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BUG: KASAN: use-after-free in lmLogSync+0x7ec/0x894 fs/jfs/jfs_logmgr.c:1005
Write of size 4 at addr ffff0000c9dc0a20 by task jfsCommit/93

CPU: 1 PID: 93 Comm: jfsCommit Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/03/2025
Call trace:
 dump_backtrace+0x1c8/0x1f4 arch/arm64/kernel/stacktrace.c:158
 show_stack+0x2c/0x3c arch/arm64/kernel/stacktrace.c:165
 __dump_stack+0x30/0x40 lib/dump_stack.c:88
 dump_stack_lvl+0xf8/0x160 lib/dump_stack.c:106
 print_address_description+0x88/0x218 mm/kasan/report.c:316
 print_report+0x50/0x68 mm/kasan/report.c:420
 kasan_report+0xa8/0x100 mm/kasan/report.c:524
 __asan_report_store4_noabort+0x2c/0x38 mm/kasan/report_generic.c:355
 lmLogSync+0x7ec/0x894 fs/jfs/jfs_logmgr.c:1005
 jfs_syncpt+0x70/0x94 fs/jfs/jfs_logmgr.c:1041
 txEnd+0x290/0x4f0 fs/jfs/jfs_txnmgr.c:549
 txLazyCommit fs/jfs/jfs_txnmgr.c:2684 [inline]
 jfs_lazycommit+0x498/0x918 fs/jfs/jfs_txnmgr.c:2732
 kthread+0x250/0x2d8 kernel/kthread.c:376
 ret_from_fork+0x10/0x20 arch/arm64/kernel/entry.S:850

Allocated by task 4586:
 kasan_save_stack mm/kasan/common.c:45 [inline]
 kasan_set_track+0x4c/0x80 mm/kasan/common.c:52
 kasan_save_alloc_info+0x28/0x34 mm/kasan/generic.c:505
 ____kasan_kmalloc mm/kasan/common.c:374 [inline]
 __kasan_kmalloc+0xa0/0xb8 mm/kasan/common.c:383
 kasan_kmalloc include/linux/kasan.h:211 [inline]
 kmalloc_trace+0x7c/0x94 mm/slab_common.c:1031
 kmalloc include/linux/slab.h:563 [inline]
 kzalloc include/linux/slab.h:699 [inline]
 open_inline_log fs/jfs/jfs_logmgr.c:1159 [inline]
 lmLogOpen+0x288/0xd58 fs/jfs/jfs_logmgr.c:1069
 jfs_mount_rw+0xe4/0x50c fs/jfs/jfs_mount.c:253
 jfs_fill_super+0x484/0x948 fs/jfs/super.c:565
 mount_bdev+0x264/0x358 fs/super.c:1443
 jfs_do_mount+0x44/0x58 fs/jfs/super.c:670
 legacy_get_tree+0xd4/0x16c fs/fs_context.c:632
 vfs_get_tree+0x90/0x274 fs/super.c:1573
 do_new_mount+0x228/0x810 fs/namespace.c:3078
 path_mount+0x5b4/0xe78 fs/namespace.c:3408
 do_mount fs/namespace.c:3421 [inline]
 __do_sys_mount fs/namespace.c:3629 [inline]
 __se_sys_mount fs/namespace.c:3606 [inline]
 __arm64_sys_mount+0x49c/0x584 fs/namespace.c:3606
 __invoke_syscall arch/arm64/kernel/syscall.c:38 [inline]
 invoke_syscall+0x98/0x2bc arch/arm64/kernel/syscall.c:52
 el0_svc_common+0x138/0x258 arch/arm64/kernel/syscall.c:140
 do_el0_svc+0x58/0x13c arch/arm64/kernel/syscall.c:204
 el0_svc+0x58/0x138 arch/arm64/kernel/entry-common.c:637
 el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:655
 el0t_64_sync+0x18c/0x190 arch/arm64/kernel/entry.S:585

Freed by task 4326:
 kasan_save_stack mm/kasan/common.c:45 [inline]
 kasan_set_track+0x4c/0x80 mm/kasan/common.c:52
 kasan_save_free_info+0x3c/0x60 mm/kasan/generic.c:516
 ____kasan_slab_free+0x148/0x1b0 mm/kasan/common.c:236
 __kasan_slab_free+0x18/0x28 mm/kasan/common.c:244
 kasan_slab_free include/linux/kasan.h:177 [inline]
 slab_free_hook mm/slub.c:1729 [inline]
 slab_free_freelist_hook+0x16c/0x1ec mm/slub.c:1755
 slab_free mm/slub.c:3687 [inline]
 __kmem_cache_free+0xc0/0x224 mm/slub.c:3700
 kfree+0xd0/0x1ac mm/slab_common.c:988
 lmLogClose+0x250/0x4c8 fs/jfs/jfs_logmgr.c:-1
 jfs_umount+0x244/0x328 fs/jfs/jfs_umount.c:116
 jfs_put_super+0x90/0x188 fs/jfs/super.c:194
 generic_shutdown_super+0x130/0x324 fs/super.c:501
 kill_block_super+0x70/0xdc fs/super.c:1470
 deactivate_locked_super+0xac/0x124 fs/super.c:332
 deactivate_super+0xe8/0x108 fs/super.c:363
 cleanup_mnt+0x37c/0x404 fs/namespace.c:1191
 __cleanup_mnt+0x20/0x30 fs/namespace.c:1198
 task_work_run+0x1ec/0x270 kernel/task_work.c:203
 resume_user_mode_work include/linux/resume_user_mode.h:49 [inline]
 do_notify_resume+0x2038/0x2b28 arch/arm64/kernel/signal.c:1137
 prepare_exit_to_user_mode arch/arm64/kernel/entry-common.c:137 [inline]
 exit_to_user_mode arch/arm64/kernel/entry-common.c:142 [inline]
 el0_svc+0x98/0x138 arch/arm64/kernel/entry-common.c:638
 el0t_64_sync_handler+0x84/0xf0 arch/arm64/kernel/entry-common.c:655
 el0t_64_sync+0x18c/0x190 arch/arm64/kernel/entry.S:585

The buggy address belongs to the object at ffff0000c9dc0800
 which belongs to the cache kmalloc-1k of size 1024
The buggy address is located 544 bytes inside of
 1024-byte region [ffff0000c9dc0800, ffff0000c9dc0c00)

The buggy address belongs to the physical page:
page:0000000004eed598 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x109dc0
head:0000000004eed598 order:3 compound_mapcount:0 compound_pincount:0
flags: 0x5ffc00000010200(slab|head|node=0|zone=2|lastcpupid=0x7ff)
raw: 05ffc00000010200 fffffc0003763800 dead000000000003 ffff0000c0002780
raw: 0000000000000000 0000000000100010 00000001ffffffff 0000000000000000
page dumped because: kasan: bad access detected

Memory state around the buggy address:
 ffff0000c9dc0900: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff0000c9dc0980: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff0000c9dc0a00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                               ^
 ffff0000c9dc0a80: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff0000c9dc0b00: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
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