In 4ac9006f832 (real_path: have callers use real_pathdup and strbuf_realpath, 2016-12-12), we changed the xstrdup(real_path()) pattern to use real_pathdup() directly. The only problem with this change is that real_path() calls strbuf_realpath() with die_on_error = 1 while real_pathdup() calls it with die_on_error = 0. Meaning that in cases where real_path() causes Git to die() with an error message, real_pathdup() is silent and returns NULL instead. The callers, however, are ill-prepared for that change, as they expect the return value to be non-NULL. This patch fixes that by extending real_pathdup()'s signature to accept the die_on_error flag and simply pass it through to strbuf_realpath(), and then adjust all callers after a careful audit whether they would handle NULLs well. Note: this fix not only prevents NULL pointer accesses, but it also reintroduces the error messages that were lost with the change to real_pathdup(). Signed-off-by: Johannes Schindelin <johannes.schindelin@xxxxxx> --- abspath.c | 4 ++-- builtin/init-db.c | 6 +++--- cache.h | 2 +- dir.c | 4 ++-- environment.c | 2 +- setup.c | 4 ++-- submodule.c | 10 +++++----- t/t1501-work-tree.sh | 2 +- worktree.c | 2 +- 9 files changed, 18 insertions(+), 18 deletions(-) diff --git a/abspath.c b/abspath.c index 2f0c26e0e2c..b02e068aa34 100644 --- a/abspath.c +++ b/abspath.c @@ -214,12 +214,12 @@ const char *real_path_if_valid(const char *path) return strbuf_realpath(&realpath, path, 0); } -char *real_pathdup(const char *path) +char *real_pathdup(const char *path, int die_on_error) { struct strbuf realpath = STRBUF_INIT; char *retval = NULL; - if (strbuf_realpath(&realpath, path, 0)) + if (strbuf_realpath(&realpath, path, die_on_error)) retval = strbuf_detach(&realpath, NULL); strbuf_release(&realpath); diff --git a/builtin/init-db.c b/builtin/init-db.c index 1d4d6a00789..8a6acb0ec69 100644 --- a/builtin/init-db.c +++ b/builtin/init-db.c @@ -338,7 +338,7 @@ int init_db(const char *git_dir, const char *real_git_dir, { int reinit; int exist_ok = flags & INIT_DB_EXIST_OK; - char *original_git_dir = real_pathdup(git_dir); + char *original_git_dir = real_pathdup(git_dir, 1); if (real_git_dir) { struct stat st; @@ -489,7 +489,7 @@ int cmd_init_db(int argc, const char **argv, const char *prefix) argc = parse_options(argc, argv, prefix, init_db_options, init_db_usage, 0); if (real_git_dir && !is_absolute_path(real_git_dir)) - real_git_dir = real_pathdup(real_git_dir); + real_git_dir = real_pathdup(real_git_dir, 1); if (argc == 1) { int mkdir_tried = 0; @@ -560,7 +560,7 @@ int cmd_init_db(int argc, const char **argv, const char *prefix) const char *git_dir_parent = strrchr(git_dir, '/'); if (git_dir_parent) { char *rel = xstrndup(git_dir, git_dir_parent - git_dir); - git_work_tree_cfg = real_pathdup(rel); + git_work_tree_cfg = real_pathdup(rel, 1); free(rel); } if (!git_work_tree_cfg) diff --git a/cache.h b/cache.h index 80b6372cf76..ae0b4fc70b5 100644 --- a/cache.h +++ b/cache.h @@ -1153,7 +1153,7 @@ char *strbuf_realpath(struct strbuf *resolved, const char *path, int die_on_error); const char *real_path(const char *path); const char *real_path_if_valid(const char *path); -char *real_pathdup(const char *path); +char *real_pathdup(const char *path, int die_on_error); const char *absolute_path(const char *path); char *absolute_pathdup(const char *path); const char *remove_leading_path(const char *in, const char *prefix); diff --git a/dir.c b/dir.c index 4541f9e1460..aeeb5ce1049 100644 --- a/dir.c +++ b/dir.c @@ -2730,8 +2730,8 @@ void connect_work_tree_and_git_dir(const char *work_tree_, const char *git_dir_) { struct strbuf file_name = STRBUF_INIT; struct strbuf rel_path = STRBUF_INIT; - char *git_dir = real_pathdup(git_dir_); - char *work_tree = real_pathdup(work_tree_); + char *git_dir = real_pathdup(git_dir_, 