xnu-792.22.5.tar.gz

[apple/xnu.git] / bsd / net / if_stf.c

diff --git a/bsd/net/if_stf.c b/bsd/net/if_stf.c
index 6bf96e3497c2aeef4a6ead6c8325856709ca3fb0..c9d646ea1d05d2751819281e499ea091225abf1a 100644 (file)
--- a/bsd/net/if_stf.c
+++ b/bsd/net/if_stf.c
@@ -427,8 +427,10 @@ stf_pre_output(
 
        if (m->m_len < sizeof(*ip6)) {
                m = m_pullup(m, sizeof(*ip6));
-               if (!m)
+               if (!m) {
+                       *m0 = NULL; /* makes sure this won't be double freed */
                        return ENOBUFS;
+               }
        }
        ip6 = mtod(m, struct ip6_hdr *);
        tos = (ntohl(ip6->ip6_flow) >> 20) & 0xff;
@@ -466,8 +468,10 @@ stf_pre_output(
        M_PREPEND(m, sizeof(struct ip), M_DONTWAIT);
        if (m && m->m_len < sizeof(struct ip))
                m = m_pullup(m, sizeof(struct ip));
-       if (m == NULL)
+       if (m == NULL) {
+               *m0 = NULL; 
                return ENOBUFS;
+       }
        ip = mtod(m, struct ip *);
 
        bzero(ip, sizeof(*ip));
@@ -507,6 +511,7 @@ stf_pre_output(
        if (error == 0)
                return EJUSTRETURN;
 
+       *m0 = NULL; 
        return error;
 }