[PATCH v3 06/15] remote: handle NULL value for remote.<name>.tagOpt

["Thomas Bachem via GitGitGadget" <gitgitgadget@gmail.com>]

From: Thomas Bachem <mail@thomasbachem.com>

A remote.<name>.tagOpt without a value makes "git fetch",
"git remote" and "git status" segfault: handle_config() passes the
NULL value to strcmp().

The setting takes "--no-tags" or "--tags", and any other value is
ignored. Ignore a missing value too, but warn about it.

Helped-by: Phillip Wood <phillip.wood@dunelm.org.uk>
Assisted-by: Claude Fable 5.1
Assisted-by: Claude Opus 5.5
Signed-off-by: Thomas Bachem <mail@thomasbachem.com>
---
 remote.c          | 4 ++++
 t/t5505-remote.sh | 7 +++++++
 2 files changed, 11 insertions(+)

diff --git a/remote.c b/remote.c
index 49ee2ea318..d3164fee69 100644
--- a/remote.c
+++ b/remote.c
@@ -556,6 +556,10 @@ static int handle_config(const char *key, const char *value,
 		else
 			error(_("more than one uploadpack given, using the first"));
 	} else if (!strcmp(subkey, "tagopt")) {
+		if (!value) {
+			warning(_("missing value for '%s'"), key);
+			return 0;
+		}
 		if (!strcmp(value, "--no-tags"))
 			remote->fetch_tags = -1;
 		else if (!strcmp(value, "--tags"))
diff --git a/t/t5505-remote.sh b/t/t5505-remote.sh
index 5fbfcb0848..8b4c7006ec 100755
--- a/t/t5505-remote.sh
+++ b/t/t5505-remote.sh
@@ -90,6 +90,13 @@ test_expect_success 'remote information for the origin' '
 	)
 '
 
+test_expect_success 'tagOpt without a value only warns' '
+	git -C test -c remote.origin.tagOpt remote >actual 2>err &&
+	echo origin >expect &&
+	test_cmp expect actual &&
+	test_grep "missing value for .remote.origin.tagopt." err
+'
+
 test_expect_success 'add another remote' '
 	(
 		cd test &&
-- 
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