x18db/0x1f00 net/core/dev.c:11461 veth_newlink+0x676/0xb70 drivers/net/veth.c:1890 rtnl_newlink_create+0x310/0xb00 net/core/rtnetlink.c:3864 __rtnl_newlink net/core/rtnetlink.c:3995 [inline] rtnl_newlink+0x167f/0x1bd0 net/core/rtnetlink.c:4110 rtnetlink_rcv_msg+0x802/0xc00 net/core/rtnetlink.c:6997 netlink_rcv_skb+0x226/0x4a0 net/netlink/af_netlink.c:2555 netlink_unicast_kernel net/netlink/af_netlink.c:1318 [inline] netlink_unicast+0x7bb/0x940 net/netlink/af_netlink.c:1344 page last free pid 5639 tgid 5639 stack trace: reset_page_owner include/linux/page_owner.h:25 [inline] __free_pages_prepare mm/page_alloc.c:1397 [inline] __free_frozen_pages+0xc0d/0xd20 mm/page_alloc.c:2938 __slab_free+0x274/0x2c0 mm/slub.c:5613 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:350 kasan_slab_alloc include/linux/kasan.h:253 [inline] slab_post_alloc_hook mm/slub.c:4570 [inline] slab_alloc_node mm/slub.c:4899 [inline] __do_kmalloc_node mm/slub.c:5295 [inline] __kmalloc_noprof+0x312/0x750 mm/slub.c:5308 kmalloc_noprof include/linux/slab.h:954 [inline] kzalloc_noprof include/linux/slab.h:1188 [inline] ethnl_default_notify+0x1ab/0xbf0 net/ethtool/netlink.c:989 ethtool_notify net/ethtool/netlink.c:1094 [inline] ethnl_notify_features net/ethtool/netlink.c:1102 [inline] ethnl_netdev_event+0xe2/0x160 net/ethtool/netlink.c:1117 notifier_call_chain+0x1a5/0x3d0 kernel/notifier.c:85 call_netdevice_notifiers_extack net/core/dev.c:2287 [inline] call_netdevice_notifiers net/core/dev.c:2301 [inline] netdev_features_change net/core/dev.c:1590 [inline] netdev_change_features net/core/dev.c:11103 [inline] netdev_compute_master_upper_features+0x944/0xb30 net/core/dev.c:12870 br_add_if+0xc16/0xea0 net/bridge/br_if.c:683 do_set_master+0x563/0x720 net/core/rtnetlink.c:2986 do_setlink+0xe7b/0x4670 net/core/rtnetlink.c:3188 rtnl_changelink net/core/rtnetlink.c:3800 [inline] __rtnl_newlink net/core/rtnetlink.c:3973 [inline] rtnl_newlink+0x15c2/0x1bd0 net/core/rtnetlink.c:4110 rtnetlink_rcv_msg+0x802/0xc00 net/core/rtnetlink.c:6997 netlink_rcv_skb+0x226/0x4a0 net/netlink/af_netlink.c:2555 Memory state around the buggy address: ffff88807f47b900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88807f47b980: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb >ffff88807f47ba00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff88807f47ba80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff88807f47bb00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ==================================================================