In the Linux kernel, the following vulnerability has been resolved: sysctl: always initialize iuid/igid Always initialize iuid/igid inside the sysfs core so setownership() can safely skip setting them. Commit 5ec27ec735ba ("fs/proc/procsysctl.c: fix the default values of iuid/igid on /proc/sys inodes.") added defaults for iuid/igid when setownership() was not implemented. It also missed adjusting netctlsetownership() to use the same default values in case the computation of a better value failed.