From 4e7676571bccb42dd49b5efbb91ac49077ea5197 Mon Sep 17 00:00:00 2001 From: Max Reitz Date: Tue, 25 Oct 2016 04:54:29 +0200 Subject: block/curl: Fix return value from curl_read_cb While commit 38bbc0a580f9f10570b1d1b5d3e92f0e6feb2970 is correct in that the callback is supposed to return the number of bytes handled; what it does not mention is that libcurl will throw an error if the callback did not "handle" all of the data passed to it. Therefore, if the callback receives some data that it cannot handle (either because the receive buffer has not been set up yet or because it would not fit into the receive buffer) and we have to ignore it, we still have to report that the data has been handled. Obviously, this should not happen normally. But it does happen at least for FTP connections where some data (that we do not expect) may be generated when the connection is established. Cc: qemu-stable@nongnu.org Signed-off-by: Max Reitz Reviewed-by: Eric Blake Message-id: 20161025025431.24714-3-mreitz@redhat.com Signed-off-by: Jeff Cody --- block/curl.c | 11 +++++++---- 1 file changed, 7 insertions(+), 4 deletions(-) (limited to 'block/curl.c') diff --git a/block/curl.c b/block/curl.c index 1d19e64f0f..7a7e831866 100644 --- a/block/curl.c +++ b/block/curl.c @@ -211,12 +211,13 @@ static size_t curl_read_cb(void *ptr, size_t size, size_t nmemb, void *opaque) DPRINTF("CURL: Just reading %zd bytes\n", realsize); - if (!s || !s->orig_buf) - return 0; + if (!s || !s->orig_buf) { + goto read_end; + } if (s->buf_off >= s->buf_len) { /* buffer full, read nothing */ - return 0; + goto read_end; } realsize = MIN(realsize, s->buf_len - s->buf_off); memcpy(s->orig_buf + s->buf_off, ptr, realsize); @@ -237,7 +238,9 @@ static size_t curl_read_cb(void *ptr, size_t size, size_t nmemb, void *opaque) } } - return realsize; +read_end: + /* curl will error out if we do not return this value */ + return size * nmemb; } static int curl_find_buf(BDRVCURLState *s, size_t start, size_t len, -- cgit v1.2.3