git/builtin/reset.c
Andrzej Hunt e901de6816 reset: free instead of leaking unneeded ref
dwim_ref() allocs a new string into ref. Instead of setting to NULL to
discard it, we can FREE_AND_NULL.

This leak appears to have been introduced in:
4cf76f6bbf (builtin/reset: compute checkout metadata for reset, 2020-03-16)

This leak was found when running t0001 with LSAN, see also LSAN output below:

Direct leak of 5 byte(s) in 1 object(s) allocated from:
    #0 0x486514 in strdup /home/abuild/rpmbuild/BUILD/llvm-11.0.0.src/build/../projects/compiler-rt/lib/asan/asan_interceptors.cpp:452:3
    #1 0x9a7108 in xstrdup /home/ahunt/oss-fuzz/git/wrapper.c:29:14
    #2 0x8add6b in expand_ref /home/ahunt/oss-fuzz/git/refs.c:670:12
    #3 0x8ad777 in repo_dwim_ref /home/ahunt/oss-fuzz/git/refs.c:644:22
    #4 0x6394af in dwim_ref /home/ahunt/oss-fuzz/git/./refs.h:162:9
    #5 0x637e5c in cmd_reset /home/ahunt/oss-fuzz/git/builtin/reset.c:426:4
    #6 0x4cd60d in run_builtin /home/ahunt/oss-fuzz/git/git.c:453:11
    #7 0x4cb2da in handle_builtin /home/ahunt/oss-fuzz/git/git.c:704:3
    #8 0x4ccc37 in run_argv /home/ahunt/oss-fuzz/git/git.c:771:4
    #9 0x4cac29 in cmd_main /home/ahunt/oss-fuzz/git/git.c:902:19
    #10 0x69c5ce in main /home/ahunt/oss-fuzz/git/common-main.c:52:11
    #11 0x7f57ebb9d349 in __libc_start_main (/lib64/libc.so.6+0x24349)

Signed-off-by: Andrzej Hunt <ajrhunt@google.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
2021-03-14 15:57:59 -07:00

455 lines
13 KiB
C

/*
* "git reset" builtin command
*
* Copyright (c) 2007 Carlos Rica
*
* Based on git-reset.sh, which is
*
* Copyright (c) 2005, 2006 Linus Torvalds and Junio C Hamano
*/
#define USE_THE_INDEX_COMPATIBILITY_MACROS
#include "builtin.h"
#include "config.h"
#include "lockfile.h"
#include "tag.h"
#include "object.h"
#include "pretty.h"
#include "run-command.h"
#include "refs.h"
#include "diff.h"
#include "diffcore.h"
#include "tree.h"
#include "branch.h"
#include "parse-options.h"
#include "unpack-trees.h"
#include "cache-tree.h"
#include "submodule.h"
#include "submodule-config.h"
#define REFRESH_INDEX_DELAY_WARNING_IN_MS (2 * 1000)
static const char * const git_reset_usage[] = {
N_("git reset [--mixed | --soft | --hard | --merge | --keep] [-q] [<commit>]"),
N_("git reset [-q] [<tree-ish>] [--] <pathspec>..."),
N_("git reset [-q] [--pathspec-from-file [--pathspec-file-nul]] [<tree-ish>]"),
N_("git reset --patch [<tree-ish>] [--] [<pathspec>...]"),
NULL
};
enum reset_type { MIXED, SOFT, HARD, MERGE, KEEP, NONE };
static const char *reset_type_names[] = {
N_("mixed"), N_("soft"), N_("hard"), N_("merge"), N_("keep"), NULL
};
static inline int is_merge(void)
{
return !access(git_path_merge_head(the_repository), F_OK);
}
static int reset_index(const char *ref, const struct object_id *oid, int reset_type, int quiet)
{
int i, nr = 0;
struct tree_desc desc[2];
struct tree *tree;
struct unpack_trees_options opts;
int ret = -1;
memset(&opts, 0, sizeof(opts));
opts.head_idx = 1;
opts.src_index = &the_index;
opts.dst_index = &the_index;
opts.fn = oneway_merge;
opts.merge = 1;
init_checkout_metadata(&opts.meta, ref, oid, NULL);
if (!quiet)
opts.verbose_update = 1;
switch (reset_type) {
case KEEP:
case MERGE:
opts.update = 1;
break;
case HARD:
opts.update = 1;
/* fallthrough */
default:
opts.reset = 1;
}
read_cache_unmerged();
if (reset_type == KEEP) {
struct object_id head_oid;
if (get_oid("HEAD", &head_oid))
return error(_("You do not have a valid HEAD."));
