Linux Kernel up to 5.14.14 ocfs2 lib/string.c buffer overflow

Summaryinfo

A vulnerability marked as critical has been reported in Linux Kernel up to 5.14.14. This impacts an unknown function in the library lib/string.c of the component ocfs2. Performing a manipulation results in buffer overflow. This vulnerability is reported as CVE-2021-47458. The attack is possible to be carried out remotely. No exploit exists. It is suggested to upgrade the affected component.

Detailsinfo

A vulnerability was found in Linux Kernel up to 5.14.14. It has been classified as critical. This affects an unknown code in the library lib/string.c of the component ocfs2. The manipulation with an unknown input leads to a buffer overflow vulnerability. CWE is classifying the issue as CWE-120. The product copies an input buffer to an output buffer without verifying that the size of the input buffer is less than the size of the output buffer, leading to a buffer overflow. This is going to have an impact on confidentiality, integrity, and availability. The summary by CVE is:

In the Linux kernel, the following vulnerability has been resolved: ocfs2: mount fails with buffer overflow in strlen Starting with kernel 5.11 built with CONFIG_FORTIFY_SOURCE mouting an ocfs2 filesystem with either o2cb or pcmk cluster stack fails with the trace below. Problem seems to be that strings for cluster stack and cluster name are not guaranteed to be null terminated in the disk representation, while strlcpy assumes that the source string is always null terminated. This causes a read outside of the source string triggering the buffer overflow detection. detected buffer overflow in strlen ------------[ cut here ]------------ kernel BUG at lib/string.c:1149! invalid opcode: 0000 [#1] SMP PTI CPU: 1 PID: 910 Comm: mount.ocfs2 Not tainted 5.14.0-1-amd64 #1 Debian 5.14.6-2 RIP: 0010:fortify_panic+0xf/0x11 ... Call Trace: ocfs2_initialize_super.isra.0.cold+0xc/0x18 [ocfs2] ocfs2_fill_super+0x359/0x19b0 [ocfs2] mount_bdev+0x185/0x1b0 legacy_get_tree+0x27/0x40 vfs_get_tree+0x25/0xb0 path_mount+0x454/0xa20 __x64_sys_mount+0x103/0x140 do_syscall_64+0x3b/0xc0 entry_SYSCALL_64_after_hwframe+0x44/0xae

The advisory is shared at git.kernel.org. This vulnerability is uniquely identified as CVE-2021-47458 since 05/21/2024. The exploitability is told to be easy. It is possible to initiate the attack remotely. Technical details are known, but no exploit is available. The price for an exploit might be around USD $0-$5k at the moment (estimation calculated on 09/24/2025).

The vulnerability scanner Nessus provides a plugin with the ID 239865 (TencentOS Server 3: kernel (TSSA-2024:1035)), which helps to determine the existence of the flaw in a target environment.

Upgrading to version 4.4.290, 4.9.288, 4.14.253, 4.19.214, 5.4.156, 5.10.76 or 5.14.15 eliminates this vulnerability. Applying the patch ac011cb3ff7a/4b74ddcc22ee/232ed9752510/7623b1035ca2/d3a83576378b/93be0eeea14c/0e677ea5b739/b15fa9224e6e is able to eliminate this problem. The bugfix is ready for download at git.kernel.org. The best possible mitigation is suggested to be upgrading to the latest version.

The vulnerability is also documented in the vulnerability database at Tenable (239865). Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

Productinfo

Type

• Operating System

Vendor

• Linux

Name

• Kernel

Version

• 4.4.289
• 4.9.287
• 4.14.252
• 4.19.213
• 5.4.155
• 5.10.0
• 5.10.1
• 5.10.2
• 5.10.3
• 5.10.4
• 5.10.5
• 5.10.6
• 5.10.7
• 5.10.8
• 5.10.9
• 5.10.10
• 5.10.11
• 5.10.12
• 5.10.13
• 5.10.14
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• 5.10.16
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• 5.10.19
• 5.10.20
• 5.10.21
• 5.10.22
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• 5.10.28
• 5.10.29
• 5.10.30
• 5.10.31
• 5.10.32
• 5.10.33
• 5.10.34
• 5.10.35
• 5.10.36
• 5.10.37
• 5.10.38
• 5.10.39
• 5.10.40
• 5.10.41
• 5.10.42
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• 5.10.46
• 5.10.47
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• 5.10.50
• 5.10.51
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• 5.10.53
• 5.10.54
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• 5.10.56
• 5.10.57
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• 5.10.61
• 5.10.62
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• 5.10.64
• 5.10.65
• 5.10.66
• 5.10.67
• 5.10.68
• 5.10.69
• 5.10.70
• 5.10.71
• 5.10.72
• 5.10.73
• 5.10.74
• 5.10.75
• 5.14.0
• 5.14.1
• 5.14.2
• 5.14.3
• 5.14.4
• 5.14.5
• 5.14.6
• 5.14.7
• 5.14.8
• 5.14.9
• 5.14.10
• 5.14.11
• 5.14.12
• 5.14.13
• 5.14.14

License

• open-source

Website

• Vendor: https://www.kernel.org/

CPE 2.3info

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CPE 2.2info

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Entryinfo

Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

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