Inode Reference Leak in Linux Kernel's Ext4 Filesystem

CVE-2026-43066

What is CVE-2026-43066?

A vulnerability exists in the Linux kernel's Ext4 filesystem where an inode reference can be leaked during error handling in the ext4_fc_replay_inode() function. When certain operations fail, such as ext4_handle_dirty_metadata() or sync_dirty_buffer(), the function may skip the necessary release of the inode's buffer head, iloc.bh. This oversight can lead to memory leaks and potential resource exhaustion. A remedial fix introduces a new error handling path to ensure that iloc.bh is always properly released, thereby improving the stability and security of the filesystem.

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