Re: [PATCH] Add overflow check to get_delta_hdr_size
Martin Koegler <martin.koegler@chello.at> writes:
Show 7 quoted lines
> From: Martin Koegler <martin.koegler@chello.at>
>
> Signed-off-by: Martin Koegler <martin.koegler@chello.at>
> ---
> Applies on top of my size_t series
>
> I'm not sure, if die or error is better.
As there is no fallback when we hit it, die would be sufficient; the only thing the callers of this helper, or their callers, could do is as a reaction to an error return from here would be to die themselves, I would think.
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>
> delta.h | 5 +++++
> 1 file changed, 5 insertions(+)
>
> diff --git a/delta.h b/delta.h
> index 2df0f55..18a4983 100644
> --- a/delta.h
> +++ b/delta.h
> @@ -96,6 +96,11 @@ static inline size_t get_delta_hdr_size(const unsigned char **datap,
> cmd = *data++;
> size |= (cmd & 0x7f) << i;
> i += 7;
> + if (bitsizeof(size_t) <= i) {
> + error("too large object size");
> + size = 0;
> + break;
> + }
> } while (cmd & 0x80 && data < top);
> *datap = data;
> return size;
Martin Koegler