In the Linux kernel, the following vulnerability has been resolved:

selinux: always fill AVC decision in avc_has_perm_noaudit()

avc_has_perm_noaudit() is documented to return a copy of the access
decision in @avd, but its early return for an empty requested permission
set leaves the buffer untouched.  All callers pass an uninitialized
stack variable and afterwards feed it to avc_audit(), and the inode hook
even stores it in the per-task decision cache.

Fill in a deny-all, audit-all decision, similar to avd_init(), so every
caller receives a defined value at no cost on the hot path.