CVE-2021-47179

MEDIUM
Published Mar 25, 2024 Modified Nov 21, 2024 CWE-476

Description

In the Linux kernel, the following vulnerability has been resolved: NFSv4: Fix a NULL pointer dereference in pnfs_mark_matching_lsegs_return() Commit de144ff4234f changes _pnfs_return_layout() to call pnfs_mark_matching_lsegs_return() passing NULL as the struct pnfs_layout_range argument. Unfortunately, pnfs_mark_matching_lsegs_return() doesn't check if we have a value here before dereferencing it, causing an oops. I'm able to hit this crash consistently when running connectathon basic tests on NFS v4.1/v4.2 against Ontap.

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CVSS v3.1 Score

5.5
MEDIUM
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

Weakness Type (CWE)

CWE-476 CWE-476

Affected Products

Vendor Product
linux linux_kernel
linux linux_kernel
linux linux_kernel
linux linux_kernel
linux linux_kernel
linux linux_kernel

References

Advisories & Patches

https://git.kernel.org/stable/c/39785761feadf261bc5101372b0b0bbaf6a94494 https://git.kernel.org/stable/c/42637ca25c7d7b5a92804a679af5192e8c1a9f48 https://git.kernel.org/stable/c/4e1ba532dbc1a0e19fc2458d74ab8d98680c4e42 https://git.kernel.org/stable/c/a421d218603ffa822a0b8045055c03eae394a7eb https://git.kernel.org/stable/c/aba3c7795f51717ae316f3566442dee7cc3eeccb https://git.kernel.org/stable/c/b090d110e66636bca473fd8b98d5c97b555a965a https://git.kernel.org/stable/c/f9890652185b72b8de9ebeb4406037640b6e1b53 https://git.kernel.org/stable/c/39785761feadf261bc5101372b0b0bbaf6a94494 https://git.kernel.org/stable/c/42637ca25c7d7b5a92804a679af5192e8c1a9f48 https://git.kernel.org/stable/c/4e1ba532dbc1a0e19fc2458d74ab8d98680c4e42 https://git.kernel.org/stable/c/a421d218603ffa822a0b8045055c03eae394a7eb https://git.kernel.org/stable/c/aba3c7795f51717ae316f3566442dee7cc3eeccb https://git.kernel.org/stable/c/b090d110e66636bca473fd8b98d5c97b555a965a https://git.kernel.org/stable/c/f9890652185b72b8de9ebeb4406037640b6e1b53

Frequently Asked Questions

What is CVE-2021-47179? +
In the Linux kernel, the following vulnerability has been resolved: NFSv4: Fix a NULL pointer dereference in pnfs_mark_matching_lsegs_return() Commit de144ff4234f changes _pnfs_return_layout() to call pnfs_mark_matching_lsegs_return() passing NULL as the struct pnfs_layout_range argument. Unfortunately, pnfs_mark_matching_lsegs_return() doesn't check if we have a value here before dereferencing it, causing an oops. I'm able to hit this crash consistently when running connectathon basic tests on NFS v4.1/v4.2 against Ontap. It has a CVSS v3.1 base score of 5.5 (MEDIUM).
How severe is CVE-2021-47179? +
CVE-2021-47179 has a CVSS v3.1 score of 5.5 out of 10, rated MEDIUM. This is a medium-severity vulnerability that should be remediated as part of regular maintenance.
What products are affected by CVE-2021-47179? +
CVE-2021-47179 affects products from linux, specifically: linux_kernel. Check the affected products table above for specific version ranges.
How do I check if I'm vulnerable to CVE-2021-47179? +
You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

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