reftable: reject 0 object_id_len

[thirdparty/git.git] / ls-refs.c

diff --git a/ls-refs.c b/ls-refs.c
index 88f6c3f60d8ef61373a1bfed33f49c877b6af320..54078323dcb92b68463e6c16b23621ae8f47a2f1 100644 (file)
--- a/ls-refs.c
+++ b/ls-refs.c
@@ -40,6 +40,12 @@ static void ensure_config_read(void)
        config_read = 1;
 }
 
+/*
+ * If we see this many or more "ref-prefix" lines from the client, we consider
+ * it "too many" and will avoid using the prefix feature entirely.
+ */
+#define TOO_MANY_PREFIXES 65536
+
 /*
  * Check if one of the prefixes is a prefix of the ref.
  * If no prefixes were provided, all refs match.
@@ -65,6 +71,7 @@ struct ls_refs_data {
        unsigned peel;
        unsigned symrefs;
        struct strvec prefixes;
+       struct strbuf buf;
        unsigned unborn : 1;
 };
 
@@ -73,7 +80,8 @@ static int send_ref(const char *refname, const struct object_id *oid,
 {
        struct ls_refs_data *data = cb_data;
        const char *refname_nons = strip_namespace(refname);
-       struct strbuf refline = STRBUF_INIT;
+
+       strbuf_reset(&data->buf);
 
        if (ref_is_hidden(refname_nons, refname))
                return 0;
@@ -82,9 +90,9 @@ static int send_ref(const char *refname, const struct object_id *oid,
                return 0;
 
        if (oid)
-               strbuf_addf(&refline, "%s %s", oid_to_hex(oid), refname_nons);
+               strbuf_addf(&data->buf, "%s %s", oid_to_hex(oid), refname_nons);
        else
-               strbuf_addf(&refline, "unborn %s", refname_nons);
+               strbuf_addf(&data->buf, "unborn %s", refname_nons);
        if (data->symrefs && flag & REF_ISSYMREF) {
                struct object_id unused;
                const char *symref_target = resolve_ref_unsafe(refname, 0,
@@ -94,20 +102,19 @@ static int send_ref(const char *refname, const struct object_id *oid,
                if (!symref_target)
                        die("'%s' is a symref but it is not?", refname);
 
-               strbuf_addf(&refline, " symref-target:%s",
+               strbuf_addf(&data->buf, " symref-target:%s",
                            strip_namespace(symref_target));
        }
 
        if (data->peel && oid) {
                struct object_id peeled;
                if (!peel_iterated_oid(oid, &peeled))
-                       strbuf_addf(&refline, " peeled:%s", oid_to_hex(&peeled));
+                       strbuf_addf(&data->buf, " peeled:%s", oid_to_hex(&peeled));
        }
 
-       strbuf_addch(&refline, '\n');
-       packet_write(1, refline.buf, refline.len);
+       strbuf_addch(&data->buf, '\n');
+       packet_fwrite(stdout, data->buf.buf, data->buf.len);
 
-       strbuf_release(&refline);
        return 0;
 }
 
@@ -138,13 +145,13 @@ static int ls_refs_config(const char *var, const char *value, void *data)
        return parse_hide_refs_config(var, value, "uploadpack");
 }
 
-int ls_refs(struct repository *r, struct strvec *keys,
-           struct packet_reader *request)
+int ls_refs(struct repository *r, struct packet_reader *request)
 {
        struct ls_refs_data data;
 
        memset(&data, 0, sizeof(data));
        strvec_init(&data.prefixes);
+       strbuf_init(&data.buf, 0);
 
        ensure_config_read();
        git_config(ls_refs_config, NULL);
@@ -157,22 +164,35 @@ int ls_refs(struct repository *r, struct strvec *keys,
                        data.peel = 1;
                else if (!strcmp("symrefs", arg))
                        data.symrefs = 1;
-               else if (skip_prefix(arg, "ref-prefix ", &out))
-                       strvec_push(&data.prefixes, out);
+               else if (skip_prefix(arg, "ref-prefix ", &out)) {
+                       if (data.prefixes.nr < TOO_MANY_PREFIXES)
+                               strvec_push(&data.prefixes, out);
+               }
                else if (!strcmp("unborn", arg))
                        data.unborn = allow_unborn;
+               else
+                       die(_("unexpected line: '%s'"), arg);
        }
 
        if (request->status != PACKET_READ_FLUSH)
                die(_("expected flush after ls-refs arguments"));
 
+       /*
+        * If we saw too many prefixes, we must avoid using them at all; as
+        * soon as we have any prefix, they are meant to form a comprehensive
+        * list.
+        */
+       if (data.prefixes.nr >= TOO_MANY_PREFIXES)
+               strvec_clear(&data.prefixes);
+
        send_possibly_unborn_head(&data);
        if (!data.prefixes.nr)
                strvec_push(&data.prefixes, "");
        for_each_fullref_in_prefixes(get_git_namespace(), data.prefixes.v,
-                                    send_ref, &data, 0);
-       packet_flush(1);
+                                    send_ref, &data);
+       packet_fflush(stdout);
        strvec_clear(&data.prefixes);
+       strbuf_release(&data.buf);
        return 0;
 }