[Qemu-devel] [PULL 2/2] ide: avoid referencing NULL dev in rotational rate setting

[John Snow <jsnow@redhat.com>]

From: "Daniel P. Berrange" <berrange@redhat.com>

The 'dev' variable can be NULL when the guest OS calls identify on an IDE
unit that does not have a drive attached to it.

Signed-off-by: Daniel P. Berrange <berrange@redhat.com>
Reviewed-by: Stefan Hajnoczi <stefanha@redhat.com>
Message-id: 20171020091403.1479-1-berrange@redhat.com
Signed-off-by: John Snow <jsnow@redhat.com>
---
 hw/ide/core.c | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/hw/ide/core.c b/hw/ide/core.c
index a04766a..471d0c9 100644
--- a/hw/ide/core.c
+++ b/hw/ide/core.c
@@ -208,7 +208,9 @@ static void ide_identify(IDEState *s)
     if (dev && dev->conf.discard_granularity) {
         put_le16(p + 169, 1); /* TRIM support */
     }
-    put_le16(p + 217, dev->rotation_rate); /* Nominal media rotation rate */
+    if (dev) {
+        put_le16(p + 217, dev->rotation_rate); /* Nominal media rotation rate */
+    }
 
     ide_identify_size(s);
     s->identify_set = 1;
-- 
2.9.5