In FreeBSD 12.2-STABLE before r368969, 11.4-STABLE before r369047, 12.2-RELEASE before p3, 12.1-RELEASE before p13 and 11.4-RELEASE before p7 several file systems were not properly initializing the d_off field of the dirent structures returned by VOP_READDIR. In particular, tmpfs(5), smbfs(5), autofs(5) and mqueuefs(5) were failing to do so. As a result, eight uninitialized kernel stack bytes may be leaked to userspace by these file systems.
Source: https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2020-25578
Reference (s):
- https://security.netapp.com/advisory/ntap-20210423-0002/
- https://security.FreeBSD.org/advisories/FreeBSD-SA-21:01.fsdisclosure.asc
- URL: https://security.FreeBSD.org/advisories/FreeBSD-SA-21:01.fsdisclosure.asc