Re: [PATCH v2] rev-parse: Check argc before using argv[i+1]
- From
Junio C Hamano <gitster@pobox.com>
- Date
- Jan 28, 2014, 21:43 UTC
- Message-ID
- <xmqqmwiflr37.fsf@gitster.dls.corp.google.com>
- In-Reply-To
- <1390944060-783-1-git-send-email-dhsharp@google.com>
David Sharp <dhsharp@google.com> writes:
> Without this patch, git-rev-parse --prefix, --default, or > --resolve-git-dir, without a value argument, would result in a segfault. > Instead, die() with a message.
When I sent the review message, I actually was on the fence between checking i vs argc and checking the nullness myself. I realize, after seeing the actual patch below, that we are protecting against picking up a NULL and blindly passing it on in the codepaths that follow, so the updated code does look a lot better, at least to me.
Thanks.
Show 47 quoted lines
>
> Signed-off-by: David Sharp <dhsharp@google.com>
> ---
> builtin/rev-parse.c | 17 +++++++++++------
> 1 file changed, 11 insertions(+), 6 deletions(-)
>
> diff --git a/builtin/rev-parse.c b/builtin/rev-parse.c
> index aaeb611..45901df 100644
> --- a/builtin/rev-parse.c
> +++ b/builtin/rev-parse.c
> @@ -547,15 +547,17 @@ int cmd_rev_parse(int argc, const char **argv, const char *prefix)
> continue;
> }
> if (!strcmp(arg, "--default")) {
> - def = argv[i+1];
> - i++;
> + def = argv[++i];
> + if (!def)
> + die("--default requires an argument");
> continue;
> }
> if (!strcmp(arg, "--prefix")) {
> - prefix = argv[i+1];
> + prefix = argv[++i];
> + if (!prefix)
> + die("--prefix requires an argument");
> startup_info->prefix = prefix;
> output_prefix = 1;
> - i++;
> continue;
> }
> if (!strcmp(arg, "--revs-only")) {
> @@ -738,9 +740,12 @@ int cmd_rev_parse(int argc, const char **argv, const char *prefix)
> continue;
> }
> if (!strcmp(arg, "--resolve-git-dir")) {
> - const char *gitdir = resolve_gitdir(argv[i+1]);
> + const char *gitdir = argv[++i];
> if (!gitdir)
> - die("not a gitdir '%s'", argv[i+1]);
> + die("--resolve-git-dir requires an argument");
> + gitdir = resolve_gitdir(gitdir);
> + if (!gitdir)
> + die("not a gitdir '%s'", argv[i]);
> puts(gitdir);
> continue;
> }