slirp: Fix access to freed memory
if_start() goes through the slirp->if_fastq and slirp->if_batchq
list of pending messages, and accesses ifm->ifq_so->so_nqueued of its
elements if ifm->ifq_so != NULL. When freeing a socket, we thus need
to make sure that any pending message for this socket does not refer
to the socket any more.
Signed-off-by: Samuel Thibault <samuel.thibault@ens-lyon.org>
Tested-by: Brian Candler <b.candler@pobox.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
diff --git a/slirp/socket.c b/slirp/socket.c
index 280050a..6c18971 100644
--- a/slirp/socket.c
+++ b/slirp/socket.c
@@ -66,6 +66,23 @@
sofree(struct socket *so)
{
Slirp *slirp = so->slirp;
+ struct mbuf *ifm;
+
+ for (ifm = (struct mbuf *) slirp->if_fastq.qh_link;
+ (struct quehead *) ifm != &slirp->if_fastq;
+ ifm = ifm->ifq_next) {
+ if (ifm->ifq_so == so) {
+ ifm->ifq_so = NULL;
+ }
+ }
+
+ for (ifm = (struct mbuf *) slirp->if_batchq.qh_link;
+ (struct quehead *) ifm != &slirp->if_batchq;
+ ifm = ifm->ifq_next) {
+ if (ifm->ifq_so == so) {
+ ifm->ifq_so = NULL;
+ }
+ }
if (so->so_emu==EMU_RSH && so->extra) {
sofree(so->extra);
