block/curl: Improve type safety of s->timeout.
qemu_opt_get_number returns a uint64_t, and curl_easy_setopt expects a
long (not an int). There is no warning about the latter type error
because curl_easy_setopt uses a varargs argument.
Store the timeout (which is a positive number of seconds) as a
uint64_t. Check that the number given by the user is reasonable.
Zero is permissible (meaning no timeout is enforced by cURL).
Cast it to long before calling curl_easy_setopt to fix the type error.
Example error message after this change has been applied:
$ ./qemu-img create -f qcow2 /tmp/test.qcow2 \
-b 'json: { "file.driver":"https",
"file.url":"https://foo/bar",
"file.timeout":-1 }'
qemu-img: /tmp/test.qcow2: Could not open 'json: { "file.driver":"https", "file.url":"https://foo/bar", "file.timeout":-1 }': timeout parameter is too large or negative: Invalid argument
Signed-off-by: Richard W.M. Jones <rjones@redhat.com>
Reviewed-by: Laszlo Ersek <lersek@redhat.com>
Reviewed-by: Gonglei <arei.gonglei@huawei.com>
Signed-off-by: Stefan Hajnoczi <stefanha@redhat.com>
diff --git a/block/curl.c b/block/curl.c
index b4157cc..bbee3ca 100644
--- a/block/curl.c
+++ b/block/curl.c
@@ -64,6 +64,7 @@
#define SECTOR_SIZE 512
#define READ_AHEAD_DEFAULT (256 * 1024)
#define CURL_TIMEOUT_DEFAULT 5
+#define CURL_TIMEOUT_MAX 10000
#define FIND_RET_NONE 0
#define FIND_RET_OK 1
@@ -112,7 +113,7 @@
char *url;
size_t readahead_size;
bool sslverify;
- int timeout;
+ uint64_t timeout;
char *cookie;
bool accept_range;
AioContext *aio_context;
@@ -390,7 +391,7 @@
if (s->cookie) {
curl_easy_setopt(state->curl, CURLOPT_COOKIE, s->cookie);
}
- curl_easy_setopt(state->curl, CURLOPT_TIMEOUT, s->timeout);
+ curl_easy_setopt(state->curl, CURLOPT_TIMEOUT, (long)s->timeout);
curl_easy_setopt(state->curl, CURLOPT_WRITEFUNCTION,
(void *)curl_read_cb);
curl_easy_setopt(state->curl, CURLOPT_WRITEDATA, (void *)state);
@@ -546,6 +547,10 @@
s->timeout = qemu_opt_get_number(opts, CURL_BLOCK_OPT_TIMEOUT,
CURL_TIMEOUT_DEFAULT);
+ if (s->timeout > CURL_TIMEOUT_MAX) {
+ error_setg(errp, "timeout parameter is too large or negative");
+ goto out_noclean;
+ }
s->sslverify = qemu_opt_get_bool(opts, CURL_BLOCK_OPT_SSLVERIFY, true);
