CVE-2021-47491

In the Linux kernel, the following vulnerability has been resolved: mm: khugepaged: skip huge page collapse for special files The read-only THP for filesystems will collapse THP for files opened readonly and mapped with VM_EXEC. The intended usecase is to avoid TLB misses for large text segments. But it doesn't restrict the file types so a THP could be collapsed for a non-regular file, for example, block device, if it is opened readonly and mapped with EXEC permission. This may cause bugs, like [1] and [2]. This is definitely not the intended usecase, so just collapse THP for regular files in order to close the attack surface. [[email protected]: fix vm_file check [3]]

The following products are affected by CVE-2021-47491 vulnerability.

Here, you will find a curated list of external links that provide in-depth information to CVE-2021-47491.

URL	Resource
https://git.kernel.org/stable/c/5fcb6fce74ffa614d964667110cf1a516c48c6d9
https://git.kernel.org/stable/c/6d67b2a73b8e3a079c355bab3c1aef7d85a044b8
https://git.kernel.org/stable/c/a4aeaa06d45e90f9b279f0b09de84bd00006e733
https://lore.kernel.org/linux-cve-announce/2024052241-CVE-2021-47491-437d@gregkh/T
https://nvd.nist.gov/vuln/detail/CVE-2021-47491
https://www.cve.org/CVERecord?id=CVE-2021-47491