Handle canceled read during sending data over stats channel

An assertion failure would be triggered when the TCP connection
is canceled during sending the data back to the client.

Don't require the state to be `RECV` on non successful read to
gracefully handle canceled TCP connection during the SEND state of the
HTTPD channel.

(cherry picked from commit 6562227cc8a0732002c01cfc045129bf6080b94c)

diff --git a/lib/isc/httpd.c b/lib/isc/httpd.c
index a701fb2a8423d03d504ebf7362f11553ea25d990..134806bea9859c1882797e63fd263a69cd47b34c 100644 (file)
--- a/lib/isc/httpd.c
+++ b/lib/isc/httpd.c
@@ -904,13 +904,14 @@ httpd_request(isc_nmhandle_t *handle, isc_result_t eresult,
 
        httpd = isc_nmhandle_getdata(handle);
 
-       REQUIRE(httpd->state == RECV);
        REQUIRE(httpd->handle == handle);
 
        if (eresult != ISC_R_SUCCESS) {
                goto cleanup_readhandle;
        }
 
+       REQUIRE(httpd->state == RECV);
+
        result = process_request(
                httpd, region == NULL ? &(isc_region_t){ NULL, 0 } : region,
                &buflen);
@@ -1195,7 +1196,6 @@ httpd_senddone(isc_nmhandle_t *handle, isc_result_t result, void *arg) {
        isc_httpd_t *httpd = (isc_httpd_t *)arg;
 
        REQUIRE(VALID_HTTPD(httpd));
-       REQUIRE(httpd->state == SEND);
        REQUIRE(httpd->handle == handle);
 
        isc_buffer_free(&httpd->sendbuffer);
@@ -1222,6 +1222,8 @@ httpd_senddone(isc_nmhandle_t *handle, isc_result_t result, void *arg) {
                goto cleanup_readhandle;
        }
 
+       REQUIRE(httpd->state == SEND);
+
        httpd->state = RECV;
        httpd->sendhandle = NULL;