Re: [PATCH V4 06/10] 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(a)hallyn.com&gt; Signed-off-by: Richard Guy Briggs <rgb(a)redhat.com&gt; Reviewed-by: Serge Hallyn <serge(a)hallyn.com&gt; Acked-by: James Morris <james.l.morris(a)oracle.com&gt;

--- security/commoncap.c | 50 ++++++++++++++++++++++++++++++-------------------- 1 files changed, 30 insertions(+), 20 deletions(-) diff --git a/security/commoncap.c b/security/commoncap.c index d37ebec..eae7431 100644 --- a/security/commoncap.c +++ b/security/commoncap.c @@ -527,6 +527,32 @@ 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 @@ -604,26 +630,10 @@ 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); -- 1.7.1