Guard against NULL pointer dereferencing.

diff --git a/test.c b/test.c
index fcf0c794883e1f4e6fe06d6700c9a158e629f1f6..b5d64a3eb3ba698c8c763010131fbd386df5fbd0 100644 (file)
--- a/test.c
+++ b/test.c
@@ -106,7 +106,7 @@ int main(int argc, char *argv[]) {
        struct timeval timeout = utcp_timeout(u);
 
        while(dir) {
-               size_t max = utcp_get_sndbuf_free(c);
+               size_t max = c ? utcp_get_sndbuf_free(c) : 0;
                if(max > sizeof buf)
                        max = sizeof buf;
 

diff --git a/utcp.c b/utcp.c
index 1d8f4b2a9e3a7865e8813d9032d6510b51cb3a8c..21fbea6c4eea4df28380098bdff43edb33441775 100644 (file)
--- a/utcp.c
+++ b/utcp.c
@@ -1154,63 +1154,71 @@ void utcp_exit(struct utcp *utcp) {
 }
 
 uint16_t utcp_get_mtu(struct utcp *utcp) {
-       return utcp->mtu;
+       return utcp ? utcp->mtu : 0;
 }
 
 void utcp_set_mtu(struct utcp *utcp, uint16_t mtu) {
        // TODO: handle overhead of the header
-       utcp->mtu = mtu;
+       if(utcp)
+               utcp->mtu = mtu;
 }
 
 int utcp_get_user_timeout(struct utcp *u) {
-       return u->timeout;
+       return u ? u->timeout : 0;
 }
 
 void utcp_set_user_timeout(struct utcp *u, int timeout) {
-       u->timeout = timeout;
+       if(u)
+               u->timeout = timeout;
 }
 
 size_t utcp_get_sndbuf(struct utcp_connection *c) {
-       return c->sndbuf.maxsize;
+       return c ? c->sndbuf.maxsize : 0;
 }
 
 size_t utcp_get_sndbuf_free(struct utcp_connection *c) {
-       if(c->state == ESTABLISHED || c->state == CLOSE_WAIT)
+       if(c && (c->state == ESTABLISHED || c->state == CLOSE_WAIT))
                return buffer_free(&c->sndbuf);
        else
                return 0;
 }
 
 void utcp_set_sndbuf(struct utcp_connection *c, size_t size) {
+       if(!c)
+               return;
        c->sndbuf.maxsize = size;
        if(c->sndbuf.maxsize != size)
                c->sndbuf.maxsize = -1;
 }
 
 bool utcp_get_nodelay(struct utcp_connection *c) {
-       return c->nodelay;
+       return c ? c->nodelay : false;
 }
 
 void utcp_set_nodelay(struct utcp_connection *c, bool nodelay) {
-       c->nodelay = nodelay;
+       if(c)
+               c->nodelay = nodelay;
 }
 
 bool utcp_get_keepalive(struct utcp_connection *c) {
-       return c->keepalive;
+       return c ? c->keepalive : false;
 }
 
 void utcp_set_keepalive(struct utcp_connection *c, bool keepalive) {
-       c->keepalive = keepalive;
+       if(c)
+               c->keepalive = keepalive;
 }
 
 size_t utcp_get_outq(struct utcp_connection *c) {
-       return seqdiff(c->snd.nxt, c->snd.una);
+       return c ? seqdiff(c->snd.nxt, c->snd.una) : 0;
 }
 
 void utcp_set_recv_cb(struct utcp_connection *c, utcp_recv_t recv) {
-       c->recv = recv;
+       if(c)
+               c->recv = recv;
 }
 
 void utcp_set_poll_cb(struct utcp_connection *c, utcp_poll_t poll) {
-       c->poll = poll;
+       if(c)
+               c->poll = poll;
 }