Add image format option for USB mass-storage devices
(fix CVE-2008-1945)
Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
git-svn-id: svn://svn.savannah.nongnu.org/qemu/trunk@5059 c046a42c-6fe2-441c-8c8c-71466251a162
diff --git a/hw/usb-msd.c b/hw/usb-msd.c
index 01d492d..f7ad25e 100644
--- a/hw/usb-msd.c
+++ b/hw/usb-msd.c
@@ -517,13 +517,42 @@
{
MSDState *s;
BlockDriverState *bdrv;
+ BlockDriver *drv = NULL;
+ const char *p1;
+ char fmt[32];
+
+ p1 = strchr(filename, ':');
+ if (p1++) {
+ const char *p2;
+
+ if (strstart(filename, "format=", &p2)) {
+ int len = MIN(p1 - p2, sizeof(fmt));
+ pstrcpy(fmt, len, p2);
+
+ drv = bdrv_find_format(fmt);
+ if (!drv) {
+ printf("invalid format %s\n", fmt);
+ return NULL;
+ }
+ } else if (*filename != ':') {
+ printf("unrecognized USB mass-storage option %s\n", filename);
+ return NULL;
+ }
+
+ filename = p1;
+ }
+
+ if (!*filename) {
+ printf("block device specification needed\n");
+ return NULL;
+ }
s = qemu_mallocz(sizeof(MSDState));
if (!s)
return NULL;
bdrv = bdrv_new("usb");
- if (bdrv_open(bdrv, filename, 0) < 0)
+ if (bdrv_open2(bdrv, filename, 0, drv) < 0)
goto fail;
if (qemu_key_check(bdrv, filename))
goto fail;
diff --git a/qemu-doc.texi b/qemu-doc.texi
index 636d819..9519d9a 100644
--- a/qemu-doc.texi
+++ b/qemu-doc.texi
@@ -550,8 +550,10 @@
means qemu is able to report the mouse position without having to grab the
mouse. Also overrides the PS/2 mouse emulation when activated.
-@item disk:file
-Mass storage device based on file
+@item disk:[format=@var{format}]:file
+Mass storage device based on file. The optional @var{format} argument
+will be used rather than detecting the format. Can be used to specifiy
+format=raw to avoid interpreting an untrusted format header.
@item host:bus.addr
Pass through the host device identified by bus.addr (Linux only).
