From: David Woodhouse <dwmw2@infradead.org>
Date: Thu, 8 Jul 2021 19:30:38 +0000 (+0100)
Subject: Check eventfd read/write returns
X-Git-Tag: v8.20~101
X-Git-Url: https://www.infradead.org/git/?a=commitdiff_plain;h=fd8cfdfd340a7daef61de50e4351128445136134;p=users%2Fdwmw2%2Fopenconnect.git

Check eventfd read/write returns

A short write should never happen but we get compiler/Coverity complaints
if we don't check.

Signed-off-by: David Woodhouse <dwmw2@infradead.org>
---

diff --git a/vhost.c b/vhost.c
index 94827675..6032bc2d 100644
--- a/vhost.c
+++ b/vhost.c
@@ -530,7 +530,11 @@ int vhost_tun_mainloop(struct openconnect_info *vpninfo, int *timeout, int reada
 
 	if (kick) {
 		barrier();
-		write(vpninfo->vhost_kick_fd, &kick, sizeof(kick));
+		if (write(vpninfo->vhost_kick_fd, &kick, sizeof(kick)) != sizeof(kick)) {
+			/* Can never happen */
+			vpn_progress(vpninfo, PRG_ERR,
+				     _("Failed to kick vhost-net eventfd\n"));
+		}
 		vpn_progress(vpninfo, PRG_TRACE,
 			     _("Kick vhost ring\n"));
 		did_work = 1;
@@ -542,7 +546,11 @@ int vhost_tun_mainloop(struct openconnect_info *vpninfo, int *timeout, int reada
 	 * again. */
 	if (!did_work && readable) {
 		uint64_t evt;
-		read(vpninfo->vhost_call_fd, &evt, sizeof(evt));
+		if (read(vpninfo->vhost_call_fd, &evt, sizeof(evt)) != sizeof(evt)) {
+			/* Can never happen */
+			vpn_progress(vpninfo, PRG_ERR,
+				     _("Failed to read vhost-net call eventfd\n"));
+		}
 	}
 
 	/* If we aren't going to have one more turn around the mainloop,