Re: [PATCH v3 1/3] dir: change the scope of function 'directory_exists_in_index()'
- From
Johannes Schindelin <johannes.schindelin@gmx.de>
- Date
- Dec 19, 2020, 00:08 UTC
- Message-ID
- <nycvar.QRO.7.76.6.2012190104140.56@tvgsbejvaqbjf.bet>
- In-Reply-To
- <20201214231939.644175-2-periperidip@gmail.com>
Hi Shourya,
On Tue, 15 Dec 2020, Shourya Shukla wrote:
Show 7 quoted lines
> Change the scope of the function 'directory_exists_in_index()' as well > as declare it in 'dir.h'. > > Since the return type of the function is the enumerator 'exist_status', > change its scope as well and declare it in 'dir.h'. While at it, rename > the members of the aforementioned enum so as to avoid any naming clashes > or confusions later on.
This makes it sound as if only existing code was adjusted, in a minimal way, but no new code was introduced. But that's not true:
Show 9 quoted lines
> > Helped-by: Christian Couder <christian.couder@gmail.com> > Helped-by: Kaartic Sivaraam <kaartic.sivaraam@gmail.com> > Signed-off-by: Shourya Shukla <periperidip@gmail.com> > --- > builtin/submodule--helper.c | 408 ++++++++++++++++++++++++++++++++++++ > dir.c | 30 ++- > dir.h | 9 + > 3 files changed, 429 insertions(+), 18 deletions(-)
Tons of new code there. And unfortunately...
Show 110 quoted lines
>
> diff --git a/builtin/submodule--helper.c b/builtin/submodule--helper.c
> index c30896c897..4dfad35d77 100644
> --- a/builtin/submodule--helper.c
> +++ b/builtin/submodule--helper.c
> @@ -2744,6 +2744,414 @@ static int module_set_branch(int argc, const char **argv, const char *prefix)
> return !!ret;
> }
>
> +struct add_data {
> + const char *prefix;
> + const char *branch;
> + const char *reference_path;
> + const char *sm_path;
> + const char *sm_name;
> + const char *repo;
> + const char *realrepo;
> + int depth;
> + unsigned int force: 1;
> + unsigned int quiet: 1;
> + unsigned int progress: 1;
> + unsigned int dissociate: 1;
> +};
> +#define ADD_DATA_INIT { 0 }
> +
> +/*
> + * Guess the directory name from the repository URL by performing the
> + * operations below in the following order:
> + *
> + * - If the URL ends with '/', remove that.
> + *
> + * - If the result of the above ends with zero or more ':', followed
> + * by zero or more '/', followed by ".git", drop the matching part.
> + *
> + * - If the result of the above has '/' or ':' in it, remove everything
> + * before it and '/' or ':' itself.
> + */
> +static char *guess_dir_name(const char *repo)
> +{
> + const char *start, *end;
> +
> + start = repo;
> + end = repo + strlen(repo);
> +
> + /* remove the trailing '/' */
> + if (repo < end - 1 && end[-1] == '/')
> + end--;
> +
> + /* remove the trailing ':', '/' and '.git' */
> + if (repo < end - 4 && !memcmp(".git", end - 4, 4)) {
> + end -= 4;
> + while (repo < end - 1 && end[-1] == '/')
> + end--;
> + while (repo < end - 1 && end[-1] == ':')
> + end--;
> + }
> +
> + /* find the last ':' or '/' */
> + for (start = end - 1; repo <= start; start--) {
> + if (*start == '/' || *start == ':')
> + break;
> + }
> + /* exclude '/' or ':' itself */
> + start++;
> +
> + return xmemdupz(start, end - start);
> +}
> +
> +static int can_create_submodule(unsigned int force, const char *path)
> +{
> + int cache_pos, dir_in_cache = 0;
> +
> + if (read_cache() < 0)
> + die(_("index file corrupt"));
> +
> + cache_pos = cache_name_pos(path, strlen(path));
> + if(cache_pos < 0 &&
> + directory_exists_in_index(&the_index, path, strlen(path)) == is_cache_directory)
> + dir_in_cache = 1;
> +
> + if (!force) {
> + if (cache_pos >= 0 || dir_in_cache)
> + die(_("'%s' already exists in the index"), path);
> + } else {
> + struct cache_entry *ce = NULL;
> + if (cache_pos >= 0)
> + ce = the_index.cache[cache_pos];
> + if (dir_in_cache || (ce && !S_ISGITLINK(ce->ce_mode)))
> + die(_("'%s' already exists in the index and is not a "
> + "submodule"), path);
> + }
> + return 0;
> +}
> +
> +static const char *parse_token(const char *cp, int *len)
> +{
> + const char *p = cp, *start, *end;
> + char *str;
> +
> + start = p;
> + while (*p != ' ')
> + p++;
> + end = p;
> + str = xstrndup(start, end - start);
> +
> + while(*p == ' ')
> + p++;
> +
> + return str;
> +}This function is not careful enough to avoid buffer overruns. It even triggers a segmentation fault in our test suite: https://github.com/gitgitgadget/git/runs/1574891976?check_suite_focus=true#step:6:3152
I need this to make it pass (only tested locally so far, but I trust you to take the baton from here):
-- snipsnap -- From c28c0cd3ac21d546394335957fbaa350ab287c3f Mon Sep 17 00:00:00 2001 From: Johannes Schindelin <johannes.schindelin@gmx.de> Date: Sat, 19 Dec 2020 01:02:04 +0100 Subject: [PATCH] fixup??? dir: change the scope of function 'directory_exists_in_index()'
This fixes the segmentation fault reported in the linux-musl job of our CI builds. Valgrind has this to say about it:
==32354== ==32354== Process terminating with default action of signal 11 (SIGSEGV) ==32354== Access not within mapped region at address 0x5C73000 ==32354== at 0x202F5A: parse_token (submodule--helper.c:2837) ==32354== by 0x20319B: report_fetch_remotes (submodule--helper.c:2871) ==32354== by 0x2033FD: add_submodule (submodule--helper.c:2898) ==32354== by 0x204612: module_add (submodule--helper.c:3146) ==32354== by 0x20478A: cmd_submodule__helper (submodule--helper.c:3202) ==32354== by 0x12655E: run_builtin (git.c:458) ==32354== by 0x1269B4: handle_builtin (git.c:712) ==32354== by 0x126C79: run_argv (git.c:779) ==32354== by 0x12715C: cmd_main (git.c:913) ==32354== by 0x2149A2: main (common-main.c:52)
Signed-off-by: Johannes Schindelin <johannes.schindelin@gmx.de> --- builtin/submodule--helper.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/builtin/submodule--helper.c b/builtin/submodule--helper.c index 4f1d892b9a9..29a6f80b937 100644 --- a/builtin/submodule--helper.c +++ b/builtin/submodule--helper.c @@ -2834,12 +2834,12 @@ static const char *parse_token(const char *cp, int *len) char *str; start = p; - while (*p != ' ') + while (*p && *p != ' ') p++; end = p; str = xstrndup(start, end - start); - while(*p == ' ') + while(*p && *p == ' ') p++; return str; -- 2.29.2.windows.1.1.g3464b98ce68