nbd: Don't crash when server reports NBD_CMD_READ failure

If a server fails a read, for example with EIO, but the connection
is still live, then we would crash trying to print a non-existent
error message in nbd_client_co_preadv().  For consistency, also
change the error printout in nbd_read_reply_entry(), although that
instance does not crash.  Bug introduced in commit f140e300.

Signed-off-by: Eric Blake <eblake@redhat.com>
Message-Id: <20171112013936.5942-1-eblake@redhat.com>
Reviewed-by: Vladimir Sementsov-Ogievskiy <vsementsov@virtuozzo.com>
This commit is contained in:
Eric Blake 2017-11-11 19:39:36 -06:00
parent fec035a53f
commit 08ace1d753

View File

@ -78,7 +78,7 @@ static coroutine_fn void nbd_read_reply_entry(void *opaque)
while (!s->quit) {
assert(s->reply.handle == 0);
ret = nbd_receive_reply(s->ioc, &s->reply, &local_err);
if (ret < 0) {
if (local_err) {
error_report_err(local_err);
}
if (ret <= 0) {
@ -691,7 +691,7 @@ int nbd_client_co_preadv(BlockDriverState *bs, uint64_t offset,
ret = nbd_co_receive_cmdread_reply(client, request.handle, offset, qiov,
&local_err);
if (ret < 0) {
if (local_err) {
error_report_err(local_err);
}
return ret;