[ECOS] Bugs in FreeBSD stack fixed ...

[Thomas BINDER <Thomas dot Binder at frequentis dot com>]

Hi!

The attached patch fixes 2 bugs in the FreeBSD stack.

The first problem is that the alloc method of the fixed mempool is called from an interrupt, the second is a NULL pointer dereferenciation in case m_copy failed. The NULL pointer problem was also discussed on the FreeBSD list (April 2003).

best regards,
Tom
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diff --exclude CVS -NauU5 -r /home_vie1/tbinder/ecos-anonymous/ecos/packages/net/bsd_tcpip/current/ChangeLog ./net/bsd_tcpip/current/ChangeLog
--- /home_vie1/tbinder/ecos-anonymous/ecos/packages/net/bsd_tcpip/current/ChangeLog	Sun Sep 14 00:00:37 2003
+++ ./net/bsd_tcpip/current/ChangeLog	Wed Sep 17 18:09:06 2003
@@ -1,5 +1,15 @@
+2003-09-17  Reinhard Jessich  <Reinhard.Jessich@frequentis.com>
+
+	* src/sys/kern/uipc_mbuf.c: Now using flags (how) argument in call to
+	cyg_net_mbuf_alloc, to avoid a (blocking) call to alloc method of mempool 
+	during interrupts. This problem occurred under heavy IP traffic in case the 
+	mempool became empty (alloc blocked).
+	* src/sys/net/if_ethersubr.c: Avoid dereferencing NULL pointer in case of
+	failing m_copy. Note that this problem was (at least sometimes) hidden 
+	due to the bug in uipc_mbuf.c (described above).
+
 2003-09-08  Andrew Lunn  <andrew.lunn@ascom.ch>
 
 	* src/ecos/support.c (read_random): New function which is needed
 	when CYGSEM_NET_RANDOMID is enabled.
 	* include/sys/param.h: Prototype for new function.
diff --exclude CVS -NauU5 -r /home_vie1/tbinder/ecos-anonymous/ecos/packages/net/bsd_tcpip/current/src/sys/kern/uipc_mbuf.c ./net/bsd_tcpip/current/src/sys/kern/uipc_mbuf.c
--- /home_vie1/tbinder/ecos-anonymous/ecos/packages/net/bsd_tcpip/current/src/sys/kern/uipc_mbuf.c	Wed Sep 17 17:54:06 2003
+++ ./net/bsd_tcpip/current/src/sys/kern/uipc_mbuf.c	Wed Sep 17 17:35:41 2003
@@ -137,11 +137,11 @@
 {
 	struct mbuf *p;
 	int i;
 
 	for (i = 0; i < nmb; i++) {
-            p = (struct mbuf *)cyg_net_mbuf_alloc(0, 0);
+            p = (struct mbuf *)cyg_net_mbuf_alloc(0, how);
             if (p != (struct mbuf *)0) {
 		((struct mbuf *)p)->m_next = mmbfree;
 		mmbfree = (struct mbuf *)p;
                 mbstat.m_mbufs++;
                 mbtypes[MT_FREE]++;
diff --exclude CVS -NauU5 -r /home_vie1/tbinder/ecos-anonymous/ecos/packages/net/bsd_tcpip/current/src/sys/net/if_ethersubr.c ./net/bsd_tcpip/current/src/sys/net/if_ethersubr.c
--- /home_vie1/tbinder/ecos-anonymous/ecos/packages/net/bsd_tcpip/current/src/sys/net/if_ethersubr.c	Wed Sep 17 17:54:07 2003
+++ ./net/bsd_tcpip/current/src/sys/net/if_ethersubr.c	Wed Sep 17 17:51:33 2003
@@ -337,10 +337,15 @@
 	 * reasons and compatibility with the original behavior.
 	 */
 	if ((ifp->if_flags & IFF_SIMPLEX) && (loop_copy != -1)) {
 		if ((m->m_flags & M_BCAST) || (loop_copy > 0)) {
 			struct mbuf *n = m_copy(m, 0, (int)M_COPYALL);
+            
+            if ( n == 0 ) {
+                error = 0;
+                goto bad;
+            }
 
 			(void) if_simloop(ifp, n, dst->sa_family, hlen);
 		} else if (bcmp(eh->ether_dhost,
 		    eh->ether_shost, ETHER_ADDR_LEN) == 0) {
 			(void) if_simloop(ifp, m, dst->sa_family, hlen);

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