CVE-2023-53813

A flaw was identified in the ext4 filesystem’s block preallocation allocator in the Linux kernel. During allocation, the code traverses an rbtree of per-inode preallocations.Concurrently, the helper ext4_mb_discard_group_preallocation() can mark PAs as deleted, which may cause a naive rbtree traversal to skip eligible entries. In certain conditions, this inconsistent traversal can result in missing a preallocation that would satisfy the allocation request and instead creating a new preallocation that overlaps an existing one. This can lead to the kernel hitting a BUG_ON() or other integrity faults, potentially causing memory corruption or a system crash.

The CVSS score(s) listed for this vulnerability do not reflect the associated product's status, and are included for informational purposes to better understand the severity of this vulnerability.

Mitigation for this issue is either not available or the currently available options don't meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base or stability.