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
7.8 HIGH (v3.1, CNA)CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
from 3a17ca864baffc0c6f6e8aad525aa4365775a193 before d81d7e347d1f1f48a5634607d39eb90c161c8afe; from 4e19d6b65fb4fc42e352ce9883649e049da14743 before e02f9941e8c011aa3eafa799def6a134ce06bcfa; from 4e19d6b65fb4fc42e352ce9883649e049da14743 before de2a011a13a46468a6e8259db58b1b62071fe136; from 4e19d6b65fb4fc42e352ce9883649e049da14743 before 9771e3d8365ae1dd5e8846a204cb9af14e3e656a; from 4e19d6b65fb4fc42e352ce9883649e049da14743 before b609753cbbd38f8c0affd4956c0af178348523ac; from 4e19d6b65fb4fc42e352ce9883649e049da14743 before c3893d9de8ee153baac56d127d844103488133b5; from 4e19d6b65fb4fc42e352ce9883649e049da14743 before 299bc6ffa57e04e74c6cce866d6c0741fb4897a1; from 4e19d6b65fb4fc42e352ce9883649e049da14743 before f9ca51596bbfd0f9c386dd1c613c394c78d9e5e6; and 9 more ranges
from 4.9.187 before 4.10; from 4.14.135 before 4.15; from 4.19.62 before 4.19.320; from 5.1.21 before 5.2; from 5.2.4 before 5.4.282; from 5.5 before 5.10.224; from 5.11 before 5.15.165; from 5.16 before 6.1.103; and 2 more ranges
The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.
Printed from infosecsignals.com. Every record links back to the agency that published it.
Your cookie choices
We use essential cookies to run this site, and, only with your consent, an advertising cookie from Google to measure whether our ads lead to sign-ups and subscriptions. See our for details.