[GSoC][PATCH 2/2] refs: add name and content check for file backend
- From
shejialuo <shejialuo@gmail.com>
- Date
- May 30, 2024, 12:27 UTC
- Message-ID
- <20240530122753.1114818-3-shejialuo@gmail.com>
- In-Reply-To
- <20240530122753.1114818-1-shejialuo@gmail.com>
The existing git-fsck does not fully check bad format ref name such as standalone '@' or name ending with ".lock". And also `git-fsck` does not fully check ref content, the following contents will not be reported by the original git-fsck command.
1. "c71dba5654404b9b0d378a6cbff1b743b9d31a34 garbage": with trailing characters. 2. "c71dba5654404b9b0d378a6cbff1b743b9d31a34 ": with trailing empty characters. 3. "C71DBA5654404b9b0d378a6cbff1b743b9d31A34": with uppercase hex. 4. "z71dba5654404b9b0d378a6cbff1b743b9d31a34": with not hex character.
Provide functionality to support such consistency checks for branch and tag refs and add a new unit test to verify this functionality.
Mentored-by: Patrick Steinhardt <ps@pks.im> Mentored-by: Karthik Nayak <karthik.188@gmail.com> Signed-off-by: shejialuo <shejialuo@gmail.com> --- refs/files-backend.c | 112 ++++++++++++++++++++++++++++++++- t/t0602-reffiles-fsck.sh | 132 +++++++++++++++++++++++++++++++++++++++ 2 files changed, 243 insertions(+), 1 deletion(-) create mode 100755 t/t0602-reffiles-fsck.sh
diff --git a/refs/files-backend.c b/refs/files-backend.c index b6147c588b..3c811f5c03 100644 --- a/refs/files-backend.c +++ b/refs/files-backend.c @@ -3299,11 +3299,121 @@ static int files_init_db(struct ref_store *ref_store, return 0; } -static int files_fsck(struct ref_store *ref_store) +typedef int (*files_fsck_refs_fn)(const char *refs_check_dir, + struct dir_iterator *iter); + +static int files_fsck_refs_name(const char *refs_check_dir, + struct dir_iterator *iter) { + if (check_refname_format(iter->basename, REFNAME_ALLOW_ONELEVEL)) { + error(_("%s/%s: invalid refname format"), refs_check_dir, iter->basename); + return -1; + } + return 0; } +static int files_fsck_refs_content(const char *refs_check_dir, + struct dir_iterator *iter) +{ + struct strbuf ref_content = STRBUF_INIT; + + if (strbuf_read_file(&ref_content, iter->path.buf, 0) < 0) { + error(_("%s/%s: unable to read the ref"), refs_check_dir, iter->basename); + goto clean; + } + + /* + * Case 1: check if the ref content length is valid and the last + * character is a newline. + */ + if (ref_content.len != the_hash_algo->hexsz + 1 || + ref_content.buf[ref_content.len - 1] != '\n') { + goto failure; + } + + /* + * Case 2: the content should be range of [0-9a-f]. + */ + for (size_t i = 0; i < the_hash_algo->hexsz; i++) { + if (!isdigit(ref_content.buf[i]) && + (ref_content.buf[i] < 'a' || ref_content.buf[i] > 'f')) { + goto failure; + } + } + + strbuf_release(&ref_content); + return 0; + +failure: + error(_("%s/%s: invalid ref content"), refs_check_dir, iter->basename); + +clean: + strbuf_release(&ref_content); + return -1; +} + +static int files_fsck_refs(struct ref_store *ref_store, + const char* refs_check_dir, + files_fsck_refs_fn *fsck_refs_fns) +{ + struct dir_iterator *iter; + struct strbuf sb = STRBUF_INIT; + int ret = 0; + int iter_status; + + strbuf_addf(&sb, "%s/%s", ref_store->gitdir, refs_check_dir); + + iter = dir_iterator_begin(sb.buf, 0); + + /* + * The current implementation does not care about the worktree, the worktree + * may have no refs/heads or refs/tags directory. Simply return 0 now. + */ + if (!iter) { + return 0; + } + + while ((iter_status = dir_iterator_advance(iter)) == ITER_OK) { + if (S_ISDIR(iter->st.st_mode)) { + continue; + } else if (S_ISREG(iter->st.st_mode)) { + for (files_fsck_refs_fn *fsck_refs_fn = fsck_refs_fns; + *fsck_refs_fn; fsck_refs_fn++) { + ret |= (*fsck_refs_fn)(refs_check_dir, iter); + } + } else { + error(_("unexpected file type for '%s'"), iter->basename); + ret = -1; + } + } + + if (iter_status != ITER_DONE) { + ret = -1; + error(_("failed to iterate over '%s'"), sb.buf); + } + + strbuf_release(&sb); + + return ret; +} + +static int files_fsck(struct ref_store *ref_store) +{ + int ret = 0; + + files_fsck_refs_fn fsck_refs_fns[] = { + files_fsck_refs_name, + files_fsck_refs_content, + NULL + }; + + ret = files_fsck_refs(ref_store, "refs/heads",fsck_refs_fns) + | files_fsck_refs(ref_store, "refs/tags", fsck_refs_fns); + + return ret; +} + struct ref_storage_be refs_be_files = { .name = "files", .init = files_ref_store_create, diff --git a/t/t0602-reffiles-fsck.sh b/t/t0602-reffiles-fsck.sh new file mode 100755 index 0000000000..1c6c3804ff --- /dev/null +++ b/t/t0602-reffiles-fsck.sh @@ -0,0 +1,132 @@ +#!