1); + char *work_tree = real_pathdup(work_tree_, 1); /* Update gitfile */ strbuf_addf(&file_name, "%s/.git", work_tree); diff --git a/environment.c b/environment.c index c07fb17fb70..42dc3106d2f 100644 --- a/environment.c +++ b/environment.c @@ -259,7 +259,7 @@ void set_git_work_tree(const char *new_work_tree) return; } git_work_tree_initialized = 1; - work_tree = real_pathdup(new_work_tree); + work_tree = real_pathdup(new_work_tree, 1); } const char *get_git_work_tree(void) diff --git a/setup.c b/setup.c index 967f289f1ef..6b48cb91ff2 100644 --- a/setup.c +++ b/setup.c @@ -698,7 +698,7 @@ static const char *setup_discovered_git_dir(const char *gitdir, /* --work-tree is set without --git-dir; use discovered one */ if (getenv(GIT_WORK_TREE_ENVIRONMENT) || git_work_tree_cfg) { if (offset != cwd->len && !is_absolute_path(gitdir)) - gitdir = real_pathdup(gitdir); + gitdir = real_pathdup(gitdir, 1); if (chdir(cwd->buf)) die_errno("Could not come back to cwd"); return setup_explicit_git_dir(gitdir, cwd, nongit_ok); @@ -806,7 +806,7 @@ static int canonicalize_ceiling_entry(struct string_list_item *item, /* Keep entry but do not canonicalize it */ return 1; } else { - char *real_path = real_pathdup(ceil); + char *real_path = real_pathdup(ceil, 0); if (!real_path) { return 0; } diff --git a/submodule.c b/submodule.c index 3b98766a6bc..0a2831d846d 100644 --- a/submodule.c +++ b/submodule.c @@ -1403,7 +1403,7 @@ static void relocate_single_git_dir_into_superproject(const char *prefix, /* If it is an actual gitfile, it doesn't need migration. */ return; - real_old_git_dir = real_pathdup(old_git_dir); + real_old_git_dir = real_pathdup(old_git_dir, 1); sub = submodule_from_path(null_sha1, path); if (!sub) @@ -1412,7 +1412,7 @@ static void relocate_single_git_dir_into_superproject(const char *prefix, new_git_dir = git_path("modules/%s", sub->name); if (safe_create_leading_directories_const(new_git_dir) < 0) die(_("could not create directory '%s'"), new_git_dir); - real_new_git_dir = real_pathdup(new_git_dir); + real_new_git_dir = real_pathdup(new_git_dir, 1); if (!prefix) prefix = get_super_prefix(); @@ -1472,14 +1472,14 @@ void absorb_git_dir_into_superproject(const char *prefix, new_git_dir = git_path("modules/%s", sub->name); if (safe_create_leading_directories_const(new_git_dir) < 0) die(_("could not create directory '%s'"), new_git_dir); - real_new_git_dir = real_pathdup(new_git_dir); + real_new_git_dir = real_pathdup(new_git_dir, 1); connect_work_tree_and_git_dir(path, real_new_git_dir); free(real_new_git_dir); } else { /* Is it already absorbed into the superprojects git dir? */ - char *real_sub_git_dir = real_pathdup(sub_git_dir); - char *real_common_git_dir = real_pathdup(get_git_common_dir()); + char *real_sub_git_dir = real_pathdup(sub_git_dir, 1); + char *real_common_git_dir = real_pathdup(get_git_common_dir(), 1); if (!starts_with(real_sub_git_dir, real_common_git_dir)) relocate_single_git_dir_into_superproject(prefix, path); diff --git a/t/t1501-work-tree.sh b/t/t1501-work-tree.sh index 046d9b7909f..b06210ec5e8 100755 --- a/t/t1501-work-tree.sh +++ b/t/t1501-work-tree.sh @@ -423,7 +423,7 @@ test_expect_success '$GIT_WORK_TREE overrides $GIT_DIR/common' ' ) ' -test_expect_failure 'error out gracefully on invalid $GIT_WORK_TREE' ' +test_expect_success 'error out gracefully on invalid $GIT_WORK_TREE' ' ( GIT_WORK_TREE=/.invalid/work/tree && export GIT_WORK_TREE && diff --git a/worktree.c b/worktree.c index d633761575b..0486e31ad4a 100644 --- a/worktree.c +++ b/worktree.c @@ -255,7 +255,7 @@ struct worktree *find_worktree(struct worktree **list, return wt; arg = prefix_filename(prefix, strlen(prefix), arg); - path = real_pathdup(arg); + path = real_pathdup(arg, 1); for (; *list; list++) if (!fspathcmp(path, real_path((*list)->path))) break; -- 2.12.0.windows.1.7.g94dafc3b124