Commit 588fb2c7 authored Oct 11, 2017 by Richard Guy Briggs Committed by James Morris Oct 20, 2017

capabilities: fix logic for effective root or real root

Now that the logic is inverted, it is much easier to see that both real
root and effective root conditions had to be met to avoid printing the
BPRM_FCAPS record with audit syscalls.  This meant that any setuid root
applications would print a full BPRM_FCAPS record when it wasn't
necessary, cluttering the event output, since the SYSCALL and PATH
records indicated the presence of the setuid bit and effective root user
id.

Require only one of effective root or real root to avoid printing the
unnecessary record.

Ref: commit 3fc689e9 ("Add audit_log_bprm_fcaps/AUDIT_BPRM_FCAPS")
See: https://github.com/linux-audit/audit-kernel/issues/16



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>
Acked-by: Paul Moore <paul@paul-moore.com>
Signed-off-by: James Morris <james.l.morris@oracle.com>

parent c0d1adef

security/commoncap.c

+2 −3

Original line number	Diff line number	Diff line
		@@ -770,7 +770,7 @@ static inline bool __is_setgid(struct cred new, const struct cred old)
		*
		* We do not bother to audit if 3 things are true:
		* 1) cap_effective has all caps
		* 2) we are root
		* 2) we became root OR are were already root
		* 3) root is supposed to have all caps (SECURE_NOROOT)
		* Since this is just a normal root execing a process.
		*
		@@ -783,8 +783,7 @@ static inline bool nonroot_raised_pE(struct cred *cred, kuid_t root)

		if (__cap_grew(effective, ambient, cred) &&
		!(__cap_full(effective, cred) &&
		__is_eff(root, cred) &&
		__is_real(root, cred) &&
		(__is_eff(root, cred) \|\| __is_real(root, cred)) &&
		root_privileged()))
		ret = true;
		return ret;

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