[PATCH GHAK16 V5 07/10] capabilities: remove a layer of conditional logic

From: Richard Guy Briggs
Date: Wed Oct 11 2017 - 20:59:13 EST


Remove a layer of conditional logic to make the use of conditions
easier to read and analyse.

Signed-off-by: Richard Guy Briggs <rgb@xxxxxxxxxx>
Reviewed-by: Serge Hallyn <serge@xxxxxxxxxx>
Acked-by: James Morris <james.l.morris@xxxxxxxxxx>
Acked-by: Kees Cook <keescook@xxxxxxxxxxxx>
Okay-ished-by: Paul Moore <paul@xxxxxxxxxxxxxx>
---
security/commoncap.c | 23 ++++++++++-------------
1 file changed, 10 insertions(+), 13 deletions(-)

diff --git a/security/commoncap.c b/security/commoncap.c
index d7f0cbd..eac70e2 100644
--- a/security/commoncap.c
+++ b/security/commoncap.c
@@ -781,13 +781,12 @@ 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;
- }
- }
+ if (__cap_grew(effective, ambient, cred) &&
+ (!__cap_full(effective, cred) ||
+ !__is_eff(root, cred) ||
+ !__is_real(root, cred) ||
+ !root_privileged()))
+ ret = true;
return ret;
}

@@ -880,13 +879,11 @@ int cap_bprm_set_creds(struct linux_binprm *bprm)

/* Check for privilege-elevated exec. */
bprm->cap_elevated = 0;
- if (is_setid) {
+ if (is_setid ||
+ (!__is_real(root_uid, new) &&
+ (effective ||
+ __cap_grew(permitted, ambient, new))))
bprm->cap_elevated = 1;
- } else if (!__is_real(root_uid, new)) {
- if (effective ||
- __cap_grew(permitted, ambient, new))
- bprm->cap_elevated = 1;
- }

return 0;
}
--
1.8.3.1