Attachment 304107 Details for Bug 444583 – Proposed patch for kvm from Chris Wright

[patch] Proposed patch for kvm from Chris Wright

kvm-qemu-block-format-arg.diff (text/plain), 2.94 KB, created by Tomas Hoger on 2008-04-29 11:33:44 UTC

(hide)

Description:

Filename:

MIME Type:

Creator: Tomas Hoger

Created: 2008-04-29 11:33:44 UTC

Size: 2.94 KB

patch

obsolete

>From: Chris Wright <chrisw@redhat.com>
>Subject: [PATCH] add format= to drive options
>
>A guest with a raw format disk can write any format header to that device.
>A subsequent restart of the guest will cause qemu to interpret the format
>header and could allow the guest read access to any host file.  Add a
>format= drive option to allow host to specify, e.g. format=raw, to give
>qemu a hint to choose a specific block format driver.  Originially noted
>by Avi Kivity <avi@qumranet.com>.
>
>Signed-off-by: Chris Wright <chrisw@redhat.com>
>---
> qemu/qemu-doc.texi |    4 ++++
> qemu/vl.c          |   13 +++++++++++--
> 2 files changed, 15 insertions(+), 2 deletions(-)
>
>diff --git a/qemu/qemu-doc.texi b/qemu/qemu-doc.texi
>index b9ab492..783d977 100644
>--- a/qemu/qemu-doc.texi
>+++ b/qemu/qemu-doc.texi
>@@ -260,6 +260,10 @@ These options have the same definition as they have in @option{-hdachs}.
> @var{snapshot} is "on" or "off" and allows to enable snapshot for given drive (see @option{-snapshot}).
> @item cache=@var{cache}
> @var{cache} is "on" or "off" and allows to disable host cache to access data.
>+@item format=@var{format}
>+Specify which disk @var{format} will be used rather than detecting
>+the format.  Can be used to specifiy format=raw to avoid interpreting
>+an untrusted format header.
> @end table
> 
> Instead of @option{-cdrom} you can use:
>diff --git a/qemu/vl.c b/qemu/vl.c
>index b425ab5..10181e8 100644
>--- a/qemu/vl.c
>+++ b/qemu/vl.c
>@@ -5079,6 +5079,7 @@ int drive_init(struct drive_opt *arg, int snapshot,
>     int bus_id, unit_id;
>     int cyls, heads, secs, translation;
>     BlockDriverState *bdrv;
>+    BlockDriver *drv = NULL;
>     int max_devs;
>     int index;
>     int cache;
>@@ -5087,7 +5088,7 @@ int drive_init(struct drive_opt *arg, int snapshot,
>     char *str = arg->opt;
>     char *params[] = { "bus", "unit", "if", "index", "cyls", "heads",
>                        "secs", "trans", "media", "snapshot", "file",
>-                       "cache", "boot", NULL };
>+                       "cache", "boot", "format", NULL };
> 
>     if (check_params(buf, sizeof(buf), params, str) < 0) {
>          fprintf(stderr, "qemu: unknown parameter '%s' in '%s'\n",
>@@ -5271,6 +5272,14 @@ int drive_init(struct drive_opt *arg, int snapshot,
> 	}
>     }
> 
>+    if (get_param_value(buf, sizeof(buf), "format", str)) {
>+	drv = bdrv_find_format(buf);
>+	if (!drv) {
>+	    fprintf(stderr, "qemu: '%s' invalid format\n", buf);
>+	    return -1;
>+	}
>+    }
>+
>     if (arg->file == NULL)
>         get_param_value(file, sizeof(file), "file", str);
>     else
>@@ -5376,7 +5385,7 @@ int drive_init(struct drive_opt *arg, int snapshot,
>         bdrv_flags |= BDRV_O_SNAPSHOT;
>     if (!cache)
>         bdrv_flags |= BDRV_O_DIRECT;
>-    if (bdrv_open(bdrv, file, bdrv_flags) < 0 || qemu_key_check(bdrv, file)) {
>+    if (bdrv_open2(bdrv, file, bdrv_flags, drv) < 0 || qemu_key_check(bdrv, file)) {
>         fprintf(stderr, "qemu: could not open disk image %s\n",
>                         file);
>         return -1;

Actions: View | Diff

Attachments on bug 444583: 304107 | 304108