CVE-2026-23423: btrfs: free pages on error in btrfs_uring_read_extent()

Severity: medium (CVSS 5.5 v3.1)
Exploited in the wild: not listed in CISA KEV
EPSS: 0.1% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2026-04-03 · updated 2026-07-24
Weakness: CWE-401

Description

In the Linux kernel, the following vulnerability has been resolved: btrfs: free pages on error in btrfs_uring_read_extent() In this function the 'pages' object is never freed in the hopes that it is picked up by btrfs_uring_read_finished() whenever that executes in the future. But that's just the happy path. Along the way previous allocations might have gone wrong, or we might not get -EIOCBQUEUED from btrfs_encoded_read_regular_fill_pages(). In all these cases, we go to a cleanup section that frees all memory allocated by this function without assuming any deferred execution, and this also needs to happen for the 'pages' allocation.

Affected products

Linux kernel: from 6.13.1 before 6.18.17; from 6.19 before 6.19.7; 6.13, 7.0-rc1, 7.0-rc2, 7.0-rc3, 7.0-rc4, 7.0-rc5 (+2) — fixed in 6.18.17, 6.19.7

How to fix

Upgrade to a fixed version: Linux kernel 6.18.17, 6.19.7. Check the vendor advisory for mitigations.

References

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