From: Junio C Hamano <gitster@pobox.com>
Date: Thu, 8 Mar 2018 20:36:26 +0000 (-0800)
Subject: Merge branch 'ds/find-unique-abbrev-optim'
X-Git-Tag: v2.17.0-rc0~26
X-Git-Url: https://git.lorimer.id.au/gitweb.git/diff_plain/7519a60ffa3f811ec49fd9956e284ff90f3b1cf1?hp=-c

Merge branch 'ds/find-unique-abbrev-optim'

While finding unique object name abbreviation, the code may
accidentally have read beyond the end of the array of object names
in a pack.

* ds/find-unique-abbrev-optim:
sha1_name: fix uninitialized memory errors
---

7519a60ffa3f811ec49fd9956e284ff90f3b1cf1
diff --combined sha1_name.c
index e7c18ffc26,f1c3d37a6d..735c1c0b8e
--- a/sha1_name.c
+++ b/sha1_name.c
@@@ -159,7 -159,7 +159,7 @@@ static void unique_in_pack(struct packe
  	num = p->num_objects;
  	last = num;
  	while (first < last) {
 -		uint32_t mid = (first + last) / 2;
 +		uint32_t mid = first + (last - first) / 2;
  		const unsigned char *current;
  		int cmp;
  
@@@ -381,7 -381,7 +381,7 @@@ static int show_ambiguous_object(const 
  
  	advise("  %s %s%s",
  	       find_unique_abbrev(oid->hash, DEFAULT_ABBREV),
 -	       typename(type) ? typename(type) : "unknown type",
 +	       type_name(type) ? type_name(type) : "unknown type",
  	       desc.buf);
  
  	strbuf_release(&desc);
@@@ -542,20 -542,20 +542,20 @@@ static void find_abbrev_len_for_pack(st
  	/*
  	 * first is now the position in the packfile where we would insert
  	 * mad->hash if it does not exist (or the position of mad->hash if
- 	 * it does exist). Hence, we consider a maximum of three objects
+ 	 * it does exist). Hence, we consider a maximum of two objects
  	 * nearby for the abbreviation length.
  	 */
  	mad->init_len = 0;
  	if (!match) {
- 		nth_packed_object_oid(&oid, p, first);
- 		extend_abbrev_len(&oid, mad);
+ 		if (nth_packed_object_oid(&oid, p, first))
+ 			extend_abbrev_len(&oid, mad);
  	} else if (first < num - 1) {
- 		nth_packed_object_oid(&oid, p, first + 1);
- 		extend_abbrev_len(&oid, mad);
+ 		if (nth_packed_object_oid(&oid, p, first + 1))
+ 			extend_abbrev_len(&oid, mad);
  	}
  	if (first > 0) {
- 		nth_packed_object_oid(&oid, p, first - 1);
- 		extend_abbrev_len(&oid, mad);
+ 		if (nth_packed_object_oid(&oid, p, first - 1))
+ 			extend_abbrev_len(&oid, mad);
  	}
  	mad->init_len = mad->cur_len;
  }
@@@ -706,7 -706,7 +706,7 @@@ static int get_oid_basic(const char *st
  
  	if (len == GIT_SHA1_HEXSZ && !get_oid_hex(str, oid)) {
  		if (warn_ambiguous_refs && warn_on_object_refname_ambiguity) {
 -			refs_found = dwim_ref(str, len, tmp_oid.hash, &real_ref);
 +			refs_found = dwim_ref(str, len, &tmp_oid, &real_ref);
  			if (refs_found > 0) {
  				warning(warn_msg, len, str);
  				if (advice_object_name_warning)
@@@ -757,11 -757,11 +757,11 @@@
  
  	if (!len && reflog_len)
  		/* allow "@{...}" to mean the current branch reflog */
 -		refs_found = dwim_ref("HEAD", 4, oid->hash, &real_ref);
 +		refs_found = dwim_ref("HEAD", 4, oid, &real_ref);
  	else if (reflog_len)
 -		refs_found = dwim_log(str, len, oid->hash, &real_ref);
 +		refs_found = dwim_log(str, len, oid, &real_ref);
  	else
 -		refs_found = dwim_ref(str, len, oid->hash, &real_ref);
 +		refs_found = dwim_ref(str, len, oid, &real_ref);
  
  	if (!refs_found)
  		return -1;
@@@ -800,7 -800,7 +800,7 @@@
  				return -1;
  			}
  		}
 -		if (read_ref_at(real_ref, flags, at_time, nth, oid->hash, NULL,
 +		if (read_ref_at(real_ref, flags, at_time, nth, oid, NULL,
  				&co_time, &co_tz, &co_cnt)) {
  			if (!len) {
  				if (starts_with(real_ref, "refs/heads/")) {
@@@ -901,8 -901,8 +901,8 @@@ struct object *peel_to_type(const char 
  			if (name)
  				error("%.*s: expected %s type, but the object "
  				      "dereferences to %s type",
 -				      namelen, name, typename(expected_type),
 -				      typename(o->type));
 +				      namelen, name, type_name(expected_type),
 +				      type_name(o->type));
  			return NULL;
  		}
  	}
@@@ -1434,23 -1434,10 +1434,23 @@@ void strbuf_branchname(struct strbuf *s
  
  int strbuf_check_branch_ref(struct strbuf *sb, const char *name)
  {
 -	strbuf_branchname(sb, name, INTERPRET_BRANCH_LOCAL);
 -	if (name[0] == '-')
 -		return -1;
 +	if (startup_info->have_repository)
 +		strbuf_branchname(sb, name, INTERPRET_BRANCH_LOCAL);
 +	else
 +		strbuf_addstr(sb, name);
 +
 +	/*
 +	 * This splice must be done even if we end up rejecting the
 +	 * name; builtin/branch.c::copy_or_rename_branch() still wants
 +	 * to see what the name expanded to so that "branch -m" can be
 +	 * used as a tool to correct earlier mistakes.
 +	 */
  	strbuf_splice(sb, 0, 0, "refs/heads/", 11);
 +
 +	if (*name == '-' ||
 +	    !strcmp(sb->buf, "refs/heads/HEAD"))
 +		return -1;
 +
  	return check_refname_format(sb->buf, 0);
  }