From 156f6a10c21c3501aa3938badf5c3f1339c509a2 Mon Sep 17 00:00:00 2001 From: Eric Blake Date: Wed, 6 Apr 2016 16:48:38 -0600 Subject: [PATCH] nbd: Don't kill server when client requests unknown option nbd-server.c currently fails to handle unsupported options properly. If during option haggling the client sends an unknown request, the server kills the connection instead of letting the client try to fall back to something older. This is precisely what advertising NBD_FLAG_FIXED_NEWSTYLE was supposed to fix. Signed-off-by: Eric Blake Message-Id: <1459982918-32229-1-git-send-email-eblake@redhat.com> Signed-off-by: Paolo Bonzini --- nbd/server.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/nbd/server.c b/nbd/server.c index 6d9c15a0b0..2a4dd10f52 100644 --- a/nbd/server.c +++ b/nbd/server.c @@ -483,9 +483,12 @@ static int nbd_negotiate_options(NBDClient *client) return -EINVAL; default: TRACE("Unsupported option 0x%x", clientflags); + if (nbd_negotiate_drop_sync(client->ioc, length) != length) { + return -EIO; + } nbd_negotiate_send_rep(client->ioc, NBD_REP_ERR_UNSUP, clientflags); - return -EINVAL; + break; } } else { /* -- 2.11.0