scsi-disk: fix buffer overflow

In case s->version is shorter than 4 bytes we overflow the memcpy src
buffer.  Fix it by clearing the target buffer, then copy only the
amount of bytes we actually have.

Signed-off-by: Gerd Hoffmann <kraxel@redhat.com>
Signed-off-by: Anthony Liguori <aliguori@us.ibm.com>
(cherry picked from 314b1811c15f4e982e4667d9b845aee4b5a63d91)

Signed-off-by: Kevin Wolf <kwolf@redhat.com>

diff --git a/hw/scsi-disk.c b/hw/scsi-disk.c
index b34fbaa6746d66cce1526e88d67dadd9ed20712d..a79201213f35013c9d10055ca966b837a3825f4b 100644 (file)
--- a/hw/scsi-disk.c
+++ b/hw/scsi-disk.c
@@ -434,7 +434,9 @@ static int scsi_disk_emulate_inquiry(SCSIRequest *req, uint8_t *outbuf)
         memcpy(&outbuf[16], "QEMU HARDDISK   ", 16);
     }
     memcpy(&outbuf[8], "QEMU    ", 8);
-    memcpy(&outbuf[32], s->version ? s->version : QEMU_VERSION, 4);
+    memset(&outbuf[32], 0, 4);
+    memcpy(&outbuf[32], s->version ? s->version : QEMU_VERSION,
+           MIN(4, strlen(s->version ? s->version : QEMU_VERSION)));
     /* Identify device as SCSI-3 rev 1.
        Some later commands are also implemented. */
     outbuf[2] = 3;