Re: [PATCH] getgr_r: Reserve space for gr_mem's NULL terminator in buffer

[Rich Felker <dalias@aerifal.cx>]

By the way, how did you come across the bugs you're reporting? Are you
testing software against musl, or directly reviewing the source? I'm
just curious since you've already found a couple important issues that
our existing methodologies have so far missed, and I'm hoping we can
stamp out a lot more bugs like this between now and the 1.0 release.

Rich



On Sat, Sep 28, 2013 at 11:08:46PM -0700, Michael Forney wrote:
> Currently, the NULL terminator overlaps with the beginning of the line, causing
> gr_name to always be the empty string.
> ---
> As an aside, I don't understand why 32 is added to the size check. It looks
> like the length is rounded down to a multiple of 16, so at most 15 extra bytes
> will be needed. But even so, wouldn't it be better to check for exactly the
> amount of space that will be used? Or is it not worth the additional temporary
> variable?
> 
>  src/passwd/getgr_r.c | 4 ++--
>  1 file changed, 2 insertions(+), 2 deletions(-)