... Log Wrap ... Log Wrap ... Log Wrap ...
==================================================================
BUG: KASAN: use-after-free in lmLogSync+0x94e/0x9e0 fs/jfs/jfs_logmgr.c:1005
Write of size 4 at addr ffff888055b82220 by task jfsCommit/108

CPU: 1 PID: 108 Comm: jfsCommit Not tainted syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 05/09/2026
Call Trace:
 <TASK>
 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
 lmLogSync+0x94e/0x9e0 fs/jfs/jfs_logmgr.c:1005
 jfs_syncpt+0x77/0x90 fs/jfs/jfs_logmgr.c:1041
 txEnd+0x2e1/0x520 fs/jfs/jfs_txnmgr.c:550
 txLazyCommit fs/jfs/jfs_txnmgr.c:2685 [inline]
 jfs_lazycommit+0x5a0/0xa70 fs/jfs/jfs_txnmgr.c:2733
 kthread+0x29d/0x330 kernel/kthread.c:376
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
 </TASK>

Allocated by task 4986:
 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]
 open_inline_log fs/jfs/jfs_logmgr.c:1159 [inline]
 lmLogOpen+0x2c0/0xf90 fs/jfs/jfs_logmgr.c:1069
 jfs_mount_rw+0xf8/0x5c0 fs/jfs/jfs_mount.c:253
 jfs_fill_super+0x594/0xad0 fs/jfs/super.c:565
 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 4272:
 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
 lmLogClose+0x293/0x520 fs/jfs/jfs_logmgr.c:-1
 jfs_umount+0x28f/0x360 fs/jfs/jfs_umount.c:116
 jfs_put_super+0x88/0x190 fs/jfs/super.c:194
 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

The buggy address belongs to the object at ffff888055b82000
 which belongs to the cache kmalloc-1k of size 1024
The buggy address is located 544 bytes inside of
 1024-byte region [ffff888055b82000, ffff888055b82400)

The buggy address belongs to the physical page:
page:ffffea000156e000 refcount:1 mapcount:0 mapping:0000000000000000 index:0x0 pfn:0x55b80
head:ffffea000156e000 order:3 compound_mapcount:0 compound_pincount:0
flags: 0xfff00000010200(slab|head|node=0|zone=1|lastcpupid=0x7ff)
raw: 00fff00000010200 ffffea0001e40400 dead000000000002 ffff888017441dc0
raw: 0000000000000000 0000000000100010 00000001ffffffff 0000000000000000
page dumped because: kasan: bad access detected
page_owner tracks the page as allocated
page last allocated via order 3, migratetype Unmovable, gfp_mask 0xd20c0(__GFP_IO|__GFP_FS|__GFP_NOWARN|__GFP_NORETRY|__GFP_COMP|__GFP_NOMEMALLOC), pid 4354, tgid 4354 (kworker/u4:0), ts 83927964688, free_ts 26891529483
 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]
 load_elf_phdrs fs/binfmt_elf.c:507 [inline]
 load_elf_binary+0x264/0x2800 fs/binfmt_elf.c:887
 search_binary_handler fs/exec.c:1764 [inline]
 exec_binprm fs/exec.c:1805 [inline]
 bprm_execve+0xaea/0x17e0 fs/exec.c:1874
 kernel_execve+0x8b9/0x9c0 fs/exec.c:2039
 call_usermodehelper_exec_async+0x207/0x350 kernel/umh.c:113
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295
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
 free_contig_range+0x9d/0x150 mm/page_alloc.c:9625
 destroy_args+0xf0/0xa0a mm/debug_vm_pgtable.c:1031
 debug_vm_pgtable+0x33c/0x38e mm/debug_vm_pgtable.c:1359
 do_one_initcall+0x26a/0x840 init/main.c:1309
 do_initcall_level+0x137/0x1e4 init/main.c:1382
 do_initcalls+0x4b/0x8a init/main.c:1398
 kernel_init_freeable+0x415/0x5be init/main.c:1637
 kernel_init+0x19/0x1b0 init/main.c:1525
 ret_from_fork+0x1f/0x30 arch/x86/entry/entry_64.S:295

Memory state around the buggy address:
 ffff888055b82100: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff888055b82180: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
>ffff888055b82200: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
                               ^
 ffff888055b82280: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
 ffff888055b82300: fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb fb
==================================================================