1 files changed, 8 insertions, 3 deletions

diff --git a/drivers/md/dm-log-userspace-transfer.c b/drivers/md/dm-log-userspace-transfer.c
index 54abf9e303b7..075cbcf8a9f5 100644
--- a/drivers/md/dm-log-userspace-transfer.c
+++ b/drivers/md/dm-log-userspace-transfer.c
@@ -6,6 +6,7 @@
 
 #include <linux/kernel.h>
 #include <linux/module.h>
+#include <linux/slab.h>
 #include <net/sock.h>
 #include <linux/workqueue.h>
 #include <linux/connector.h>
@@ -172,11 +173,15 @@ int dm_consult_userspace(const char *uuid, uint64_t luid, int request_type,
 {
         int r = 0;
         size_t dummy = 0;
-        int overhead_size =
-                sizeof(struct dm_ulog_request *) + sizeof(struct cn_msg);
+        int overhead_size = sizeof(struct dm_ulog_request) + sizeof(struct cn_msg);
         struct dm_ulog_request *tfr = prealloced_ulog_tfr;
         struct receiving_pkg pkg;
 
+        /*
+         * Given the space needed to hold the 'struct cn_msg' and
+         * 'struct dm_ulog_request' - do we have enough payload
+         * space remaining?
+         */
         if (data_size > (DM_ULOG_PREALLOCED_SIZE - overhead_size)) {
                 DMINFO("Size of tfr exceeds preallocated size");
                 return -EINVAL;
@@ -191,7 +196,7 @@ resend:
          */
         mutex_lock(&dm_ulog_lock);
 
-        memset(tfr, 0, DM_ULOG_PREALLOCED_SIZE - overhead_size);
+        memset(tfr, 0, DM_ULOG_PREALLOCED_SIZE - sizeof(struct cn_msg));
         memcpy(tfr->uuid, uuid, DM_UUID_LEN);
         tfr->luid = luid;
         tfr->seq = dm_ulog_seq++;