# CVE-2024-57923: btrfs: zlib: fix avail_in bytes for s390 zlib HW compression path > A flaw in the Linux kernel's btrfs zlib compression on s390 hardware can cause a kernel panic, leading to denial of service. - **Severity:** Medium 5.5 (`CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/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:** 19 Jan 2025 - **Updated:** 11 May 2026 - **Also known as:** BELL-CVE-2024-57923, DEBIAN-CVE-2024-57923, GHSA-vxxv-c26q-48f2, UBUNTU-CVE-2024-57923 ## What is CVE-2024-57923? CVE-2024-57923 is a medium-severity denial of service vulnerability in Linux kernel, published on 19 Jan 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: btrfs: zlib: fix avail_in bytes for s390 zlib HW compression path Since the input data length passed to zlib_compress_folios() can be arbitrary, always setting strm.avail_in to a multiple of PAGE_SIZE may cause read-in bytes to exceed the input range. Currently this triggers an assert in btrfs_compress_folios() on the debug kernel (see below). Fix strm.avail_in calculation for S390 hardware acceleration path. assertion failed: *total_in <= orig_len, in fs/btrfs/compression.c:1041 ------------[ cut here ]------------ kernel BUG at fs/btrfs/compression.c:1041! monitor event: 0040 ilc:2 [#1] PREEMPT SMP CPU: 16 UID: 0 PID: 325 Comm: kworker/u273:3 Not tainted 6.13.0-20241204.rc1.git6.fae3b21430ca.300.fc41.s390x+debug #1 Hardware name: IBM 3931 A01 703 (z/VM 7.4.0) Workqueue: btrfs-delalloc btrfs_work_helper Krnl PSW : 0704d00180000000 0000021761df6538 (btrfs_compress_folios+0x198/0x1a0) R:0 T:1 IO:1 EX:1 Key:0 M:1 W:0 P:0 AS:3 CC:1 PM:0 RI:0 EA:3 Krnl GPRS: 0000000080000000 0000000000000001 0000000000000047 0000000000000000 0000000000000006 ffffff01757bb000 000001976232fcc0 000000000000130c 000001976232fcd0 000001976232fcc8 00000118ff4a0e30 0000000000000001 00000111821ab400 0000011100000000 0000021761df6534 000001976232fb58 Krnl Code: 0000021761df6528: c020006f5ef4 larl %r2,0000021762be2310 0000021761df652e: c0e5ffbd09d5 brasl %r14,00000217615978d8 #0000021761df6534: af000000 mc 0,0 >0000021761df6538: 0707 bcr 0,%r7 0000021761df653a: 0707 bcr 0,%r7 0000021761df653c: 0707 bcr 0,%r7 0000021761df653e: 0707 bcr 0,%r7 0000021761df6540: c004004bb7ec brcl 0,000002176276d518 Call Trace: [<0000021761df6538>] btrfs_compress_folios+0x198/0x1a0 ([<0000021761df6534>] btrfs_compress_folios+0x194/0x1a0) [<0000021761d97788>] compress_file_range+0x3b8/0x6d0 [<0000021761dcee7c>] btrfs_work_helper+0x10c/0x160 [<0000021761645760>] process_one_work+0x2b0/0x5d0 [<000002176164637e>] worker_thread+0x20e/0x3e0 [<000002176165221a>] kthread+0x15a/0x170 [<00000217615b859c>] __ret_from_fork+0x3c/0x60 [<00000217626e72d2>] ret_from_fork+0xa/0x38 INFO: lockdep is turned off. Last Breaking-Event-Address: [<0000021761597924>] _printk+0x4c/0x58 Kernel panic - not syncing: Fatal exception: panic_on_oops Weakness: CWE-617 (Reachable Assertion) ## Which versions are affected by CVE-2024-57923? It affects 1 product. Products: Linux kernel. ## How do I fix CVE-2024-57923? Apply the vendor's patch. ## Is CVE-2024-57923 being exploited? There is no known exploitation of CVE-2024-57923 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-2024-57923 and fix it if it is affected. What it is: CVE-2024-57923 is a medium-severity denial of service vulnerability in Linux kernel, published on 19 Jan 2025. 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-2024-57923 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-2024-57923/ (Markdown: https://insights.sbomify.com/CVE-2024-57923/index.md) ``` ## Sources - CVE record: https://www.cve.org/CVERecord?id=CVE-2024-57923 - NVD: https://nvd.nist.gov/vuln/detail/CVE-2024-57923 - OSV: https://osv.dev/vulnerability/CVE-2024-57923 --- From sbomify Insights: https://insights.sbomify.com/CVE-2024-57923/ Summaries are generated and may contain mistakes; the official description above is the record.