Wireshark-dev: Re: [Wireshark-dev] DND crash through all versions?
From: Tony Trinh <tony19@xxxxxxxxx>
Date: Mon, 3 Sep 2012 18:36:56 -0400
On Mon, Sep 3, 2012 at 5:50 PM, Jaap Keuter <jaap.keuter@xxxxxxxxx> wrote:
Anyone knows what strstr() does with a NULL for a haystack? As far as I can tell it's unspecified.

I think you're right. "Undefined/unspecified behavior" usually means a segfault from my experience. This is true for strstr() in OSX ML.

strstr() apparently does not null-check its parameters in the latest versions of Linux [1], OSX/Darwin (and probably other Un*x) [2], and Windows [3]. I couldn't find the Windows source for strstr(), but MSDN indicates:

strstr and wcsstr do not validate their parameters.

Interestingly, Windows does have an error handler in _mbsstr() for invalid parameters.