[Qemu-devel] [PATCH 2/2] hmp: fix bad value conversion for M type

[Luiz Capitulino]

The M type converts from megabytes to bytes. However, the value can be
negative before the conversion, which will lead to a flawed conversion.

For example, this:

 (qemu) balloon -1000000000000011
 (qemu)

Just "works", but the value passed by the balloon command will be
something else.

This patch fixes this problem by requering a positive value before
converting. There's really no reason to accept a negative value for
the M type.

Signed-off-by: Luiz Capitulino <address@hidden>
---
 monitor.c |    4 ++++
 1 file changed, 4 insertions(+)

diff --git a/monitor.c b/monitor.c
index 6178f48..2ea1536 100644
--- a/monitor.c
+++ b/monitor.c
@@ -3624,6 +3624,10 @@ static const mon_cmd_t *monitor_parse_command(Monitor 
*mon,
                     monitor_printf(mon, "integer is for 32-bit values\n");
                     goto fail;
                 } else if (c == 'M') {
+                    if (val < 0) {
+                        monitor_printf(mon, "enter a positive value\n");
+                        goto fail;
+                    }
                     val <<= 20;
                 }
                 qdict_put(qdict, key, qint_from_int(val));
-- 
1.7.9.2.384.g4a92a