CVE-2026-23423

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 thats 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.

Weakness

The product does not sufficiently track and release allocated memory after it has been used, making the memory unavailable for reallocation and reuse.

Affected Software

Potential Mitigations

• Choose a language or tool that provides automatic memory management, or makes manual memory management less error-prone.
• For example, glibc in Linux provides protection against free of invalid pointers.
• When using Xcode to target OS X or iOS, enable automatic reference counting (ARC) [REF-391].
• To help correctly and consistently manage memory when programming in C++, consider using a smart pointer class such as std::auto_ptr (defined by ISO/IEC ISO/IEC 14882:2003), std::shared_ptr and std::unique_ptr (specified by an upcoming revision of the C++ standard, informally referred to as C++ 1x), or equivalent solutions such as Boost.

References

• https://git.kernel.org/stable/c/3f501412f2079ca14bf68a18d80a2b7a823f1f64
• https://git.kernel.org/stable/c/628895890b0c9ac9129129e89455da7db95ba343
• https://git.kernel.org/stable/c/d4f210de01eaccac61eee657f676045ef9771d07