rebase: guard non-branch symref targets
A local branch symbolic ref may point outside refs/heads/. Such an alias cannot be skipped like a branch-to-branch alias because its concrete target ref is absent from the local branch decoration list. However, queuing each alias independently can update the same target ref more than once and make the second compare-and-swap fail. A reservation from another worktree can also name either an alias or its resolved target ref, so checking only one form can miss an in-progress update. Fix these cases by checking both the literal alias and its resolved target ref against checked-out reservations. Deduplicate updates by target ref. Also reserve both forms when loading another worktree's update-refs state. This makes different aliases honor the same in-progress update. This keeps non-branch symrefs supported without allowing duplicate or cross-worktree ref updates. Signed-off-by: Son Luong Ngoc <sluongng@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
Son Luong Ngoc committed
Jul 22, 2026 at 08:15 UTC
056eed4ba7c60dfbb220e2ecc49313c919a22221
3 files changed
+106
branch.c
+15
@@ -442,10 +442,25 @@ static void prepare_checked_out_branches(void)
442
&update_refs)) {
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struct string_list_item *item;
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for_each_string_list_item(item, &update_refs) {
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+ char *resolved_ref;
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+ int flags = 0;
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+
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old = strmap_put(¤t_checked_out_branches,
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item->string,
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xstrdup(wt->path));
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free(old);
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+
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+ resolved_ref = refs_resolve_refdup(
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+ get_main_ref_store(the_repository),
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+ item->string, RESOLVE_REF_READING,
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+ NULL, &flags);
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+ if (resolved_ref && (flags & REF_ISSYMREF)) {
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+ old = strmap_put(
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+ ¤t_checked_out_branches,
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+ resolved_ref, xstrdup(wt->path));
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+ free(old);
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+ }
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+ free(resolved_ref);
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}
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string_list_clear(&update_refs, 1);
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}
sequencer.c
+19
@@ -6439,6 +6439,7 @@ struct todo_add_branch_context {
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size_t items_alloc;
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struct strbuf *buf;
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struct string_list refs_to_oids;
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+ struct string_list symref_update_targets;
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};
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static int add_decorations_to_list(const struct commit *commit,
@@ -6453,6 +6454,7 @@ static int add_decorations_to_list(const struct commit *commit,
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while (decoration) {
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struct todo_item *item;
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const char *path;
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+ const char *checked_ref;
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char *resolved_ref;
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int flags = 0;
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size_t base_offset = ctx->buf->len;
@@ -6488,6 +6490,17 @@ static int add_decorations_to_list(const struct commit *commit,
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}
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path = branch_checked_out(decoration->name);
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+ if (!path && resolved_ref && (flags & REF_ISSYMREF)) {
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+ checked_ref = resolved_ref;
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+ path = branch_checked_out(checked_ref);
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+ }
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+ if (!path && resolved_ref && (flags & REF_ISSYMREF) &&
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+ string_list_has_string(&ctx->symref_update_targets,
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+ resolved_ref)) {
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+ free(resolved_ref);
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+ decoration = decoration->next;
6502
+ continue;
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+ }
6504
6505
ALLOC_GROW(ctx->items,
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ctx->items_nr + 1,
@@ -6503,6 +6516,10 @@ static int add_decorations_to_list(const struct commit *commit,
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decoration->name, path);
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} else {
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struct string_list_item *sti;
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+
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+ if (resolved_ref && (flags & REF_ISSYMREF))
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+ string_list_insert(&ctx->symref_update_targets,
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+ resolved_ref);
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item->command = TODO_UPDATE_REF;
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strbuf_addf(ctx->buf, "%s\n", decoration->name);
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@@ -6534,6 +6551,7 @@ static int todo_list_add_update_ref_commands(struct todo_list *todo_list)
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struct todo_add_branch_context ctx = {
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.buf = &todo_list->buf,
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.refs_to_oids = STRING_LIST_INIT_DUP,
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+ .symref_update_targets = STRING_LIST_INIT_DUP,
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};
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ctx.items_alloc = 2 * todo_list->nr + 1;
@@ -6559,6 +6577,7 @@ static int todo_list_add_update_ref_commands(struct todo_list *todo_list)
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res = write_update_refs_state(&ctx.refs_to_oids);
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string_list_clear(&ctx.refs_to_oids, 1);
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+ string_list_clear(&ctx.symref_update_targets, 0);
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6582
