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>
This commit is contained in:
Richard W.M. Jones 2014-10-26 11:05:27 +00:00 committed by Stefan Hajnoczi
parent 3432a1929e
commit f76faeda4b

View File

@ -64,6 +64,7 @@ static CURLMcode __curl_multi_socket_action(CURLM *multi_handle,
#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 @@ typedef struct BDRVCURLState {
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 @@ static CURLState *curl_init_state(BlockDriverState *bs, BDRVCURLState *s)
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 @@ static int curl_open(BlockDriverState *bs, QDict *options, int flags,
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);