Re: [PATCH 1/9] stream_blob_to_fd: detect errors reading from stream

> We call read_istream, but never check its return value for
> errors. This can lead to us looping infinitely, as we just
> keep trying to write "-1" bytes (and we do not notice the
> error, as we simply check that write_in_full reports the
> same number of bytes we fed it, which of course is also -1).

>
> Signed-off-by: Jeff King <peff@peff.net>
> ---
> No test yet, as my method for triggering this causes _another_ infinite
> loop. So the test comes after the fixes, to avoid infinite loops when
> bisecting the history later. :)
>
>  streaming.c | 2 ++
>  1 file changed, 2 insertions(+)
>
> diff --git a/streaming.c b/streaming.c
> index 4d978e5..f4126a7 100644
> --- a/streaming.c
> +++ b/streaming.c
> @@ -514,6 +514,8 @@ int stream_blob_to_fd(int fd, unsigned const char *sha1, struct stream_filter *f
>  		ssize_t wrote, holeto;
>  		ssize_t readlen = read_istream(st, buf, sizeof(buf));
>  
> +		if (readlen < 0)
> +			goto close_and_exit;
>  		if (!readlen)
>  			break;
>  		if (can_seek && sizeof(buf) == readlen) {