Keys are int.  HMP sendkey assigns them from the value strtoul(),
silently truncating values greater than INT_MAX.  Fix to reject them.

While there, use qemu_strtoul() instead of strtoul() so checkpatch.pl
won't complain.

Signed-off-by: Markus Armbruster <armbru@redhat.com>
Reviewed-by: Daniel P. Berrangé <berrange@redhat.com>
---
 monitor/hmp-cmds.c | 9 +++++++--
 1 file changed, 7 insertions(+), 2 deletions(-)

diff --git a/monitor/hmp-cmds.c b/monitor/hmp-cmds.c
index 01b789a79e..a7c9ae2520 100644
--- a/monitor/hmp-cmds.c
+++ b/monitor/hmp-cmds.c
@@ -1666,8 +1666,13 @@ void hmp_sendkey(Monitor *mon, const QDict *qdict)
         v = g_malloc0(sizeof(*v));
 
         if (strstart(keys, "0x", NULL)) {
-            char *endp;
-            int value = strtoul(keys, &endp, 0);
+            const char *endp;
+            unsigned long value;
+
+            if (qemu_strtoul(keys, &endp, 0, &value) < 0
+                || value >= INT_MAX) {
+                goto err_out;
+            }
             assert(endp <= keys + keyname_len);
             if (endp != keys + keyname_len) {
                 goto err_out;
-- 
2.37.3