Commit 718f24ad9aaeb14a026216aca86035f7b5d58803
2019-10-30T20:39:03
commit: verify objects exist in git_commit_with_signature There can be a significant difference between the system where we created the buffer (if at all) and when the caller provides us with the contents of a commit. Verify that the commit we are being asked to create references objects which do exist in the target repository.
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diff --git a/src/commit.c b/src/commit.c
index 20e0b8a..aca65ff 100644
--- a/src/commit.c
+++ b/src/commit.c
@@ -878,6 +878,14 @@ static void format_header_field(git_buf *out, const char *field, const char *con
git_buf_putc(out, '\n');
}
+static const git_oid *commit_parent_from_commit(size_t n, void *payload)
+{
+ const git_commit *commit = (const git_commit *) payload;
+
+ return git_array_get(commit->parent_ids, n);
+
+}
+
int git_commit_create_with_signature(
git_oid *out,
git_repository *repo,
@@ -890,12 +898,26 @@ int git_commit_create_with_signature(
const char *field;
const char *header_end;
git_buf commit = GIT_BUF_INIT;
+ git_commit *parsed;
+ git_array_oid_t parents = GIT_ARRAY_INIT;
- /* We start by identifying the end of the commit header */
+ /* The first step is to verify that all the tree and parents exist */
+ parsed = git__calloc(1, sizeof(git_commit));
+ GIT_ERROR_CHECK_ALLOC(parsed);
+ if ((error = commit_parse(parsed, commit_content, strlen(commit_content), 0)) < 0)
+ goto cleanup;
+
+ if ((error = validate_tree_and_parents(&parents, repo, &parsed->tree_id, commit_parent_from_commit, parsed, NULL, true)) < 0)
+ goto cleanup;
+
+ git_array_clear(parents);
+
+ /* Then we start appending by identifying the end of the commit header */
header_end = strstr(commit_content, "\n\n");
if (!header_end) {
git_error_set(GIT_ERROR_INVALID, "malformed commit contents");
- return -1;
+ error = -1;
+ goto cleanup;
}
/* The header ends after the first LF */
@@ -919,6 +941,7 @@ int git_commit_create_with_signature(
goto cleanup;
cleanup:
+ git_commit__free(parsed);
git_buf_dispose(&commit);
return error;
}