freshlybakedca.ke
Git fork
remote-curl: error on incomplete packet
Currently, remote-curl acts as a proxy and blindly forwards packets
between an HTTP server and fetch-pack. In the case of a stateless RPC
connection where the connection is terminated with a partially written
packet, remote-curl will blindly send the partially written packet
before waiting on more input from fetch-pack. Meanwhile, fetch-pack will
read the partial packet and continue reading, expecting more input. This
results in a deadlock between the two processes.
For a stateless connection, inspect packets before sending them and
error out if a packet line packet is incomplete.
Helped-by: Jeff King <peff@peff.net>
Signed-off-by: Denton Liu <liu.denton@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
authored by
Denton Liu
and committed by
Junio C Hamano
74b082ad
101736a1
+56
-3
remote-curl.c
+56
-3
remote-curl.c
···
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}
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#endif
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struct check_pktline_state {
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char len_buf[4];
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int len_filled;
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int remaining;
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};
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+
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static void check_pktline(struct check_pktline_state *state, const char *ptr, size_t size)
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{
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while (size) {
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if (!state->remaining) {
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int digits_remaining = 4 - state->len_filled;
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if (digits_remaining > size)
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digits_remaining = size;
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memcpy(&state->len_buf[state->len_filled], ptr, digits_remaining);
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state->len_filled += digits_remaining;
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ptr += digits_remaining;
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size -= digits_remaining;
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if (state->len_filled == 4) {
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state->remaining = packet_length(state->len_buf);
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if (state->remaining < 0) {
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die(_("remote-curl: bad line length character: %.4s"), state->len_buf);
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} else if (state->remaining < 4) {
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state->remaining = 0;
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} else {
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state->remaining -= 4;
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}
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state->len_filled = 0;
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}
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}
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if (state->remaining) {
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int remaining = state->remaining;
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if (remaining > size)
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remaining = size;
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ptr += remaining;
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size -= remaining;
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state->remaining -= remaining;
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}
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}
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}
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struct rpc_in_data {
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struct rpc_state *rpc;
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struct active_request_slot *slot;
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int check_pktline;
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struct check_pktline_state pktline_state;
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};
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/*
···
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return size;
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if (size)
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data->rpc->any_written = 1;
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if (data->check_pktline)
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check_pktline(&data->pktline_state, ptr, size);
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write_or_die(data->rpc->in, ptr, size);
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return size;
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}
···
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* If flush_received is true, do not attempt to read any more; just use what's
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* in rpc->buf.
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*/
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-
static int post_rpc(struct rpc_state *rpc, int flush_received)
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static int post_rpc(struct rpc_state *rpc, int stateless_connect, int flush_received)
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{
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struct active_request_slot *slot;
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struct curl_slist *headers = http_copy_default_headers();
···
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curl_easy_setopt(slot->curl, CURLOPT_WRITEFUNCTION, rpc_in);
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rpc_in_data.rpc = rpc;
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rpc_in_data.slot = slot;
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rpc_in_data.check_pktline = stateless_connect;
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memset(&rpc_in_data.pktline_state, 0, sizeof(rpc_in_data.pktline_state));
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curl_easy_setopt(slot->curl, CURLOPT_FILE, &rpc_in_data);
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curl_easy_setopt(slot->curl, CURLOPT_FAILONERROR, 0);
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···
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if (!rpc->any_written)
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err = -1;
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if (rpc_in_data.pktline_state.len_filled)
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err = error(_("%d bytes of length header were received"), rpc_in_data.pktline_state.len_filled);
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if (rpc_in_data.pktline_state.remaining)
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err = error(_("%d bytes of body are still expected"), rpc_in_data.pktline_state.remaining);
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curl_slist_free_all(headers);
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free(gzip_body);
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return err;
···
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break;
