X-Git-Url: https://err.no/cgi-bin/gitweb.cgi?a=blobdiff_plain;f=security%2Fcommoncap.c;h=ea61bc73f6d3c4d1ecfe9d81964342b8cd306d74;hb=dfc5aa00cbe888d3a9ea97775bbac74cb1c1a1d8;hp=5bc1895f3f9ce0997afbf59448ad0053cb4aa56b;hpb=03bbe082cffc4533f6557bf23f0c672307067246;p=linux-2.6

diff --git a/security/commoncap.c b/security/commoncap.c
index 5bc1895f3f..ea61bc73f6 100644
--- a/security/commoncap.c
+++ b/security/commoncap.c
@@ -59,6 +59,12 @@ int cap_netlink_recv(struct sk_buff *skb, int cap)
 
 EXPORT_SYMBOL(cap_netlink_recv);
 
+/*
+ * NOTE WELL: cap_capable() cannot be used like the kernel's capable()
+ * function.  That is, it has the reverse semantics: cap_capable()
+ * returns 0 when a task has a capability, but the kernel's capable()
+ * returns 1 for this case.
+ */
 int cap_capable (struct task_struct *tsk, int cap)
 {
 	/* Derived from include/linux/sched.h:capable. */
@@ -107,10 +113,11 @@ static inline int cap_block_setpcap(struct task_struct *target)
 static inline int cap_inh_is_capped(void)
 {
 	/*
-	 * return 1 if changes to the inheritable set are limited
-	 * to the old permitted set.
+	 * Return 1 if changes to the inheritable set are limited
+	 * to the old permitted set. That is, if the current task
+	 * does *not* possess the CAP_SETPCAP capability.
 	 */
-	return !cap_capable(current, CAP_SETPCAP);
+	return (cap_capable(current, CAP_SETPCAP) != 0);
 }
 
 #else /* ie., ndef CONFIG_SECURITY_FILE_CAPABILITIES */