CVE-2024-42304
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.
Predictions
Heuristic predictions, AS-IS, for prioritization only.
Mitigations
Vendor advisory: debian — https://security-tracker.debian.org/tracker/CVE-2024-42304
Vendor advisory: suse — https://www.suse.com/security/cve/CVE-2024-42304.html
Vendor advisory: 416baaa9-dc9f-4396-8d5f-8c081fb06d67 — https://git.kernel.org/stable/c/f9ca51596bbfd0f9c386dd1c613c394c78d9e5e6
Vendor advisory: 416baaa9-dc9f-4396-8d5f-8c081fb06d67 — https://git.kernel.org/stable/c/e02f9941e8c011aa3eafa799def6a134ce06bcfa
Vendor advisory: 416baaa9-dc9f-4396-8d5f-8c081fb06d67 — https://git.kernel.org/stable/c/de2a011a13a46468a6e8259db58b1b62071fe136
Vendor advisory: 416baaa9-dc9f-4396-8d5f-8c081fb06d67 — https://git.kernel.org/stable/c/d81d7e347d1f1f48a5634607d39eb90c161c8afe
Vendor advisory: 416baaa9-dc9f-4396-8d5f-8c081fb06d67 — https://git.kernel.org/stable/c/c3893d9de8ee153baac56d127d844103488133b5
Vendor advisory: 416baaa9-dc9f-4396-8d5f-8c081fb06d67 — https://git.kernel.org/stable/c/b609753cbbd38f8c0affd4956c0af178348523ac
Vendor advisory: 416baaa9-dc9f-4396-8d5f-8c081fb06d67 — https://git.kernel.org/stable/c/9771e3d8365ae1dd5e8846a204cb9af14e3e656a
Vendor advisory: 416baaa9-dc9f-4396-8d5f-8c081fb06d67 — https://git.kernel.org/stable/c/299bc6ffa57e04e74c6cce866d6c0741fb4897a1
Vendor advisory: redhat — https://access.redhat.com/errata/RHSA-2025:6966
OS impact
| OS | Version | Status | Fixed in |
|---|---|---|---|
| rhel | 9 | fixed | |
| sles | affected | | |
| debian | bookworm | fixed | 6.1.106-1 |
| debian | bullseye | fixed | 5.10.226-1 |
| debian | forky | fixed | 6.10.3-1 |
| debian | sid | fixed | 6.10.3-1 |
| debian | trixie | fixed | 6.10.3-1 |
| linux-kernel | affected | 4.10 |
References
- https://access.redhat.com/errata/RHSA-2025:6966
- https://git.kernel.org/stable/c/299bc6ffa57e04e74c6cce866d6c0741fb4897a1
- https://git.kernel.org/stable/c/9771e3d8365ae1dd5e8846a204cb9af14e3e656a
- https://git.kernel.org/stable/c/b609753cbbd38f8c0affd4956c0af178348523ac
- https://git.kernel.org/stable/c/c3893d9de8ee153baac56d127d844103488133b5
- https://git.kernel.org/stable/c/d81d7e347d1f1f48a5634607d39eb90c161c8afe
- https://git.kernel.org/stable/c/de2a011a13a46468a6e8259db58b1b62071fe136
- https://git.kernel.org/stable/c/e02f9941e8c011aa3eafa799def6a134ce06bcfa
- https://git.kernel.org/stable/c/f9ca51596bbfd0f9c386dd1c613c394c78d9e5e6
- 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
- https://www.suse.com/security/cve/CVE-2024-42304.html
- https://security-tracker.debian.org/tracker/CVE-2024-42304
Verify integrity in audit chain (admin only). AS-IS.