From 70169420f555210147f3cab74bb0f6debd488bdb Mon Sep 17 00:00:00 2001 From: "Eric W. Biederman" Date: Thu, 17 Nov 2016 01:38:35 -0600 Subject: [PATCH] exec: Don't reset euid and egid when the tracee has CAP_SETUID Don't reset euid and egid when the tracee has CAP_SETUID in it's user namespace. I punted on relaxing this permission check long ago but now that I have read this code closely it is clear it is safe to test against CAP_SETUID in the user namespace. Signed-off-by: "Eric W. Biederman" --- security/commoncap.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/security/commoncap.c b/security/commoncap.c index 8df676fbd393..feb6044f701d 100644 --- a/security/commoncap.c +++ b/security/commoncap.c @@ -550,7 +550,7 @@ skip: !cap_issubset(new->cap_permitted, old->cap_permitted)) && bprm->unsafe & ~LSM_UNSAFE_PTRACE_CAP) { /* downgrade; they get no more than they had, and maybe less */ - if (!capable(CAP_SETUID) || + if (!ns_capable(new->user_ns, CAP_SETUID) || (bprm->unsafe & LSM_UNSAFE_NO_NEW_PRIVS)) { new->euid = new->uid; new->egid = new->gid; -- 2.20.1