[PATCH 1/1] security: handle secureexec with filesystem capabilities

[Serge E . Hallyn]

A secure exec is required if euid!=uid, and, correspondingly,
if the executable's file capability set was not empty and the
process is not owned by (real uid) root.

Signed-off-by: Serge E. Hallyn <serue@xxxxxxxxxx>
---
 security/commoncap.c |   14 +++++++++-----
 1 files changed, 9 insertions(+), 5 deletions(-)

diff --git a/security/commoncap.c b/security/commoncap.c
index 6bf030d..b1777a9 100644
--- a/security/commoncap.c
+++ b/security/commoncap.c
@@ -265,11 +265,15 @@ void cap_bprm_apply_creds (struct linux_
 
 int cap_bprm_secureexec (struct linux_binprm *bprm)
 {
-	/* If/when this module is enhanced to incorporate capability
-	   bits on files, the test below should be extended to also perform a 
-	   test between the old and new capability sets.  For now,
-	   it simply preserves the legacy decision algorithm used by
-	   the old userland. */
+	if (current->uid != 0) {
+		if (!cap_isclear(bprm->cap_effective))
+			return 1;
+		if (!cap_isclear(bprm->cap_permitted))
+			return 1;
+		if (!cap_isclear(bprm->cap_inheritable))
+			return 1;
+	}
+
 	return (current->euid != current->uid ||
 		current->egid != current->gid);
 }
-- 
1.4.2

-
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