if (!fill_tree_descriptor(the_repository, desc + nr, &head_oid))
return error(_("Failed to find tree of HEAD."));
nr++;
opts.fn = twoway_merge;
}
if (!fill_tree_descriptor(the_repository, desc + nr, oid)) {
error(_("Failed to find tree of %s."), oid_to_hex(oid));
goto out;
}
nr++;
if (unpack_trees(nr, desc, &opts))
goto out;
if (reset_type == MIXED || reset_type == HARD) {
tree = parse_tree_indirect(oid);
prime_cache_tree(the_repository, the_repository->index, tree);
}
ret = 0;
out:
for (i = 0; i < nr; i++)
free((void *)desc[i].buffer);
return ret;
}
static void print_new_head_line(struct commit *commit)
{
struct strbuf buf = STRBUF_INIT;
printf(_("HEAD is now at %s"),
find_unique_abbrev(&commit->object.oid, DEFAULT_ABBREV));
pp_commit_easy(CMIT_FMT_ONELINE, commit, &buf);
if (buf.len > 0)
printf(" %s", buf.buf);
putchar('\n');
strbuf_release(&buf);
}
static void update_index_from_diff(struct diff_queue_struct *q,
struct diff_options *opt, void *data)
{
int i;
int intent_to_add = *(int *)data;
for (i = 0; i < q->nr; i++) {
struct diff_filespec *one = q->queue[i]->one;
int is_missing = !(one->mode && !is_null_oid(&one->oid));
struct cache_entry *ce;
if (is_missing && !intent_to_add) {
remove_file_from_cache(one->path);
continue;
}
ce = make_cache_entry(&the_index, one->mode, &one->oid, one->path,
0, 0);
if (!ce)
die(_("make_cache_entry failed for path '%s'"),
one->path);
if (is_missing) {
ce->ce_flags |= CE_INTENT_TO_ADD;
set_object_name_for_intent_to_add_entry(ce);
}
add_cache_entry(ce, ADD_CACHE_OK_TO_ADD | ADD_CACHE_OK_TO_REPLACE);
}
}
static int read_from_tree(const struct pathspec *pathspec,
struct object_id *tree_oid,
int intent_to_add)
{
struct diff_options opt;
memset(&opt, 0, sizeof(opt));
copy_pathspec(&opt.pathspec, pathspec);
opt.output_format = DIFF_FORMAT_CALLBACK;
opt.format_callback = update_index_from_diff;
opt.format_callback_data = &intent_to_add;
opt.flags.override_submodule_config = 1;
opt.repo = the_repository;
if (do_diff_cache(tree_oid, &opt))
return 1;
diffcore_std(&opt);
diff_flush(&opt);
clear_pathspec(&opt.pathspec);
return 0;
}
static void set_reflog_message(struct strbuf *sb, const char *action,
const char *rev)
{
const char *rla = getenv("GIT_REFLOG_ACTION");
strbuf_reset(sb);
if (rla)
strbuf_addf(sb, "%s: %s", rla, action);
else if (rev)
strbuf_addf(sb, "reset: moving to %s", rev);
else
strbuf_addf(sb, "reset: %s", action);
}
static void die_if_unmerged_cache(int reset_type)
{
if (is_merge() || unmerged_cache())
die(_("Cannot do a %s reset in the middle of a merge."),
_(reset_type_names[reset_type]));
}
static void parse_args(struct pathspec *pathspec,
const char **argv, const char *prefix,
int patch_mode,
const char **rev_ret)
{
const char *rev = "HEAD";
struct object_id unused;
/*
* Possible arguments are:
*
* git reset [-opts] [<rev>]
* git reset [-opts] <tree> [<paths>...]
* git reset [-opts] <tree> -- [<paths>...]
* git reset [-opts] -- [<paths>...]
* git reset [-opts] <paths>...
*
* At this point, argv points immediately after [-opts].
*/
if (argv[0]) {
if (!strcmp(argv[0], "--")) {
argv++; /* reset to HEAD, possibly with paths */
} else if (argv[1] && !strcmp(argv[1], "--")) {
rev = argv[0];
argv += 2;
}
/*
* Otherwise, argv[0] could be either <rev> or <paths> and
* has to be unambiguous. If there is a single argument, it
* can not be a tree
*/
else if ((!argv[1] && !get_oid_committish(argv[0], &unused)) ||
(argv[1] && !get_oid_treeish(argv[0], &unused))) {
/*
* Ok, argv[0] looks like a commit/tree; it should not
* be a filename.