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rpc->pos = 0;
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rpc->len = n;
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-
err |= post_rpc(rpc, 0);
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err |= post_rpc(rpc, 0, 0);
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}
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close(client.in);
···
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BUG("The entire rpc->buf should be larger than LARGE_PACKET_MAX");
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if (status == PACKET_READ_EOF)
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break;
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-
if (post_rpc(&rpc, status == PACKET_READ_FLUSH))
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if (post_rpc(&rpc, 1, status == PACKET_READ_FLUSH))
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/* We would have an err here */
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break;
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/* Reset the buffer for next request */
+2
t/lib-httpd.sh
+2
t/lib-httpd.sh
···
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prepare_httpd() {
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mkdir -p "$HTTPD_DOCUMENT_ROOT_PATH"
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cp "$TEST_PATH"/passwd "$HTTPD_ROOT_PATH"
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install_script incomplete-length-upload-pack-v2-http.sh
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install_script incomplete-body-upload-pack-v2-http.sh
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install_script broken-smart-http.sh
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install_script error-smart-http.sh
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install_script error.sh
+8
t/lib-httpd/apache.conf
+8
t/lib-httpd/apache.conf
···
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SetEnv GIT_EXEC_PATH ${GIT_EXEC_PATH}
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SetEnv GIT_HTTP_EXPORT_ALL
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</LocationMatch>
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ScriptAlias /smart/incomplete_length/git-upload-pack incomplete-length-upload-pack-v2-http.sh/
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ScriptAlias /smart/incomplete_body/git-upload-pack incomplete-body-upload-pack-v2-http.sh/
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ScriptAliasMatch /error_git_upload_pack/(.*)/git-upload-pack error.sh/
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ScriptAliasMatch /smart_*[^/]*/(.*) ${GIT_EXEC_PATH}/git-http-backend/$1
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ScriptAlias /broken_smart/ broken-smart-http.sh/
···
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<Directory ${GIT_EXEC_PATH}>
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Options FollowSymlinks
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</Directory>
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<Files incomplete-length-upload-pack-v2-http.sh>
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Options ExecCGI
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</Files>
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<Files incomplete-body-upload-pack-v2-http.sh>
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Options ExecCGI
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</Files>
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<Files broken-smart-http.sh>
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Options ExecCGI
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</Files>
+3
t/lib-httpd/incomplete-body-upload-pack-v2-http.sh
+3
t/lib-httpd/incomplete-body-upload-pack-v2-http.sh
+3
t/lib-httpd/incomplete-length-upload-pack-v2-http.sh
+3
t/lib-httpd/incomplete-length-upload-pack-v2-http.sh
+34
t/t5702-protocol-v2.sh
+34
t/t5702-protocol-v2.sh
···
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! grep "Send header: Transfer-Encoding: chunked" log
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'
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test_expect_success 'clone repository with http:// using protocol v2 with incomplete pktline length' '
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test_when_finished "rm -f log" &&
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+
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git init "$HTTPD_DOCUMENT_ROOT_PATH/incomplete_length" &&
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test_commit -C "$HTTPD_DOCUMENT_ROOT_PATH/incomplete_length" file &&
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+
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test_must_fail env GIT_TRACE_PACKET="$(pwd)/log" GIT_TRACE_CURL="$(pwd)/log" git -c protocol.version=2 \
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clone "$HTTPD_URL/smart/incomplete_length" incomplete_length_child 2>err &&
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+
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# Client requested to use protocol v2
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grep "Git-Protocol: version=2" log &&
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# Server responded using protocol v2
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grep "git< version 2" log &&
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# Client reported appropriate failure
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test_i18ngrep "bytes of length header were received" err
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'
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+
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test_expect_success 'clone repository with http:// using protocol v2 with incomplete pktline body' '
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test_when_finished "rm -f log" &&
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+
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git init "$HTTPD_DOCUMENT_ROOT_PATH/incomplete_body" &&
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test_commit -C "$HTTPD_DOCUMENT_ROOT_PATH/incomplete_body" file &&
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+
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test_must_fail env GIT_TRACE_PACKET="$(pwd)/log" GIT_TRACE_CURL="$(pwd)/log" git -c protocol.version=2 \
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clone "$HTTPD_URL/smart/incomplete_body" incomplete_body_child 2>err &&
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+
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# Client requested to use protocol v2
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grep "Git-Protocol: version=2" log &&
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# Server responded using protocol v2
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grep "git< version 2" log &&
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# Client reported appropriate failure
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test_i18ngrep "bytes of body are still expected" err
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'
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+
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test_expect_success 'clone big repository with http:// using protocol v2' '
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test_when_finished "rm -f log" &&
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