Entreprise française de cybersécurité depuis 2004
☎ 03 60 47 09 81 - info@securiteinfo.com
☎ 03 60 47 09 81 - info@securiteinfo.com
In the Linux kernel, the following vulnerability has been resolved:ocfs2: fix slab-use-after-free due to dangling pointer dqi_privWhen mounting ocfs2 and then remounting it as read-only, aslab-use-after-free occurs after the user uses a syscall toquota_getnextquota. Specifically, sb_dqinfo(sb, type)->dqi_priv is thedangling pointer.During the remounting process, the pointer dqi_priv is freed but is neverset as null leaving it to be accessed. Additionally, the read-only optionfor remounting sets the DQUOT_SUSPENDED flag instead of setting theDQUOT_USAGE_ENABLED flags. Moreover, later in the process of getting thenext quota, the function ocfs2_get_next_id is called and only checks thequota usage flags and not the quota suspended flags.To fix this, I set dqi_priv to null when it is freed after remounting withread-only and put a check for DQUOT_SUSPENDED in ocfs2_get_next_id.[akpm@linux-foundation.org: coding-style cleanups]
No PoCs from references.
- https://github.com/fkie-cad/nvd-json-data-feeds
- https://github.com/oogasawa/Utility-security
- https://github.com/w4zu/Debian_security