From: Thomas Rast <trast@inf.ethz.ch>
Date: Fri, 16 Aug 2013 07:50:50 GMT
Subject: Re: [PATCH] Git segmentation faults if submodule path is empty.
Message-ID: <87zjsif50l.fsf@linux-k42r.v.cablecom.net>
In-Reply-To: <277BEB82-D618-48D9-A276-4B0E76A11A38@eyesopen.com>

Jharrod LaFon <jlafon@eyesopen.com> writes:

> Git fails due to a segmentation fault if a submodule path is empty.
> Here is an example .gitmodules that will cause a segmentation fault:
> [submodule "foo-module"]
>     path
>     url = http://host/repo.git
> $ git status
> Segmentation fault (core dumped)

Can you turn this into a test to guard against the bug reappearing?

> This occurs because in the function parse_submodule_config_option, the
> variable 'value' is assumed not to be null, and when passed as an
> argument to xstrdup a segmentation fault occurs if it is indeed null.
> This is the case when using the .gitmodules example above.
>
> This patch addresses the issue by returning from the function if
> 'value' is null before the call to xstrdup is made.
>
> Signed-off-by: Jharrod LaFon <jlafon <at> eyesopen.com>
> ---
>  submodule.c |    2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/submodule.c b/submodule.c
> index 1821a5b..880f21b 100644
> --- a/submodule.c
> +++ b/submodule.c
> @@ -130,7 +130,7 @@ int parse_submodule_config_option(const char *var, const char *value)
>  	const char *name, *key;
>  	int namelen;
>  
> -	if (parse_config_key(var, "submodule", &name, &namelen, &key) < 0 || !name)
> +	if (parse_config_key(var, "submodule", &name, &namelen, &key) < 0 || !name || !value)
>  		return 0;
>  
>  	if (!strcmp(key, "path")) {

-- 
Thomas Rast
trast@{inf,student}.ethz.ch