From: Randall S. Becker <rsbecker@nexbridge.com>
Date: Thu, 11 Jan 2018 13:40:01 GMT
Subject: RE: [PATCH] Replaced read with xread in transport-helper.c to fix SSIZE_MAX overun in t5509
Message-ID: <002101d38ae1$b1bacb40$153061c0$@nexbridge.com>
In-Reply-To: <20180111062048.GA31213@sigill.intra.peff.net>

On January 11, 2018 1:21 AM , Jeff King wrote:
> On Thu, Jan 11, 2018 at 12:40:05AM -0500, Randall S. Becker wrote:
> > This fix was needed on HPE NonStop NSE where SSIZE_MAX is less than
> > BUFFERSIZE resulting in EINVAL. The call to read in transport-helper.c
> > was the only place outside of wrapper.c.
> 
> For my own curiosity, what is SSIZE_MAX on your platform? BUFFERSIZE is
> only 64k. Do you really have 16-bit size_t?
> 
> I wondered if you would also need to set MAX_IO_SIZE, but it looks like we
> default it to SSIZE_MAX.

size_t is 32 or 64 depending on the memory model of how a program is compiled. SSIZE_MAX in limits.h is 53284, which is a message system limit. There was a previous fix associated with this size limit came from our team (commit a983e6ac58094a3b2466ad3be13049ce213f9fc3).

Cheers,
Randall