[alsa-devel] [PATCH RESEND] ASoC: wm_adsp: Fix validation of firmware and coeff lengths
The checks for whether another region/block header could be present are subtracting the size from the current offset. Obviously we should instead subtract the offset from the size.
The checks for whether the region/block data fit in the file are adding the data size to the current offset and header size, without checking for integer overflow. Rearrange these so that overflow is impossible.
Cc: stable@vger.kernel.org Signed-off-by: Ben Hutchings ben.hutchings@codethink.co.uk Acked-by: Charles Keepax ckeepax@opensource.cirrus.com Tested-by: Charles Keepax ckeepax@opensource.cirrus.com --- sound/soc/codecs/wm_adsp.c | 12 ++++++------ 1 file changed, 6 insertions(+), 6 deletions(-)
diff --git a/sound/soc/codecs/wm_adsp.c b/sound/soc/codecs/wm_adsp.c index 65c059b5ffd7..66e32f5d2917 100644 --- a/sound/soc/codecs/wm_adsp.c +++ b/sound/soc/codecs/wm_adsp.c @@ -1733,7 +1733,7 @@ static int wm_adsp_load(struct wm_adsp *dsp) le64_to_cpu(footer->timestamp));
while (pos < firmware->size && - pos - firmware->size > sizeof(*region)) { + sizeof(*region) < firmware->size - pos) { region = (void *)&(firmware->data[pos]); region_name = "Unknown"; reg = 0; @@ -1782,8 +1782,8 @@ static int wm_adsp_load(struct wm_adsp *dsp) regions, le32_to_cpu(region->len), offset, region_name);
- if ((pos + le32_to_cpu(region->len) + sizeof(*region)) > - firmware->size) { + if (le32_to_cpu(region->len) > + firmware->size - pos - sizeof(*region)) { adsp_err(dsp, "%s.%d: %s region len %d bytes exceeds file length %zu\n", file, regions, region_name, @@ -2253,7 +2253,7 @@ static int wm_adsp_load_coeff(struct wm_adsp *dsp)
blocks = 0; while (pos < firmware->size && - pos - firmware->size > sizeof(*blk)) { + sizeof(*blk) < firmware->size - pos) { blk = (void *)(&firmware->data[pos]);
type = le16_to_cpu(blk->type); @@ -2327,8 +2327,8 @@ static int wm_adsp_load_coeff(struct wm_adsp *dsp) }
if (reg) { - if ((pos + le32_to_cpu(blk->len) + sizeof(*blk)) > - firmware->size) { + if (le32_to_cpu(blk->len) > + firmware->size - pos - sizeof(*blk)) { adsp_err(dsp, "%s.%d: %s region len %d bytes exceeds file length %zu\n", file, blocks, region_name,
On Fri, Dec 08, 2017 at 04:15:20PM +0000, Ben Hutchings wrote:
The checks for whether another region/block header could be present are subtracting the size from the current offset. Obviously we should instead subtract the offset from the size.
This is described as a resend but I checked and I've not been sent this patch before :(
participants (2)
-
Ben Hutchings
-
Mark Brown