libceph: don't access invalid memory in keepalive2 path
This
struct ceph_timespec ceph_ts;
...
con_out_kvec_add(con, sizeof(ceph_ts), &ceph_ts);
wraps ceph_ts into a kvec and adds it to con->out_kvec array, yet
ceph_ts becomes invalid on return from prepare_write_keepalive(). As
a result, we send out bogus keepalive2 stamps. Fix this by encoding
into a ceph_timespec member, similar to how acks are read and written.
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Reviewed-by: Yan, Zheng <zyan@redhat.com>
diff --git a/net/ceph/messenger.c b/net/ceph/messenger.c
index 525f454..b9b0e3b 100644
--- a/net/ceph/messenger.c
+++ b/net/ceph/messenger.c
@@ -1353,11 +1353,12 @@
dout("prepare_write_keepalive %p\n", con);
con_out_kvec_reset(con);
if (con->peer_features & CEPH_FEATURE_MSGR_KEEPALIVE2) {
- struct timespec ts = CURRENT_TIME;
- struct ceph_timespec ceph_ts;
- ceph_encode_timespec(&ceph_ts, &ts);
+ struct timespec now = CURRENT_TIME;
+
con_out_kvec_add(con, sizeof(tag_keepalive2), &tag_keepalive2);
- con_out_kvec_add(con, sizeof(ceph_ts), &ceph_ts);
+ ceph_encode_timespec(&con->out_temp_keepalive2, &now);
+ con_out_kvec_add(con, sizeof(con->out_temp_keepalive2),
+ &con->out_temp_keepalive2);
} else {
con_out_kvec_add(con, sizeof(tag_keepalive), &tag_keepalive);
}