fsck: handle NULL value when parsing message config

When parsing fsck.*, receive.fsck.*, or fetch.fsck.*, we don't check for
an implicit bool. So any of:

  [fsck]
  badTree
  [receive "fsck"]
  badTree
  [fetch "fsck"]
  badTree

will cause us to segfault. We can fix it with config_error_nonbool() in
the usual way, but we have to make a few more changes to get good error
messages. The problem is that all three spots do:

  if (skip_prefix(var, "fsck.", &var))

to match and parse the actual message id. But that means that "var" now
just says "badTree" instead of "receive.fsck.badTree", making the
resulting message confusing. We can fix that by storing the parsed
message id in its own separate variable.

Signed-off-by: Jeff King <peff@peff.net>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

diff --git a/builtin/receive-pack.c b/builtin/receive-pack.c
index 8c4f0cb90a936b2b24b8b7b9e8b1b789c33bff51..ccf9738bce7608613d0e05ef578799c30583b29b 100644 (file)
--- a/builtin/receive-pack.c
+++ b/builtin/receive-pack.c
@@ -142,6 +142,7 @@ static enum deny_action parse_deny_action(const char *var, const char *value)
 static int receive_pack_config(const char *var, const char *value,
                               const struct config_context *ctx, void *cb)
 {
+       const char *msg_id;
        int status = parse_hide_refs_config(var, value, "receive", &hidden_refs);
 
        if (status)
@@ -178,12 +179,14 @@ static int receive_pack_config(const char *var, const char *value,
                return 0;
        }
 
-       if (skip_prefix(var, "receive.fsck.", &var)) {
-               if (is_valid_msg_type(var, value))
+       if (skip_prefix(var, "receive.fsck.", &msg_id)) {
+               if (!value)
+                       return config_error_nonbool(var);
+               if (is_valid_msg_type(msg_id, value))
                        strbuf_addf(&fsck_msg_types, "%c%s=%s",
-                               fsck_msg_types.len ? ',' : '=', var, value);
+                               fsck_msg_types.len ? ',' : '=', msg_id, value);
                else
-                       warning("skipping unknown msg id '%s'", var);
+                       warning("skipping unknown msg id '%s'", msg_id);
                return 0;
        }
 

diff --git a/fetch-pack.c b/fetch-pack.c
index 26999e3b6591313a18df430170aaf935d2e24c14..31a72d43dea802840e25863ca38f3c6b46df3863 100644 (file)
--- a/fetch-pack.c
+++ b/fetch-pack.c
@@ -1862,6 +1862,8 @@ static struct ref *do_fetch_pack_v2(struct fetch_pack_args *args,
 static int fetch_pack_config_cb(const char *var, const char *value,
                                const struct config_context *ctx, void *cb)
 {
+       const char *msg_id;
+
        if (strcmp(var, "fetch.fsck.skiplist") == 0) {
                const char *path;
 
@@ -1873,12 +1875,14 @@ static int fetch_pack_config_cb(const char *var, const char *value,
                return 0;
        }
 
-       if (skip_prefix(var, "fetch.fsck.", &var)) {
-               if (is_valid_msg_type(var, value))
+       if (skip_prefix(var, "fetch.fsck.", &msg_id)) {
+               if (!value)
+                       return config_error_nonbool(var);
+               if (is_valid_msg_type(msg_id, value))
                        strbuf_addf(&fsck_msg_types, "%c%s=%s",
-                               fsck_msg_types.len ? ',' : '=', var, value);
+                               fsck_msg_types.len ? ',' : '=', msg_id, value);
                else
-                       warning("Skipping unknown msg id '%s'", var);
+                       warning("Skipping unknown msg id '%s'", msg_id);
                return 0;
        }
 

diff --git a/fsck.c b/fsck.c
index 6a0bbc50877710ff22db33adec48f4a469143c37..b624083a132cd462ad4e4fc062d2e57aa9fcd852 100644 (file)
--- a/fsck.c
+++ b/fsck.c
@@ -1403,6 +1403,8 @@ int git_fsck_config(const char *var, const char *value,
                    const struct config_context *ctx, void *cb)
 {
        struct fsck_options *options = cb;
+       const char *msg_id;
+
        if (strcmp(var, "fsck.skiplist") == 0) {
                const char *path;
                struct strbuf sb = STRBUF_INIT;
@@ -1416,8 +1418,10 @@ int git_fsck_config(const char *var, const char *value,
                return 0;
        }
 
-       if (skip_prefix(var, "fsck.", &var)) {
-               fsck_set_msg_type(options, var, value);
+       if (skip_prefix(var, "fsck.", &msg_id)) {
+               if (!value)
+                       return config_error_nonbool(var);
+               fsck_set_msg_type(options, msg_id, value);
                return 0;
        }