selinux: remove the BUG_ON() from selinux_skb_xfrm_sid()

Remove the BUG_ON() from selinux_skb_xfrm_sid() and propogate the
error code up to the caller.  Also check the return values in the
only caller function, selinux_skb_peerlbl_sid().

Signed-off-by: Paul Moore <pmoore@redhat.com>
Signed-off-by: Eric Paris <eparis@redhat.com>

2 files changed, 8 insertions, 5 deletions

diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c
index d3555bdf66af..4bc068b3773d 100644
--- a/security/selinux/hooks.c
+++ b/security/selinux/hooks.c
@@ -3722,8 +3722,12 @@ static int selinux_skb_peerlbl_sid(struct sk_buff *skb, u16 family, u32 *sid)
         u32 nlbl_sid;
         u32 nlbl_type;
 
-        selinux_skb_xfrm_sid(skb, &xfrm_sid);
-        selinux_netlbl_skbuff_getsid(skb, family, &nlbl_type, &nlbl_sid);
+        err = selinux_skb_xfrm_sid(skb, &xfrm_sid);
+        if (unlikely(err))
+                return -EACCES;
+        err = selinux_netlbl_skbuff_getsid(skb, family, &nlbl_type, &nlbl_sid);
+        if (unlikely(err))
+                return -EACCES;
 
         err = security_net_peersid_resolve(nlbl_sid, nlbl_type, xfrm_sid, sid);
         if (unlikely(err)) {
diff --git a/security/selinux/include/xfrm.h b/security/selinux/include/xfrm.h
index 60774bcf61b3..7605251936f5 100644
--- a/security/selinux/include/xfrm.h
+++ b/security/selinux/include/xfrm.h
@@ -76,10 +76,9 @@ static inline void selinux_xfrm_notify_policyload(void)
 }
 #endif
 
-static inline void selinux_skb_xfrm_sid(struct sk_buff *skb, u32 *sid)
+static inline int selinux_skb_xfrm_sid(struct sk_buff *skb, u32 *sid)
 {
-        int err = selinux_xfrm_decode_session(skb, sid, 0);
-        BUG_ON(err);
+        return selinux_xfrm_decode_session(skb, sid, 0);
 }
 
 #endif /* _SELINUX_XFRM_H_ */