index can be controlled by user-space, hence leading to a potential exploitation of the Spectre variant 1 vulnerability.
Smatch warning: drivers/media/platform/omap/omap_vout.c:1062 vidioc_enum_fmt_vid_out() warn: potential spectre issue 'omap_formats' Fix this by sanitizing index before using it to index omap_formats. Notice that given that speculation windows are large, the policy is to kill the speculation on the first load and not worry if it can be completed with a dependent load/store [1]. [1] https://marc.info/?l=linux-kernel&m=152449131114778&w=2 Cc: sta...@vger.kernel.org Reported-by: Dan Carpenter <dan.carpen...@oracle.com> Signed-off-by: Gustavo A. R. Silva <gust...@embeddedor.com> --- drivers/media/platform/omap/omap_vout.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/drivers/media/platform/omap/omap_vout.c b/drivers/media/platform/omap/omap_vout.c index 5700b78..1a7ec39 100644 --- a/drivers/media/platform/omap/omap_vout.c +++ b/drivers/media/platform/omap/omap_vout.c @@ -51,6 +51,8 @@ #include "omap_voutdef.h" #include "omap_vout_vrfb.h" +#include <linux/nospec.h> + MODULE_AUTHOR("Texas Instruments"); MODULE_DESCRIPTION("OMAP Video for Linux Video out driver"); MODULE_LICENSE("GPL"); @@ -1059,6 +1061,7 @@ static int vidioc_enum_fmt_vid_out(struct file *file, void *fh, if (index >= NUM_OUTPUT_FORMATS) return -EINVAL; + index = array_index_nospec(index, NUM_OUTPUT_FORMATS); fmt->flags = omap_formats[index].flags; strlcpy(fmt->description, omap_formats[index].description, sizeof(fmt->description)); -- 2.7.4
