Lock dispatch manager buffer_lock before accessing buffers;

Only test buffers for UDP dispatches.

(cherry picked from commit 011af4de71)
This commit is contained in:
Mark Andrews
2019-11-22 12:55:03 +11:00
parent dcb21f39b6
commit 1d928de33e

View File

@@ -1513,8 +1513,14 @@ startrecv(dns_dispatch_t *disp, dispsocket_t *dispsock) {
if (disp->recv_pending != 0 && dispsock == NULL)
return (ISC_R_SUCCESS);
if (disp->mgr->buffers >= disp->mgr->maxbuffers)
return (ISC_R_NOMEMORY);
if (disp->socktype == isc_sockettype_udp) {
LOCK(&disp->mgr->buffer_lock);
if (disp->mgr->buffers >= disp->mgr->maxbuffers) {
UNLOCK(&disp->mgr->buffer_lock);
return (ISC_R_NOMEMORY);
}
UNLOCK(&disp->mgr->buffer_lock);
}
if ((disp->attributes & DNS_DISPATCHATTR_EXCLUSIVE) != 0 &&
dispsock == NULL)