capabilities: move audit log decision to function
Move the audit log decision logic to its own function to isolate the
complexity in one place.
Suggested-by: Serge Hallyn <serge@hallyn.com>
Signed-off-by: Richard Guy Briggs <rgb@redhat.com>
Reviewed-by: Serge Hallyn <serge@hallyn.com>
Acked-by: James Morris <james.l.morris@oracle.com>
Acked-by: Kees Cook <keescook@chromium.org>
Okay-ished-by: Paul Moore <paul@paul-moore.com>
Signed-off-by: James Morris <james.l.morris@oracle.com>
diff --git a/security/commoncap.c b/security/commoncap.c
index 421f743..d7f0cbd 100644
--- a/security/commoncap.c
+++ b/security/commoncap.c
@@ -765,6 +765,32 @@ static inline bool __is_setuid(struct cred *new, const struct cred *old)
static inline bool __is_setgid(struct cred *new, const struct cred *old)
{ return !gid_eq(new->egid, old->gid); }
+/*
+ * Audit candidate if current->cap_effective is set
+ *
+ * We do not bother to audit if 3 things are true:
+ * 1) cap_effective has all caps
+ * 2) we are root
+ * 3) root is supposed to have all caps (SECURE_NOROOT)
+ * Since this is just a normal root execing a process.
+ *
+ * Number 1 above might fail if you don't have a full bset, but I think
+ * that is interesting information to audit.
+ */
+static inline bool nonroot_raised_pE(struct cred *cred, kuid_t root)
+{
+ bool ret = false;
+
+ if (__cap_grew(effective, ambient, cred)) {
+ if (!__cap_full(effective, cred) ||
+ !__is_eff(root, cred) || !__is_real(root, cred) ||
+ !root_privileged()) {
+ ret = true;
+ }
+ }
+ return ret;
+}
+
/**
* cap_bprm_set_creds - Set up the proposed credentials for execve().
* @bprm: The execution parameters, including the proposed creds
@@ -841,26 +867,10 @@ int cap_bprm_set_creds(struct linux_binprm *bprm)
if (WARN_ON(!cap_ambient_invariant_ok(new)))
return -EPERM;
- /*
- * Audit candidate if current->cap_effective is set
- *
- * We do not bother to audit if 3 things are true:
- * 1) cap_effective has all caps
- * 2) we are root
- * 3) root is supposed to have all caps (SECURE_NOROOT)
- * Since this is just a normal root execing a process.
- *
- * Number 1 above might fail if you don't have a full bset, but I think
- * that is interesting information to audit.
- */
- if (__cap_grew(effective, ambient, new)) {
- if (!__cap_full(effective, new) ||
- !__is_eff(root_uid, new) || !__is_real(root_uid, new) ||
- !root_privileged()) {
- ret = audit_log_bprm_fcaps(bprm, new, old);
- if (ret < 0)
- return ret;
- }
+ if (nonroot_raised_pE(new, root_uid)) {
+ ret = audit_log_bprm_fcaps(bprm, new, old);
+ if (ret < 0)
+ return ret;
}
new->securebits &= ~issecure_mask(SECURE_KEEP_CAPS);