CVE-2024-42304
In the Linux kernel, the following vulnerability has been resolved: ext4: make sure the first directory block is not a hole The syzbot constructs a directory that has no dirblock but is non-inline, i.e. the first directory block is a hole.
Does this matter?
Lower severity and a low EPSS score (0.23%). Track it; it rarely justifies an emergency change on its own.
Description
In the Linux kernel, the following vulnerability has been resolved: ext4: make sure the first directory block is not a hole The syzbot constructs a directory that has no dirblock but is non-inline, i.e. the first directory block is a hole. And no errors are reported when creating files in this directory in the following flow. ext4_mknod ... ext4_add_entry // Read block 0 ext4_read_dirblock(dir, block, DIRENT) bh = ext4_bread(NULL, inode, block, 0) if (!bh && (type == INDEX || type == DIRENT_HTREE)) // The first directory block is a hole // But type == DIRENT, so no error is reported. After that, we get a directory block without '.' and '..' but with a valid dentry. This may cause some code that relies on dot or dotdot (such as make_indexed_dir()) to crash. Therefore when ext4_read_dirblock() finds that the first directory block is a hole report that the filesystem is corrupted and return an error to avoid loading corrupted data from disk causing something bad.
- CVSS 3.1
- 5.5 MEDIUMCVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
- EPSS
- 0.23% probability · 14th percentile
- CISA KEV
- Not listed
- Affected
- linux/linux kernel
- Source
- 416baaa9-dc9f-4396-8d5f-8c081fb06d67
References
- https://git.kernel.org/stable/c/299bc6ffa57e04e74c6cce866d6c0741fb4897a1Patch
- https://git.kernel.org/stable/c/9771e3d8365ae1dd5e8846a204cb9af14e3e656aPatch
- https://git.kernel.org/stable/c/b609753cbbd38f8c0affd4956c0af178348523acPatch
- https://git.kernel.org/stable/c/c3893d9de8ee153baac56d127d844103488133b5Patch
- https://git.kernel.org/stable/c/d81d7e347d1f1f48a5634607d39eb90c161c8afePatch
- https://git.kernel.org/stable/c/de2a011a13a46468a6e8259db58b1b62071fe136Patch
- https://git.kernel.org/stable/c/e02f9941e8c011aa3eafa799def6a134ce06bcfaPatch
- https://git.kernel.org/stable/c/f9ca51596bbfd0f9c386dd1c613c394c78d9e5e6Patch
- https://lists.debian.org/debian-lts-announce/2024/10/msg00003.html
- https://lists.debian.org/debian-lts-announce/2025/01/msg00001.html
- https://cert-portal.siemens.com/productcert/html/ssa-265688.html
Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.