CVE-2023-53616 jfs: fix invalid free of JFS_IP(ipimap)->i_imap in diUnmount
A double-free vulnerability in the Linux kernel's JFS filesystem allows local attackers to cause a system crash or potentially execute arbitrary code.
- Exploited in the wild
- Not known
- Login needed
- Any signed-in user
- Attackable
- Local or same network only
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2023-53616?
CVE-2023-53616 is a high-severity use after free vulnerability in Linux kernel, published on 4 Oct 2025. It can only be exploited from the same machine or local network, with no action from the victim.
Official description
In the Linux kernel, the following vulnerability has been resolved:
jfs: fix invalid free of JFS_IP(ipimap)->i_imap in diUnmount
syzbot found an invalid-free in diUnmount:
BUG: KASAN: double-free in slab_free mm/slub.c:3661 [inline] BUG: KASAN: double-free in __kmem_cache_free+0x71/0x110 mm/slub.c:3674 Free of addr ffff88806f410000 by task syz-executor131/3632
CPU: 0 PID: 3632 Comm: syz-executor131 Not tainted 6.1.0-rc7-syzkaller-00012-gca57f02295f1 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/26/2022 Call Trace: <TASK> __dump_stack lib/dump_stack.c:88 [inline] dump_stack_lvl+0x1b1/0x28e lib/dump_stack.c:106 print_address_description+0x74/0x340 mm/kasan/report.c:284 print_report+0x107/0x1f0 mm/kasan/report.c:395 kasan_report_invalid_free+0xac/0xd0 mm/kasan/report.c:460 ____kasan_slab_free+0xfb/0x120 kasan_slab_free include/linux/kasan.h:177 [inline] slab_free_hook mm/slub.c:1724 [inline] slab_free_freelist_hook+0x12e/0x1a0 mm/slub.c:1750 slab_free mm/slub.c:3661 [inline] __kmem_cache_free+0x71/0x110 mm/slub.c:3674 diUnmount+0xef/0x100 fs/jfs/jfs_imap.c:195 jfs_umount+0x108/0x370 fs/jfs/jfs_umount.c:63 jfs_put_super+0x86/0x190 fs/jfs/super.c:194 generic_shutdown_super+0x130/0x310 fs/super.c:492 kill_block_super+0x79/0xd0 fs/super.c:1428 deactivate_locked_super+0xa7/0xf0 fs/super.c:332 cleanup_mnt+0x494/0x520 fs/namespace.c:1186 task_work_run+0x243/0x300 kernel/task_work.c:179 exit_task_work include/linux/task_work.h:38 [inline] do_exit+0x664/0x2070 kernel/exit.c:820 do_group_exit+0x1fd/0x2b0 kernel/exit.c:950 __do_sys_exit_group kernel/exit.c:961 [inline] __se_sys_exit_group kernel/exit.c:959 [inline] __x64_sys_exit_group+0x3b/0x40 kernel/exit.c:959 do_syscall_x64 arch/x86/entry/common.c:50 [inline] do_syscall_64+0x3d/0xb0 arch/x86/entry/common.c:80 entry_SYSCALL_64_after_hwframe+0x63/0xcd [...]
JFS_IP(ipimap)->i_imap is not setting to NULL after free in diUnmount. If jfs_remount() free JFS_IP(ipimap)->i_imap but then failed at diMount(). JFS_IP(ipimap)->i_imap will be freed once again. Fix this problem by setting JFS_IP(ipimap)->i_imap to NULL after free.
Weakness: CWE-415
Which versions are affected by CVE-2023-53616?
It affects 1 product.
Products include Linux kernel.
How do I fix CVE-2023-53616?
Apply the vendor's patch.
Upgrade to the fixed version. These bugs are found with fuzzing and sanitisers and avoided by memory-safe languages. More about Use after free.
Is CVE-2023-53616 being exploited?
There is no known exploitation of CVE-2023-53616 in the wild and no public exploit code.
Other vulnerabilities in Linux kernel
Sources
Also known as BELL-CVE-2023-53616, DEBIAN-CVE-2023-53616, GHSA-v852-w8jm-hg43, UBUNTU-CVE-2023-53616.