# CVE-2023-52604: FS:JFS:UBSAN:array-index-out-of-bounds in dbAdjTree
> An out-of-bounds array index in the JFS filesystem can cause a kernel panic, leading to denial of service.
- **Severity:** High 7.8 (`CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H`)
- **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:** Yes
- **Published:** 6 Mar 2024
- **Updated:** 5 Aug 2026
- **Also known as:** BELL-CVE-2023-52604, DEBIAN-CVE-2023-52604, GHSA-4rwf-mvg8-5p8w, UBUNTU-CVE-2023-52604
## What is CVE-2023-52604?
CVE-2023-52604 is a high-severity memory corruption vulnerability in Linux kernel, published on 6 Mar 2024. 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:
FS:JFS:UBSAN:array-index-out-of-bounds in dbAdjTree
Syzkaller reported the following issue:
UBSAN: array-index-out-of-bounds in fs/jfs/jfs_dmap.c:2867:6
index 196694 is out of range for type 's8[1365]' (aka 'signed char[1365]')
CPU: 1 PID: 109 Comm: jfsCommit Not tainted 6.6.0-rc3-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/04/2023
Call Trace:
__dump_stack lib/dump_stack.c:88 [inline]
dump_stack_lvl+0x1e7/0x2d0 lib/dump_stack.c:106
ubsan_epilogue lib/ubsan.c:217 [inline]
__ubsan_handle_out_of_bounds+0x11c/0x150 lib/ubsan.c:348
dbAdjTree+0x474/0x4f0 fs/jfs/jfs_dmap.c:2867
dbJoin+0x210/0x2d0 fs/jfs/jfs_dmap.c:2834
dbFreeBits+0x4eb/0xda0 fs/jfs/jfs_dmap.c:2331
dbFreeDmap fs/jfs/jfs_dmap.c:2080 [inline]
dbFree+0x343/0x650 fs/jfs/jfs_dmap.c:402
txFreeMap+0x798/0xd50 fs/jfs/jfs_txnmgr.c:2534
txUpdateMap+0x342/0x9e0
txLazyCommit fs/jfs/jfs_txnmgr.c:2664 [inline]
jfs_lazycommit+0x47a/0xb70 fs/jfs/jfs_txnmgr.c:2732
kthread+0x2d3/0x370 kernel/kthread.c:388
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:304
================================================================================
Kernel panic - not syncing: UBSAN: panic_on_warn set ...
CPU: 1 PID: 109 Comm: jfsCommit Not tainted 6.6.0-rc3-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 08/04/2023
Call Trace:
__dump_stack lib/dump_stack.c:88 [inline]
dump_stack_lvl+0x1e7/0x2d0 lib/dump_stack.c:106
panic+0x30f/0x770 kernel/panic.c:340
check_panic_on_warn+0x82/0xa0 kernel/panic.c:236
ubsan_epilogue lib/ubsan.c:223 [inline]
__ubsan_handle_out_of_bounds+0x13c/0x150 lib/ubsan.c:348
dbAdjTree+0x474/0x4f0 fs/jfs/jfs_dmap.c:2867
dbJoin+0x210/0x2d0 fs/jfs/jfs_dmap.c:2834
dbFreeBits+0x4eb/0xda0 fs/jfs/jfs_dmap.c:2331
dbFreeDmap fs/jfs/jfs_dmap.c:2080 [inline]
dbFree+0x343/0x650 fs/jfs/jfs_dmap.c:402
txFreeMap+0x798/0xd50 fs/jfs/jfs_txnmgr.c:2534
txUpdateMap+0x342/0x9e0
txLazyCommit fs/jfs/jfs_txnmgr.c:2664 [inline]
jfs_lazycommit+0x47a/0xb70 fs/jfs/jfs_txnmgr.c:2732
kthread+0x2d3/0x370 kernel/kthread.c:388
ret_from_fork+0x48/0x80 arch/x86/kernel/process.c:147
ret_from_fork_asm+0x11/0x20 arch/x86/entry/entry_64.S:304
Kernel Offset: disabled
Rebooting in 86400 seconds..
The issue is caused when the value of lp becomes greater than
CTLTREESIZE which is the max size of stree. Adding a simple check
solves this issue.
Dave:
As the function returns a void, good error handling
would require a more intrusive code reorganization, so I modified
Osama's patch at use WARN_ON_ONCE for lack of a cleaner option.
The patch is tested via syzbot.
Weakness: CWE-129 (Improper Validation of Array Index)
## Which versions are affected by CVE-2023-52604?
It affects 1 product.
Products: Linux kernel.
## How do I fix CVE-2023-52604?
Apply the vendor's patch.
## Is CVE-2023-52604 being exploited?
There is no known exploitation of CVE-2023-52604 in the wild and no public exploit code.
## Other vulnerabilities in Linux kernel
- [CVE-2026-53266](https://insights.sbomify.com/CVE-2026-53266/): Linux Kernel Out-of-Bounds Write (high 8.8, exploited in the wild)
- [CVE-2013-6282](https://insights.sbomify.com/CVE-2013-6282/): Linux Kernel Improper Input Validation (high 8.8, exploited in the wild)
- [CVE-2022-0185](https://insights.sbomify.com/CVE-2022-0185/): Linux Kernel Heap-Based Buffer Overflow (high 8.4, exploited in the wild)
- [CVE-2013-2094](https://insights.sbomify.com/CVE-2013-2094/): Linux Kernel Privilege Escalation (high 8.4, exploited in the wild)
- [CVE-2026-53362](https://insights.sbomify.com/CVE-2026-53362/): Linux Kernel Unspecified (high 7.8, exploited in the wild)
## Fix prompt for AI coding agents
```text
Check this codebase for CVE-2023-52604 and fix it if it is affected.
What it is: CVE-2023-52604 is a high-severity memory corruption vulnerability in Linux kernel, published on 6 Mar 2024. It can only be exploited from the same machine or local network, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2023-52604 in the wild and no public exploit code.
Affected product: Linux kernel. No package-level version data is available, so check the vendor advisory linked from the reference page.
Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.
Reference: https://insights.sbomify.com/CVE-2023-52604/ (Markdown: https://insights.sbomify.com/CVE-2023-52604/index.md)
```
## Sources
- CVE record: https://www.cve.org/CVERecord?id=CVE-2023-52604
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2023-52604
- OSV: https://osv.dev/vulnerability/CVE-2023-52604
---
From sbomify Insights: https://insights.sbomify.com/CVE-2023-52604/
Summaries are generated and may contain mistakes; the official description above is the record.