[Qemu-devel] [PATCH] slirp: Propagate host TCP RST to the guest.

["Edgar E. Iglesias" <edgar.iglesias@axis.com>]

Hi,

Jason found a bug in teh slirp TCP RST code. Here is a patch to fix it.
Is this OK to commit?

Best regards
-- 
Edgar E. Iglesias
Axis Communications AB

When the host aborts (RST) it's side of a TCP connection we need to
propagate that RST to the guest. The current code can leave such guest
connections dangling forever. Spotted by Jason Wessel.

diff --git a/slirp/socket.c b/slirp/socket.c
index 75003af..bb10d69 100644
--- a/slirp/socket.c
+++ b/slirp/socket.c
@@ -165,9 +165,21 @@ soread(so)
 		if (nn < 0 && (errno == EINTR || errno == EAGAIN))
 			return 0;
 		else {
+			int err;
+			socklen_t slen = sizeof err;
+
+			err = errno;
+			if (nn == 0)
+				getsockopt(so->s, SOL_SOCKET, SO_ERROR,
+					   &err, &slen);
+
 			DEBUG_MISC((dfd, " --- soread() disconnected, nn = %d, errno = %d-%s\n", nn, errno,strerror(errno)));
 			sofcantrcvmore(so);
-			tcp_sockclosed(sototcpcb(so));
+			if (err == ECONNRESET
+			    || err == ENOTCONN || err == EPIPE)
+				tcp_drop(sototcpcb(so), err);
+			else
+				tcp_sockclosed(sototcpcb(so));
 			return -1;
 		}
 	}