diff --git a/include/linux/compat.h b/include/linux/compat.h
index 9f68e90a14ec9df63804c66c17db531664745874..f2b8fe20cc8ead2e998799218b91536c72c373b4 100644
--- a/include/linux/compat.h
+++ b/include/linux/compat.h
@@ -266,9 +266,9 @@ long compat_sys_shmat(int first, int second, compat_uptr_t third, int version,
 #else
 long compat_sys_semctl(int semid, int semnum, int cmd, int arg);
 long compat_sys_msgsnd(int msqid, struct compat_msgbuf __user *msgp,
-		size_t msgsz, int msgflg);
+		compat_ssize_t msgsz, int msgflg);
 long compat_sys_msgrcv(int msqid, struct compat_msgbuf __user *msgp,
-		size_t msgsz, long msgtyp, int msgflg);
+		compat_ssize_t msgsz, long msgtyp, int msgflg);
 long compat_sys_shmat(int shmid, compat_uptr_t shmaddr, int shmflg);
 #endif
 long compat_sys_msgctl(int first, int second, void __user *uptr);
diff --git a/ipc/compat.c b/ipc/compat.c
index a41600f6ba525474b3445269fa53623f0b62fe6b..20f92b2f2932537b47a6a175fa30ca14c1aaab29 100644
--- a/ipc/compat.c
+++ b/ipc/compat.c
@@ -373,21 +373,21 @@ long compat_sys_semctl(int semid, int semnum, int cmd, int arg)
 }
 
 long compat_sys_msgsnd(int msqid, struct compat_msgbuf __user *msgp,
-		       size_t msgsz, int msgflg)
+		       compat_ssize_t msgsz, int msgflg)
 {
 	compat_long_t mtype;
 
 	if (get_user(mtype, &msgp->mtype))
 		return -EFAULT;
-	return do_msgsnd(msqid, mtype, msgp->mtext, msgsz, msgflg);
+	return do_msgsnd(msqid, mtype, msgp->mtext, (ssize_t)msgsz, msgflg);
 }
 
 long compat_sys_msgrcv(int msqid, struct compat_msgbuf __user *msgp,
-		       size_t msgsz, long msgtyp, int msgflg)
+		       compat_ssize_t msgsz, long msgtyp, int msgflg)
 {
 	long err, mtype;
 
-	err =  do_msgrcv(msqid, &mtype, msgp->mtext, msgsz, msgtyp, msgflg);
+	err =  do_msgrcv(msqid, &mtype, msgp->mtext, (ssize_t)msgsz, msgtyp, msgflg);
 	if (err < 0)
 		goto out;