Re: [PATCH u-boot-mvebu 4/5] tools: kwboot: Fix sending very small images

Stefan Roese
2023-03-24T08:23:49Z

On 3/23/23 20:57, Pali Rohár wrote:
> Sending of very small images (smaller than 128 bytes = xmodem block size)
> cause out-of-bound memory read access. Fix this issue by ensuring that
> hdrsz when sending image is not larger than total size of the image.
> Issue was introduced in commit f8017c37799c ("tools: kwboot: Fix sending
> Kirkwood v0 images"). Special case when total image is smaller than header
> size aligned to multiply of xmodem size is already handled since that
> commit.
>
> Fixes: f8017c37799c ("tools: kwboot: Fix sending Kirkwood v0 images")
> Signed-off-by: Pali Rohár <pali@kernel.org>

Reviewed-by: Stefan Roese <sr@denx.de>

Thanks,
Stefan

> ---
> tools/kwboot.c | 2 ++
> 1 file changed, 2 insertions(+)
>
> diff --git a/tools/kwboot.c b/tools/kwboot.c
> index 23a893a9b9f8..1cf78dda6755 100644
> --- a/tools/kwboot.c
> +++ b/tools/kwboot.c
> @@ -1458,6 +1458,8 @@ kwboot_xmodem(int tty, const void *_img, size_t size, int baudrate)
> * followed by the header. So align header size to xmodem block size.
> */
> hdrsz += (KWBOOT_XM_BLKSZ - hdrsz % KWBOOT_XM_BLKSZ) % KWBOOT_XM_BLKSZ;
> + if (hdrsz > size)
> + hdrsz = size;
>
> pnum = 1;
>

Viele Grüße,
Stefan Roese

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