From: Matthew Garrett <mj...@srcf.ucam.org> uswsusp allows a user process to dump and then restore kernel state, which makes it possible to modify the running kernel. Disable this if the kernel is locked down.
Signed-off-by: David Howells <dhowe...@redhat.com> Signed-off-by: Matthew Garrett <mj...@google.com> cc: linux...@vger.kernel.org Cc: pa...@ucw.cz Cc: r...@rjwysocki.net --- kernel/power/user.c | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/kernel/power/user.c b/kernel/power/user.c index 2d8b60a3c86b..8a8d7f1c8fbb 100644 --- a/kernel/power/user.c +++ b/kernel/power/user.c @@ -24,6 +24,7 @@ #include <linux/console.h> #include <linux/cpu.h> #include <linux/freezer.h> +#include <linux/security.h> #include <linux/uaccess.h> @@ -52,6 +53,9 @@ static int snapshot_open(struct inode *inode, struct file *filp) if (!hibernation_available()) return -EPERM; + if (security_is_locked_down(LOCKDOWN_HIBERNATION)) + return -EPERM; + lock_system_sleep(); if (!atomic_add_unless(&snapshot_device_available, -1, 0)) { -- 2.22.0.410.gd8fdbe21b5-goog