Symbolic Link Handling Vulnerability in Btrfs Product from Linux Vendor

CVE-2025-40128

What is CVE-2025-40128?

A vulnerability exists in the Btrfs file system within the Linux kernel, particularly affecting the handling of symbolic links when the block size exceeds the page size. When creating a symbolic link in such scenarios, users may encounter a kernel crash, leading to system instability. This issue arises due to improper handling of inode mapping orders, causing the system to fail during link resolution. A fix has been implemented to ensure that the inode mapping order is correctly set, thereby preventing this crash in affected environments.

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