if (res) {
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/* we failed, so clean up the new list. */
t/t3404-rebase-interactive.sh
+72
@@ -2024,6 +2024,78 @@ test_expect_success '--update-refs updates refs correctly' '
2024
test_cmp expect err.trimmed
2025
'
2026
2027
+test_expect_success '--update-refs checks resolved non-branch symref target' '
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+ test_when_finished "
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+ git worktree remove --force checked-out-target-wt &&
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+ git symbolic-ref -d refs/heads/non-branch-alias &&
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+ git tag -d checked-out-target
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+ " &&
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+ git tag checked-out-target HEAD~1 &&
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+ git symbolic-ref refs/heads/non-branch-alias refs/tags/checked-out-target &&
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+ git worktree add --detach checked-out-target-wt checked-out-target &&
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+ git -C checked-out-target-wt symbolic-ref HEAD refs/tags/checked-out-target &&
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+
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+ GIT_SEQUENCE_EDITOR="cat >todo" git rebase -i --update-refs HEAD~2 &&
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+
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+ test_grep "^# Ref refs/heads/non-branch-alias checked out at" todo &&
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+ test_write_lines refs/tags/checked-out-target >expect &&
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+ git symbolic-ref refs/heads/non-branch-alias >actual &&
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+ test_cmp expect actual
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+'
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+
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+test_expect_success '--update-refs deduplicates non-branch symref targets' '
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+ test_when_finished "
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+ git symbolic-ref -d refs/heads/non-branch-alias-one &&
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+ git symbolic-ref -d refs/heads/non-branch-alias-two &&
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+ git tag -d shared-non-branch-target
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+ " &&
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+ git tag shared-non-branch-target HEAD~1 &&
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+ git symbolic-ref refs/heads/non-branch-alias-one \
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+ refs/tags/shared-non-branch-target &&
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+ git symbolic-ref refs/heads/non-branch-alias-two \
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+ refs/tags/shared-non-branch-target &&
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+
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+ GIT_SEQUENCE_EDITOR=: git rebase -i --force-rebase --update-refs HEAD~2 &&
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+
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+ test_cmp_rev HEAD~1 refs/heads/non-branch-alias-one &&
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+ test_cmp_rev HEAD~1 refs/heads/non-branch-alias-two &&
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+ test_write_lines refs/tags/shared-non-branch-target >expect &&
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+ git symbolic-ref refs/heads/non-branch-alias-one >actual &&
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+ test_cmp expect actual &&
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+ git symbolic-ref refs/heads/non-branch-alias-two >actual &&
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+ test_cmp expect actual
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+'
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+
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+test_expect_success '--update-refs honors non-branch symref reservations' '
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+ test_when_finished "
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+ test_might_fail git worktree remove --force reserved-target-wt &&
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+ test_might_fail git symbolic-ref -d \
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+ refs/heads/reserved-non-branch-alias-one &&
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+ test_might_fail git symbolic-ref -d \
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+ refs/heads/reserved-non-branch-alias-two &&
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+ test_might_fail git tag -d reserved-non-branch-target
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+ " &&
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+ git tag reserved-non-branch-target HEAD~1 &&
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+ git symbolic-ref refs/heads/reserved-non-branch-alias-one \
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+ refs/tags/reserved-non-branch-target &&
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+ git symbolic-ref refs/heads/reserved-non-branch-alias-two \
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+ refs/tags/reserved-non-branch-target &&
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+ git worktree add --detach reserved-target-wt HEAD &&
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+ wt_gitdir=$(git -C reserved-target-wt rev-parse --absolute-git-dir) &&
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+ mkdir -p "$wt_gitdir/rebase-merge" &&
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+ old_oid=$(git rev-parse refs/heads/reserved-non-branch-alias-one) &&
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+ test_write_lines refs/heads/reserved-non-branch-alias-one \
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+ "$old_oid" "$old_oid" >"$wt_gitdir/rebase-merge/update-refs" &&
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+
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+ GIT_SEQUENCE_EDITOR="cat >todo" git rebase -i --update-refs HEAD~2 &&
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+
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+ test_grep "^# Ref refs/heads/reserved-non-branch-alias-one checked out at" \
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+ todo &&
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+ test_grep "^# Ref refs/heads/reserved-non-branch-alias-two checked out at" \
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+ todo &&
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+ test_grep ! "^update-ref refs/heads/reserved-non-branch-alias" todo
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+'
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+
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test_expect_success 'respect user edits to update-ref steps' '
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git checkout -B update-refs-break no-conflict-branch &&
2101
git branch -f base HEAD~4 &&