Re: [PATCH] Add overflow check to get_delta_hdr_size
From: Junio C Hamano <hidden>
Date: 2017-08-14 16:56:06
Martin Koegler [off-list ref] writes:
From: Martin Koegler <redacted> Signed-off-by: Martin Koegler <redacted> --- 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.
quoted hunk
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;