From: Alex Riesen <raa.lkml@gmail.com>
Date: Thu, 06 Apr 2006 14:11:22 GMT
Subject: Re: unchecked uses of strdup
Message-ID: <81b0412b0604060711o57fb110cm5fa559c0fd785a66@mail.gmail.com>
In-Reply-To: <87d5fwau3z.fsf_-_@rho.meyering.net>

On 4/5/06, Jim Meyering <jim@meyering.net> wrote:
> There are pretty many uses of strdup in git's sources.
> Here's one that can cause trouble if it ever returns NULL:
>
>     [from fsck-objects.c]
>     static int fsck_head_link(void)
>     {
>             unsigned char sha1[20];
>             const char *git_HEAD = strdup(git_path("HEAD"));
>             const char *git_refs_heads_master = resolve_ref(git_HEAD, sha1, 1);
>
> The problem is that resolve_ref does an unconditional `stat'
> on the parameter corresponding to the maybe-NULL git_HEAD.

That's actually alright (aside a nice core file). Worse are the cases
where a NULL would cause some "normal" behaviour, e.g. arguments,
which have a meaning for NULL value.