Re: strcpy -> strlcpy?
:It was primarily done in OpenBSD to avoid introducing new bugs. If I
:remember right, when we did the complete tree sweep, it caught around 10
:bugs or so in the conversions. More in ports after doing a bulk build.
:I wouldn't bother with it if you aren't planning to do a similar mass
:conversion to strlcpy-style functions.
:
:Note that the patch does other things as well; it detects incorrect use of
:static buffers if the buffer size specified is larger than the actual
:buffer. This has found around 60-70 bugs, mainly in the ports tree (a lot
:of them are sscanf string size specifiers which are off-by-one).
:
:Doing more complicated analyses is a pain in gcc though; I started hacking
:on some stuff using CIL by George Necula at Berkeley, which makes static
:analysis of real-world C much, much easier.
:
:--
:Anil Madhavapeddy http://anil.recoil.org
It sounds like a better approach to detecting these sorts of
bugs would be to have a separate code parser and analysis tool. C
is actually very easy to parse (having written a C compiler I can
say that with assurance), and even not all that hard to analyze.
The hard part is producing the assembly/other output. I'll bet it
would be easier then trying to build it directly into the GCC
framework.
-Matt
Matthew Dillon
<dillon@backplane.com>
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