CVE-2024-50191medium

CVE-2024-50191: medium-severity vulnerability in Linux

ext4: don't set SB_RDONLY after filesystem errors

Published · Updated

13Vexday Risk Score

No sign of exploitation. No public exploitation artifact known so far.

ssvc Trackcvss 5.5epss 0.2%
exploitation probability
0.2%top 90% of all CVEs
observed exploitation
nono source reports it
In the Linux kernel, the following vulnerability has been resolved: ext4: don't set SB_RDONLY after filesystem errors When the filesystem is mounted with errors=remount-ro, we were setting SB_RDONLY flag to stop all filesystem modifications. We knew this misses proper locking (sb->s_umount) and does not go through proper filesystem remount procedure but it has been the way this worked since early ext2 days and it was good enough for catastrophic situation damage mitigation. Recently, syzbot has found a way (see link) to trigger warnings in filesystem freezing because the code got confused by SB_RDONLY changing under its hands. Since these days we set EXT4_FLAGS_SHUTDOWN on the superblock which is enough to stop all filesystem modifications, modifying SB_RDONLY shouldn't be needed. So stop doing that.
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Affected products
Linux · Linux