*/
verify_non_filename(prefix, argv[0]);
rev = *argv++;
} else {
/* Otherwise we treat this as a filename */
verify_filename(prefix, argv[0], 1);
}
}
*rev_ret = rev;
if (read_cache() < 0)
die(_("index file corrupt"));
parse_pathspec(pathspec, 0,
PATHSPEC_PREFER_FULL |
(patch_mode ? PATHSPEC_PREFIX_ORIGIN : 0),
prefix, argv);
}
static int reset_refs(const char *rev, const struct object_id *oid)
{
int update_ref_status;
struct strbuf msg = STRBUF_INIT;
struct object_id *orig = NULL, oid_orig,
*old_orig = NULL, oid_old_orig;
if (!get_oid("ORIG_HEAD", &oid_old_orig))
old_orig = &oid_old_orig;
if (!get_oid("HEAD", &oid_orig)) {
orig = &oid_orig;
set_reflog_message(&msg, "updating ORIG_HEAD", NULL);
update_ref(msg.buf, "ORIG_HEAD", orig, old_orig, 0,
UPDATE_REFS_MSG_ON_ERR);
} else if (old_orig)
delete_ref(NULL, "ORIG_HEAD", old_orig, 0);
set_reflog_message(&msg, "updating HEAD", rev);
update_ref_status = update_ref(msg.buf, "HEAD", oid, orig, 0,
UPDATE_REFS_MSG_ON_ERR);
strbuf_release(&msg);
return update_ref_status;
}
static int git_reset_config(const char *var, const char *value, void *cb)
{
if (!strcmp(var, "submodule.recurse"))
return git_default_submodule_config(var, value, cb);
return git_default_config(var, value, cb);
}
int cmd_reset(int argc, const char **argv, const char *prefix)
{
int reset_type = NONE, update_ref_status = 0, quiet = 0;
int patch_mode = 0, pathspec_file_nul = 0, unborn;
const char *rev, *pathspec_from_file = NULL;
struct object_id oid;
struct pathspec pathspec;
int intent_to_add = 0;
const struct option options[] = {
OPT__QUIET(&quiet, N_("be quiet, only report errors")),
OPT_SET_INT(0, "mixed", &reset_type,
N_("reset HEAD and index"), MIXED),
OPT_SET_INT(0, "soft", &reset_type, N_("reset only HEAD"), SOFT),
OPT_SET_INT(0, "hard", &reset_type,
N_("reset HEAD, index and working tree"), HARD),
OPT_SET_INT(0, "merge", &reset_type,
N_("reset HEAD, index and working tree"), MERGE),
OPT_SET_INT(0, "keep", &reset_type,
N_("reset HEAD but keep local changes"), KEEP),
OPT_CALLBACK_F(0, "recurse-submodules", NULL,
"reset", "control recursive updating of submodules",
PARSE_OPT_OPTARG, option_parse_recurse_submodules_worktree_updater),
OPT_BOOL('p', "patch", &patch_mode, N_("select hunks interactively")),
OPT_BOOL('N', "intent-to-add", &intent_to_add,
N_("record only the fact that removed paths will be added later")),
OPT_PATHSPEC_FROM_FILE(&pathspec_from_file),
OPT_PATHSPEC_FILE_NUL(&pathspec_file_nul),
OPT_END()
};
git_config(git_reset_config, NULL);
git_config_get_bool("reset.quiet", &quiet);
argc = parse_options(argc, argv, prefix, options, git_reset_usage,
PARSE_OPT_KEEP_DASHDASH);
parse_args(&pathspec, argv, prefix, patch_mode, &rev);
if (pathspec_from_file) {
if (patch_mode)
die(_("--pathspec-from-file is incompatible with --patch"));
if (pathspec.nr)
die(_("--pathspec-from-file is incompatible with pathspec arguments"));
parse_pathspec_file(&pathspec, 0,
PATHSPEC_PREFER_FULL,
prefix, pathspec_from_file, pathspec_file_nul);
} else if (pathspec_file_nul) {
die(_("--pathspec-file-nul requires --pathspec-from-file"));
}
unborn = !strcmp(rev, "HEAD") && get_oid("HEAD", &oid);
if (unborn) {
/* reset on unborn branch: treat as reset to empty tree */
oidcpy(&oid, the_hash_algo->empty_tree);
} else if (!pathspec.nr && !patch_mode) {
struct commit *commit;
if (get_oid_committish(rev, &oid))
die(_("Failed to resolve '%s' as a valid revision."), rev);
