================================================================== BUG: KASAN: slab-use-after-free in lbmIODone+0x130e/0x16b0 fs/jfs/jfs_logmgr.c:2192 Read of size 4 at addr ffff8880600b7408 by task syz-executor/6963 CPU: 0 UID: 0 PID: 6963 Comm: syz-executor Not tainted syzkaller #0 PREEMPT_{RT,(full)} Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 07/24/2026 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 lbmIODone+0x130e/0x16b0 fs/jfs/jfs_logmgr.c:2192 blk_update_request+0x57b/0xe50 block/blk-mq.c:1016 blk_mq_end_request+0x3e/0x70 block/blk-mq.c:1147 blk_complete_reqs block/blk-mq.c:1222 [inline] blk_done_softirq+0x10a/0x160 block/blk-mq.c:1227 handle_softirqs+0x1da/0x6d0 kernel/softirq.c:645 __do_softirq kernel/softirq.c:679 [inline] __local_bh_enable_ip+0x16f/0x2b0 kernel/softirq.c:325 local_bh_enable include/linux/bottom_half.h:33 [inline] __alloc_skb+0x1b1/0x7a0 net/core/skbuff.c:699 alloc_skb include/linux/skbuff.h:1384 [inline] bt_skb_alloc include/net/bluetooth/bluetooth.h:517 [inline] vhci_get_user drivers/bluetooth/hci_vhci.c:506 [inline] vhci_write+0xc2/0x480 drivers/bluetooth/hci_vhci.c:626 do_iter_readv_writev+0x624/0x8d0 fs/read_write.c:-1 vfs_writev+0x34c/0x990 fs/read_write.c:1058 do_writev+0x15a/0x2e0 fs/read_write.c:1104 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 RIP: 0033:0x7fd5dd64e90e Code: 08 0f 85 a5 a8 ff ff 49 89 fb 48 89 f0 48 89 d7 48 89 ce 4c 89 c2 4d 89 ca 4c 8b 44 24 08 4c 8b 4c 24 10 4c 89 5c 24 08 0f 05 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 80 00 00 00 00 48 83 ec 08 RSP: 002b:00007fd5dc0e6b38 EFLAGS: 00000246 ORIG_RAX: 0000000000000014 RAX: ffffffffffffffda RBX: 00007fd5dc0e76c0 RCX: 00007fd5dd64e90e RDX: 0000000000000004 RSI: 00007fd5dc0e6bb0 RDI: 00000000000000ca RBP: 00007fd5dc0e6d00 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 000600046003fd00 R13: 000000000000001c R14: 00007ffe37b16330 R15: 00007ffe37b16418 Allocated by task 6924: 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+0x3d5/0x680 mm/slub.c:5563 _kmalloc_noprof include/linux/slab.h:991 [inline] lbmLogInit fs/jfs/jfs_logmgr.c:1819 [inline] lmLogInit+0x3e5/0x1a20 fs/jfs/jfs_logmgr.c:1267 open_inline_log fs/jfs/jfs_logmgr.c:1173 [inline] lmLogOpen+0x4e3/0xf90 fs/jfs/jfs_logmgr.c:1067 jfs_mount_rw+0xf3/0x670 fs/jfs/jfs_mount.c:257 jfs_fill_super+0x769/0xda0 fs/jfs/super.c:533 get_tree_bdev_flags+0x430/0x4f0 fs/super.c:1887 vfs_get_tree+0x92/0x2a0 fs/super.c:1947 fc_mount fs/namespace.c:1198 [inline] do_new_mount_fc fs/namespace.c:3772 [inline] do_new_mount+0x319/0xdc0 fs/namespace.c:3848 do_mount fs/namespace.c:4181 [inline] __do_sys_mount fs/namespace.c:4397 [inline] __se_sys_mount+0x31d/0x420 fs/namespace.c:4374 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 5583: 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:2748 [inline] slab_free mm/slub.c:6499 [inline] kfree+0x1c5/0x6d0 mm/slub.c:6792 lbmLogShutdown fs/jfs/jfs_logmgr.c:1862 [inline] lmLogShutdown+0x456/0x850 fs/jfs/jfs_logmgr.c:1681 lmLogClose+0x28c/0x530 fs/jfs/jfs_logmgr.c:1457 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:769 kill_block_super+0x44/0xa0 fs/super.c:1918 deactivate_locked_super+0xbc/0x110 fs/super.c:603 cleanup_mnt+0x3d3/0x460 fs/namespace.c:1317 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:336 [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 ffff8880600b7400 which belongs to the cache kmalloc-256 of size 256 The buggy address is located 8 bytes inside of freed 256-byte region [ffff8880600b7400, ffff8880600b7500) The buggy address belongs to the physical page: page: refcount:0 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x600b6 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 ffff88813ffbab40 dead000000000100 dead000000000122 raw: 0000000000000000 0000000000100010 00000000f5000000 0000000000000000 head: 0080000000000040 ffff88813ffbab40 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 5582, tgid 5582 (syz-executor), ts 91734164467 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:7410 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:3915 devinet_sysctl_register+0xad/0x200 net/ipv4/devinet.c:2781 inetdev_init+0x29e/0x4d0 net/ipv4/devinet.c:291 inetdev_event+0x307/0x15e0 net/ipv4/devinet.c:1590 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:11541 macvlan_common_newlink+0x12f3/0x1a60 drivers/net/macvlan.c:1575 macvtap_newlink+0x13c/0x1b0 drivers/net/macvtap.c:109 page_owner free stack trace missing Memory state around the buggy address: ffff8880600b7300: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc ffff8880600b7380: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc >ffff8880600b7400: fa fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ^ ffff8880600b7480: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb ffff8880600b7500: fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc fc 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