libceph: store timeouts in jiffies, verify user input
There are currently three libceph-level timeouts that the user can
specify on mount: mount_timeout, osd_idle_ttl and osdkeepalive. All of
these are in seconds and no checking is done on user input: negative
values are accepted, we multiply them all by HZ which may or may not
overflow, arbitrarily large jiffies then get added together, etc.
There is also a bug in the way mount_timeout=0 is handled. It's
supposed to mean "infinite timeout", but that's not how wait.h APIs
treat it and so __ceph_open_session() for example will busy loop
without much chance of being interrupted if none of ceph-mons are
there.
Fix all this by verifying user input, storing timeouts capped by
msecs_to_jiffies() in jiffies and using the new ceph_timeout_jiffies()
helper for all user-specified waits to handle infinite timeouts
correctly.
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Reviewed-by: Alex Elder <elder@linaro.org>
diff --git a/fs/ceph/mds_client.c b/fs/ceph/mds_client.c
index 69a36f4..0b0e0a9 100644
--- a/fs/ceph/mds_client.c
+++ b/fs/ceph/mds_client.c
@@ -2268,7 +2268,8 @@
dout("do_request waiting\n");
if (req->r_timeout) {
err = (long)wait_for_completion_killable_timeout(
- &req->r_completion, req->r_timeout);
+ &req->r_completion,
+ ceph_timeout_jiffies(req->r_timeout));
if (err == 0)
err = -EIO;
} else if (req->r_wait_for_completion) {
@@ -3424,8 +3425,8 @@
*/
static void wait_requests(struct ceph_mds_client *mdsc)
{
+ struct ceph_options *opts = mdsc->fsc->client->options;
struct ceph_mds_request *req;
- struct ceph_fs_client *fsc = mdsc->fsc;
mutex_lock(&mdsc->mutex);
if (__get_oldest_req(mdsc)) {
@@ -3433,7 +3434,7 @@
dout("wait_requests waiting for requests\n");
wait_for_completion_timeout(&mdsc->safe_umount_waiters,
- fsc->client->options->mount_timeout * HZ);
+ ceph_timeout_jiffies(opts->mount_timeout));
/* tear down remaining requests */
mutex_lock(&mdsc->mutex);
@@ -3556,10 +3557,9 @@
*/
void ceph_mdsc_close_sessions(struct ceph_mds_client *mdsc)
{
+ struct ceph_options *opts = mdsc->fsc->client->options;
struct ceph_mds_session *session;
int i;
- struct ceph_fs_client *fsc = mdsc->fsc;
- unsigned long timeout = fsc->client->options->mount_timeout * HZ;
dout("close_sessions\n");
@@ -3580,7 +3580,7 @@
dout("waiting for sessions to close\n");
wait_event_timeout(mdsc->session_close_wq, done_closing_sessions(mdsc),
- timeout);
+ ceph_timeout_jiffies(opts->mount_timeout));
/* tear down remaining sessions */
mutex_lock(&mdsc->mutex);