commit = lookup_commit_reference(the_repository, &oid);
if (!commit)
die(_("Could not parse object '%s'."), rev);
oidcpy(&oid, &commit->object.oid);
} else {
struct tree *tree;
if (get_oid_treeish(rev, &oid))
die(_("Failed to resolve '%s' as a valid tree."), rev);
tree = parse_tree_indirect(&oid);
if (!tree)
die(_("Could not parse object '%s'."), rev);
oidcpy(&oid, &tree->object.oid);
}
if (patch_mode) {
if (reset_type != NONE)
die(_("--patch is incompatible with --{hard,mixed,soft}"));
trace2_cmd_mode("patch-interactive");
return run_add_interactive(rev, "--patch=reset", &pathspec);
}
/* git reset tree [--] paths... can be used to
* load chosen paths from the tree into the index without
* affecting the working tree nor HEAD. */
if (pathspec.nr) {
if (reset_type == MIXED)
warning(_("--mixed with paths is deprecated; use 'git reset -- <paths>' instead."));
else if (reset_type != NONE)
die(_("Cannot do %s reset with paths."),
_(reset_type_names[reset_type]));
}
if (reset_type == NONE)
reset_type = MIXED; /* by default */
if (pathspec.nr)
trace2_cmd_mode("path");
else
trace2_cmd_mode(reset_type_names[reset_type]);
if (reset_type != SOFT && (reset_type != MIXED || get_git_work_tree()))
setup_work_tree();
if (reset_type == MIXED && is_bare_repository())
die(_("%s reset is not allowed in a bare repository"),
_(reset_type_names[reset_type]));
if (intent_to_add && reset_type != MIXED)
die(_("-N can only be used with --mixed"));
/* Soft reset does not touch the index file nor the working tree
* at all, but requires them in a good order. Other resets reset
* the index file to the tree object we are switching to. */
if (reset_type == SOFT || reset_type == KEEP)
die_if_unmerged_cache(reset_type);
if (reset_type != SOFT) {
struct lock_file lock = LOCK_INIT;
hold_locked_index(&lock, LOCK_DIE_ON_ERROR);
if (reset_type == MIXED) {
int flags = quiet ? REFRESH_QUIET : REFRESH_IN_PORCELAIN;
if (read_from_tree(&pathspec, &oid, intent_to_add))
return 1;
the_index.updated_skipworktree = 1;
if (!quiet && get_git_work_tree()) {
uint64_t t_begin, t_delta_in_ms;
t_begin = getnanotime();
refresh_index(&the_index, flags, NULL, NULL,
_("Unstaged changes after reset:"));
t_delta_in_ms = (getnanotime() - t_begin) / 1000000;
if (advice_reset_quiet_warning && t_delta_in_ms > REFRESH_INDEX_DELAY_WARNING_IN_MS) {
printf(_("\nIt took %.2f seconds to enumerate unstaged changes after reset. You can\n"
"use '--quiet' to avoid this. Set the config setting reset.quiet to true\n"
"to make this the default.\n"), t_delta_in_ms / 1000.0);
}
}
} else {
struct object_id dummy;
char *ref = NULL;
int err;
dwim_ref(rev, strlen(rev), &dummy, &ref, 0);
if (ref && !starts_with(ref, "refs/"))
FREE_AND_NULL(ref);
err = reset_index(ref, &oid, reset_type, quiet);
if (reset_type == KEEP && !err)
err = reset_index(ref, &oid, MIXED, quiet);
if (err)
die(_("Could not reset index file to revision '%s'."), rev);
free(ref);
}
if (write_locked_index(&the_index, &lock, COMMIT_LOCK))
die(_("Could not write new index file."));
}
if (!pathspec.nr && !unborn) {
/* Any resets without paths update HEAD to the head being
* switched to, saving the previous head in ORIG_HEAD before. */
update_ref_status = reset_refs(rev, &oid);
if (reset_type == HARD && !update_ref_status && !quiet)
print_new_head_line(lookup_commit_reference(the_repository, &oid));
}
if (!pathspec.nr)
remove_branch_state(the_repository, 0);
return update_ref_status;
}