[PATCH 10/15] setup: handle NULL value for safe.bareRepository

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

From: Thomas Bachem <mail@thomasbachem.com>

A safe.bareRepository without a value makes git segfault in every
bare repository it discovers, as in "git -C repo.git log":
allowed_bare_repo_cb() passes the NULL value to strcmp().

Reject a missing value with config_error_nonbool(). The callback
already fails for any value other than "explicit" and "all".

Assisted-by: Claude Opus 5.5
Signed-off-by: Thomas Bachem <mail@thomasbachem.com>
---
 setup.c                         | 2 ++
 t/t0035-safe-bare-repository.sh | 6 ++++++
 2 files changed, 8 insertions(+)

diff --git a/setup.c b/setup.c
index 29474fc292..567a44bcb7 100644
--- a/setup.c
+++ b/setup.c
@@ -1472,6 +1472,8 @@ static int allowed_bare_repo_cb(const char *key, const char *value,
 	if (strcasecmp(key, "safe.bareRepository"))
 		return 0;
 
+	if (!value)
+		return config_error_nonbool(key);
 	if (!strcmp(value, "explicit")) {
 		*allowed_bare_repo = ALLOWED_BARE_REPO_EXPLICIT;
 		return 0;
diff --git a/t/t0035-safe-bare-repository.sh b/t/t0035-safe-bare-repository.sh
index 1d3d19f5b4..a0e0c48d7d 100755
--- a/t/t0035-safe-bare-repository.sh
+++ b/t/t0035-safe-bare-repository.sh
@@ -80,6 +80,12 @@ test_expect_success 'safe.bareRepository on the command line' '
 		-c safe.bareRepository=all
 '
 
+test_expect_success 'safe.bareRepository without a value is rejected' '
+	test_must_fail git -C outer-repo/bare-repo -c safe.bareRepository \
+		rev-parse --git-dir 2>err &&
+	test_grep "missing value for .safe.barerepository." err
+'
+
 test_expect_success 'safe.bareRepository in included file' '
 	cat >gitconfig-include <<-\EOF &&
 	[safe]
-- 
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