/bin/bash + +test_description='Test reffiles backend consistency check' + +GIT_TEST_DEFAULT_INITIAL_BRANCH_NAME=main +export GIT_TEST_DEFAULT_INITIAL_BRANCH_NAME +GIT_TEST_DEFAULT_REF_FORMAT=files +export GIT_TEST_DEFAULT_REF_FORMAT + +. ./test-lib.sh + +test_expect_success 'ref name should be checked' ' + test_when_finished "rm -rf repo" && + git init repo && + branch_dir_prefix=.git/refs/heads && + tag_dir_prefix=.git/refs/tags && + ( + cd repo && + git commit --allow-empty -m initial && + git checkout -b branch-1 && + git tag tag-1 && + git commit --allow-empty -m second && + git checkout -b branch-2 && + git tag tag-2 + ) && + ( + cd repo && + cp $branch_dir_prefix/branch-1 $branch_dir_prefix/.branch-1 && + test_must_fail git fsck 2>err && + cat >expect <<-EOF && + error: refs/heads/.branch-1: invalid refname format + error: ref database is corrupt + EOF + rm $branch_dir_prefix/.branch-1 && + test_cmp expect err + ) && + ( + cd repo && + cp $tag_dir_prefix/tag-1 $tag_dir_prefix/tag-1.lock && + test_must_fail git fsck 2>err && + cat >expect <<-EOF && + error: refs/tags/tag-1.lock: invalid refname format + error: ref database is corrupt + EOF + rm $tag_dir_prefix/tag-1.lock && + test_cmp expect err + ) && + ( + cd repo && + cp $branch_dir_prefix/branch-1 $branch_dir_prefix/@ && + test_must_fail git fsck 2>err && + cat >expect <<-EOF && + error: refs/heads/@: invalid refname format + error: ref database is corrupt + EOF + rm $branch_dir_prefix/@ && + test_cmp expect err + ) +' + +test_expect_success 'ref content should be checked' ' + test_when_finished "rm -rf repo" && + git init repo && + branch_dir_prefix=.git/refs/heads && + tag_dir_prefix=.git/refs/tags && + ( + cd repo && + git commit --allow-empty -m initial && + git checkout -b branch-1 && + git tag tag-1 && + git commit --allow-empty -m second && + git checkout -b branch-2 && + git tag tag-2 + ) && + ( + cd repo && + printf "%s garbage" "$(git rev-parse branch-1)" > $branch_dir_prefix/branch-1-garbage && + test_must_fail git fsck 2>err && + cat >expect <<-EOF && + error: refs/heads/branch-1-garbage: invalid ref content + error: ref database is corrupt + EOF + rm $branch_dir_prefix/branch-1-garbage && + test_cmp expect err + ) && + ( + cd repo && + printf "%s garbage" "$(git rev-parse tag-1)" > $tag_dir_prefix/tag-1-garbage && + test_must_fail git fsck 2>err && + cat >expect <<-EOF && + error: refs/tags/tag-1-garbage: invalid ref content + error: ref database is corrupt + EOF + rm $tag_dir_prefix/tag-1-garbage && + test_cmp expect err + ) && + ( + cd repo && + printf "%s " "$(git rev-parse tag-2)" > $tag_dir_prefix/tag-2-garbage && + test_must_fail git fsck 2>err && + cat >expect <<-EOF && + error: refs/tags/tag-2-garbage: invalid ref content + error: ref database is corrupt + EOF + rm $tag_dir_prefix/tag-2-garbage && + test_cmp expect err + ) && + ( + cd repo && + tr -d "\n" < $branch_dir_prefix/branch-1 > $branch_dir_prefix/branch-1-without-newline && + test_must_fail git fsck 2>err && + cat >expect <<-EOF && + error: refs/heads/branch-1-without-newline: invalid ref content + error: ref database is corrupt + EOF + rm $branch_dir_prefix/branch-1-without-newline && + test_cmp expect err + ) && + ( + cd repo && + tr "[:lower:]" "[:upper:]" < $branch_dir_prefix/branch-2 > $branch_dir_prefix/branch-2-upper && + test_must_fail git fsck 2>err && + cat >expect <<-EOF && + error: refs/heads/branch-2-upper: invalid ref content + error: ref database is corrupt + EOF + rm $branch_dir_prefix/branch-2-upper && + test_cmp expect err + ) +' + +test_done
-- 2.45.1