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/include/linux/ceph/libceph.h b/include/linux/ceph/libceph.h
index 85ae9a8..d73a569 100644
--- a/include/linux/ceph/libceph.h
+++ b/include/linux/ceph/libceph.h
@@ -43,9 +43,9 @@
int flags;
struct ceph_fsid fsid;
struct ceph_entity_addr my_addr;
- int mount_timeout;
- int osd_idle_ttl;
- int osd_keepalive_timeout;
+ unsigned long mount_timeout; /* jiffies */
+ unsigned long osd_idle_ttl; /* jiffies */
+ unsigned long osd_keepalive_timeout; /* jiffies */
/*
* any type that can't be simply compared or doesn't need need
@@ -63,9 +63,9 @@
/*
* defaults
*/
-#define CEPH_MOUNT_TIMEOUT_DEFAULT 60
-#define CEPH_OSD_KEEPALIVE_DEFAULT 5
-#define CEPH_OSD_IDLE_TTL_DEFAULT 60
+#define CEPH_MOUNT_TIMEOUT_DEFAULT msecs_to_jiffies(60 * 1000)
+#define CEPH_OSD_KEEPALIVE_DEFAULT msecs_to_jiffies(5 * 1000)
+#define CEPH_OSD_IDLE_TTL_DEFAULT msecs_to_jiffies(60 * 1000)
#define CEPH_MSG_MAX_FRONT_LEN (16*1024*1024)
#define CEPH_MSG_MAX_MIDDLE_LEN (16*1024*1024)
@@ -93,6 +93,11 @@
CEPH_MOUNT_SHUTDOWN,
};
+static inline unsigned long ceph_timeout_jiffies(unsigned long timeout)
+{
+ return timeout ?: MAX_SCHEDULE_TIMEOUT;
+}
+
struct ceph_mds_client;
/*