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| author | Haogang Chen <haogangchen@gmail.com> | 2011-11-29 18:32:25 -0300 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@suse.de> | 2012-01-25 17:24:50 -0800 |
| commit | 087bc746ef05511c3e416846a8eae4588756462c (patch) | |
| tree | c0d1c48dbc486fcf77c5c1910eff701ef58cdb32 /drivers/media | |
| parent | 9d3f99878bf33d36739bd772c7dafcb1f71387fb (diff) | |
| download | lwn-087bc746ef05511c3e416846a8eae4588756462c.tar.gz lwn-087bc746ef05511c3e416846a8eae4588756462c.zip | |
uvcvideo: Fix integer overflow in uvc_ioctl_ctrl_map()
commit 806e23e95f94a27ee445022d724060b9b45cb64a upstream.
There is a potential integer overflow in uvc_ioctl_ctrl_map(). When a
large xmap->menu_count is passed from the userspace, the subsequent call
to kmalloc() will allocate a buffer smaller than expected.
map->menu_count and map->menu_info would later be used in a loop (e.g.
in uvc_query_v4l2_ctrl), which leads to out-of-bound access.
The patch checks the ioctl argument and returns -EINVAL for zero or too
large values in xmap->menu_count.
Signed-off-by: Haogang Chen <haogangchen@gmail.com>
[laurent.pinchart@ideasonboard.com Prevent excessive memory consumption]
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
Diffstat (limited to 'drivers/media')
| -rw-r--r-- | drivers/media/video/uvc/uvc_v4l2.c | 9 | ||||
| -rw-r--r-- | drivers/media/video/uvc/uvcvideo.h | 1 |
2 files changed, 10 insertions, 0 deletions
diff --git a/drivers/media/video/uvc/uvc_v4l2.c b/drivers/media/video/uvc/uvc_v4l2.c index 543a80395b7f..dbefdb09c108 100644 --- a/drivers/media/video/uvc/uvc_v4l2.c +++ b/drivers/media/video/uvc/uvc_v4l2.c @@ -65,6 +65,15 @@ static int uvc_ioctl_ctrl_map(struct uvc_video_chain *chain, goto done; } + /* Prevent excessive memory consumption, as well as integer + * overflows. + */ + if (xmap->menu_count == 0 || + xmap->menu_count > UVC_MAX_CONTROL_MENU_ENTRIES) { + ret = -EINVAL; + goto done; + } + size = xmap->menu_count * sizeof(*map->menu_info); map->menu_info = kmalloc(size, GFP_KERNEL); if (map->menu_info == NULL) { diff --git a/drivers/media/video/uvc/uvcvideo.h b/drivers/media/video/uvc/uvcvideo.h index 2a38d5e55358..cf2401a041ae 100644 --- a/drivers/media/video/uvc/uvcvideo.h +++ b/drivers/media/video/uvc/uvcvideo.h @@ -200,6 +200,7 @@ struct uvc_xu_control { /* Maximum allowed number of control mappings per device */ #define UVC_MAX_CONTROL_MAPPINGS 1024 +#define UVC_MAX_CONTROL_MENU_ENTRIES 32 /* Devices quirks */ #define UVC_QUIRK_STATUS_INTERVAL 0x00000001 |