From 8d18e582f87998e2ae1d7ce8729467d1721c20ac Mon Sep 17 00:00:00 2001 From: Christian Brauner Date: Fri, 8 Feb 2019 15:11:46 +0100 Subject: [PATCH] caps: check uid and euid When we are running inside of a user namespace getuid() will return a non-zero uid. So let's check euid as well to make sure we correctly drop capabilities Signed-off-by: Christian Brauner --- src/lxc/caps.c | 6 ++---- 1 file changed, 2 insertions(+), 4 deletions(-) diff --git a/src/lxc/caps.c b/src/lxc/caps.c index 5638c712e..1346ec74f 100644 --- a/src/lxc/caps.c +++ b/src/lxc/caps.c @@ -154,8 +154,7 @@ int lxc_ambient_caps_up(void) int last_cap = CAP_LAST_CAP; char *cap_names = NULL; - /* When we are run as root, we don't want to play with the capabilities. */ - if (!getuid()) + if (!getuid() || geteuid()) return 0; caps = cap_get_proc(); @@ -222,8 +221,7 @@ int lxc_ambient_caps_down(void) cap_t caps; cap_value_t cap; - /* When we are run as root, we don't want to play with the capabilities. */ - if (!getuid()) + if (!getuid() || geteuid()) return 0; ret = prctl(PR_CAP_AMBIENT, PR_CAP_AMBIENT_CLEAR_ALL, 0, 0, 0); -- 2.47.2