| Name | 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. |
| Source | CVE (at NVD; CERT, ENISA, LWN, oss-sec, fulldisc, Debian ELTS, Red Hat, Ubuntu, Gentoo, SUSE bugzilla/CVE, GitHub advisories/code/issues, web search, more) |
| References | DLA-3912-1, DLA-4008-1 |
The table below lists information on source packages.
| Source Package | Release | Version | Status |
|---|---|---|---|
| linux (PTS) | bullseye | 5.10.223-1 | vulnerable |
| bullseye (security) | 5.10.244-1 | fixed | |
| bookworm | 6.1.148-1 | fixed | |
| bookworm (security) | 6.1.158-1 | fixed | |
| trixie | 6.12.57-1 | fixed | |
| trixie (security) | 6.12.48-1 | fixed | |
| forky | 6.16.12-2 | fixed | |
| sid | 6.17.8-1 | fixed | |
| linux-6.1 (PTS) | bullseye (security) | 6.1.153-1~deb11u1 | fixed |
The information below is based on the following data on fixed versions.
| Package | Type | Release | Fixed Version | Urgency | Origin | Debian Bugs |
|---|---|---|---|---|---|---|
| linux | source | bullseye | 5.10.226-1 | DLA-3912-1 | ||
| linux | source | bookworm | 6.1.106-1 | |||
| linux | source | (unstable) | 6.10.3-1 | |||
| linux-6.1 | source | bullseye | 6.1.119-1~deb11u1 | DLA-4008-1 |
https://git.kernel.org/linus/f9ca51596bbfd0f9c386dd1c613c394c78d9e5e6 (6.11-rc1)