Memory Consumption Issue in Linux Kernel with ext4 Filesystem

CVE-2025-40179

What is CVE-2025-40179?

A vulnerability in the Linux kernel's ext4 filesystem allows for the creation of orphan files that can be excessively large, leading to significant memory consumption. As orphan files are processed, the kernel traverses large file sizes while pinning buffers in memory, potentially exhausting system resources. The vulnerability has been addressed by imposing a limit on the ostensible size of orphan files and employing kvmalloc() for the allocation of block descriptor structures, which mitigates the risk associated with large order memory allocations while maintaining performance for reasonably sized orphan files.

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