Re: [PATCH] builtin/mv: fix out of bounds write

> When commit a88c915 (mv: move submodules using a gitfile, 2013-07-30)
> added the submodule_gitfile array, it was not added to the block that
> enlarges the arrays when we are moving a directory so that we do not
> have to worry about it being a directory when we perform the actual
> move.  After this, the loop continues over the enlarged set of sources.
> 
> Since we assume that submodule_gitfile has size argc, if any of the
> items in the source directory are submodules we are guaranteed to write
> beyond the end of submodule_gitfile.
> 
> Fix this by realloc'ing submodule_gitfile at the same time as the other
> arrays.
> 
> Reported-by: Guillaume Gelin <contact@ramnes.eu>
> Signed-off-by: John Keeping <john@keeping.me.uk>
> ---
> On Sat, Mar 08, 2014 at 06:12:18PM +0000, John Keeping wrote:
> > This fixes it for me:
> 
> Here it is as a proper patch.
> 
>  builtin/mv.c | 3 +++
>  1 file changed, 3 insertions(+)
> 
> diff --git a/builtin/mv.c b/builtin/mv.c
> index 21c46d1..f99c91e 100644
> --- a/builtin/mv.c
> +++ b/builtin/mv.c
> @@ -179,6 +179,9 @@ int cmd_mv(int argc, const char **argv, const char *prefix)
>  						modes = xrealloc(modes,
>  								(argc + last - first)
>  								* sizeof(enum update_mode));
> +						submodule_gitfile = xrealloc(submodule_gitfile,
> +								(argc + last - first)
> +								* sizeof(char *));
>  					}
>  
>  					dst = add_slash(dst);