[<prev] [next>] [day] [month] [year] [list]
Message-Id: <20230224204855.234010-1-izbyshev@ispras.ru>
Date: Fri, 24 Feb 2023 23:48:55 +0300
From: Alexey Izbyshev <izbyshev@...ras.ru>
To: musl@...ts.openwall.com
Subject: [PATCH] dns: handle early eof in tcp fallback
A zero returned from recvmsg is currently treated as if some data were
received, so if a DNS server closes its TCP socket before sending the
full answer, __res_msend_rc will spin until the timeout elapses because
POLLIN event will be reported on each poll. Fix this by treating an
early EOF as an error.
---
src/network/res_msend.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/src/network/res_msend.c b/src/network/res_msend.c
index fef7e3a2..2643be22 100644
--- a/src/network/res_msend.c
+++ b/src/network/res_msend.c
@@ -287,7 +287,7 @@ int __res_msend_rc(int nqueries, const unsigned char *const *queries,
};
step_mh(&mh, apos[i]);
r = recvmsg(pfd[i].fd, &mh, 0);
- if (r < 0) goto out;
+ if (r <= 0) goto out;
apos[i] += r;
if (apos[i] < 2) continue;
int alen = alen_buf[i][0]*256 + alen_buf[i][1];
--
2.39.1
Powered by blists - more mailing lists
Confused about mailing lists and their use?
Read about mailing lists on Wikipedia
and check out these
guidelines on proper formatting of your messages.
