NetSight
medium5.5

CVE-2021-47579

In the Linux kernel, the following vulnerability has been resolved: ovl: fix warning in ovl_create_real() Syzbot triggered the following warning in ovl_workdir…

Impact

In the Linux kernel, the following vulnerability has been resolved: ovl: fix warning in ovl_create_real() Syzbot triggered the following warning in ovl_workdir_create() -> ovl_create_real(): if (!err && WARN_ON(!newdentry->d_inode)) { The reason is that the cgroup2 filesystem returns from mkdir without instantiating the new dentry. Weird filesystems such as this will be rejected by overlayfs at a later stage during setup, but to prevent such a warning, call ovl_mkdir_real() directly from ovl_workdir_create() and reject this case early.

Affected products

VendorProductAffected versions
LinuxLinux Kernel
before 4.19.222
from 4.20 before 5.4.168
from 5.5 before 5.10.88
from 5.11 before 5.15.11

References