On Tue, Jan 18, 2022 at 12:59:25PM +0100, Christian Ehrhardt wrote:
> If so, any volunteers to commit this?
Done. Thanks for fixing this.
Two more things:
- We need a man page update. I think the missing documentation
of this feature was the reason that this bug was introduced.
- The strange M_EXT check with the XXX comment in ip input was the
reason I looked into this topic long time ago. I think a M_READONLY
would make the intention more obvious.
ok?
bluhm
Index: share/man/man9/mbuf.9
===================================================================
RCS file: /data/mirror/openbsd/cvs/src/share/man/man9/mbuf.9,v
retrieving revision 1.123
diff -u -p -r1.123 mbuf.9
--- share/man/man9/mbuf.9 8 Mar 2021 02:47:26 -0000 1.123
+++ share/man/man9/mbuf.9 13 Jan 2022 14:36:53 -0000
@@ -570,7 +570,7 @@ is freed.
Ensure that the data in the mbuf chain starting at the beginning of
the chain and ending at
.Fa len
-will be put in continuous memory region.
+will be put in continuous and writable memory region.
If memory must be allocated, then it will fail if the
.Fa len
argument is greater than MAXMCLBYTES.
Index: netinet/ip_input.c
===================================================================
RCS file: /data/mirror/openbsd/cvs/src/sys/netinet/ip_input.c,v
retrieving revision 1.364
diff -u -p -r1.364 ip_input.c
--- netinet/ip_input.c 22 Nov 2021 13:47:10 -0000 1.364
+++ netinet/ip_input.c 18 Jan 2022 12:42:14 -0000
@@ -415,7 +415,7 @@ ip_input_if(struct mbuf **mp, int *offp,
if (ipmforwarding && ip_mrouter[ifp->if_rdomain]) {
int error;
- if (m->m_flags & M_EXT) {
+ if (M_READONLY(m)) {
if ((m = *mp = m_pullup(m, hlen)) == NULL) {
ipstat_inc(ips_toosmall);
goto bad;
@@ -532,7 +532,7 @@ ip_ours(struct mbuf **mp, int *offp, int
* but it's not worth the time; just let them time out.)
*/
if (ip->ip_off &~ htons(IP_DF | IP_RF)) {
- if (m->m_flags & M_EXT) { /* XXX */
+ if (M_READONLY(m)) {
if ((m = *mp = m_pullup(m, hlen)) == NULL) {
ipstat_inc(ips_toosmall);
return IPPROTO_DONE;
