2 files changed, 40 insertions, 27 deletions

diff --git a/ipc/compat.c b/ipc/compat.c
index 4d20cfd..fa18141 100644
--- a/ipc/compat.c
+++ b/ipc/compat.c
@@ -115,7 +115,6 @@ struct compat_shm_info {
 
 extern int sem_ctls[];
 #define sc_semopm	(sem_ctls[2])
-#define MAXBUF (64*1024)
 
 static inline int compat_ipc_parse_version(int *cmd)
 {
@@ -307,35 +306,30 @@ long compat_sys_semctl(int first, int second, int third, void __user *uptr)
 
 long compat_sys_msgsnd(int first, int second, int third, void __user *uptr)
 {
-	struct msgbuf __user *p;
 	struct compat_msgbuf __user *up = uptr;
 	long type;
 
 	if (first < 0)
 		return -EINVAL;
-	if (second < 0 || (second >= MAXBUF - sizeof(struct msgbuf)))
+	if (second < 0)
 		return -EINVAL;
 
-	p = compat_alloc_user_space(second + sizeof(struct msgbuf));
-	if (get_user(type, &up->mtype) ||
-	    put_user(type, &p->mtype) ||
-	    copy_in_user(p->mtext, up->mtext, second))
+	if (get_user(type, &up->mtype))
 		return -EFAULT;
 
-	return sys_msgsnd(first, p, second, third);
+	return do_msgsnd(first, type, up->mtext, second, third);
 }
 
 long compat_sys_msgrcv(int first, int second, int msgtyp, int third,
 			   int version, void __user *uptr)
 {
-	struct msgbuf __user *p;
 	struct compat_msgbuf __user *up;
 	long type;
 	int err;
 
 	if (first < 0)
 		return -EINVAL;
-	if (second < 0 || (second >= MAXBUF - sizeof(struct msgbuf)))
+	if (second < 0)
 		return -EINVAL;
 
 	if (!version) {
@@ -349,14 +343,11 @@ long compat_sys_msgrcv(int first, int second, int msgtyp, int third,
 		uptr = compat_ptr(ipck.msgp);
 		msgtyp = ipck.msgtyp;
 	}
-	p = compat_alloc_user_space(second + sizeof(struct msgbuf));
-	err = sys_msgrcv(first, p, second, msgtyp, third);
+	up = uptr;
+	err = do_msgrcv(first, &type, up->mtext, second, msgtyp, third);
 	if (err < 0)
 		goto out;
-	up = uptr;
-	if (get_user(type, &p->mtype) ||
-	    put_user(type, &up->mtype) ||
-	    copy_in_user(up->mtext, p->mtext, err))
+	if (put_user(type, &up->mtype))
 		err = -EFAULT;
 out:
 	return err;
diff --git a/ipc/msg.c b/ipc/msg.c
index 1266b1d..a388824 100644
--- a/ipc/msg.c
+++ b/ipc/msg.c
@@ -626,12 +626,11 @@ static inline int pipelined_send(struct msg_queue *msq, struct msg_msg *msg)
 	return 0;
 }
 
-asmlinkage long
-sys_msgsnd(int msqid, struct msgbuf __user *msgp, size_t msgsz, int msgflg)
+long do_msgsnd(int msqid, long mtype, void __user *mtext,
+		size_t msgsz, int msgflg)
 {
 	struct msg_queue *msq;
 	struct msg_msg *msg;
-	long mtype;
 	int err;
 	struct ipc_namespace *ns;
 
@@ -639,12 +638,10 @@ sys_msgsnd(int msqid, struct msgbuf __user *msgp, size_t msgsz, int msgflg)
 
 	if (msgsz > ns->msg_ctlmax || (long) msgsz < 0 || msqid < 0)
 		return -EINVAL;
-	if (get_user(mtype, &msgp->mtype))
-		return -EFAULT;
 	if (mtype < 1)
 		return -EINVAL;
 
-	msg = load_msg(msgp->mtext, msgsz);
+	msg = load_msg(mtext, msgsz);
 	if (IS_ERR(msg))
 		return PTR_ERR(msg);
 
@@ -723,6 +720,16 @@ out_free:
 	return err;
 }
 
+asmlinkage long
+sys_msgsnd(int msqid, struct msgbuf __user *msgp, size_t msgsz, int msgflg)
+{
+	long mtype;
+
+	if (get_user(mtype, &msgp->mtype))
+		return -EFAULT;
+	return do_msgsnd(msqid, mtype, msgp->mtext, msgsz, msgflg);
+}
+
 static inline int convert_mode(long *msgtyp, int msgflg)
 {
 	/*
@@ -742,8 +749,8 @@ static inline int convert_mode(long *msgtyp, int msgflg)
 	return SEARCH_EQUAL;
 }
 
-asmlinkage long sys_msgrcv(int msqid, struct msgbuf __user *msgp, size_t msgsz,
-			   long msgtyp, int msgflg)
+long do_msgrcv(int msqid, long *pmtype, void __user *mtext,
+		size_t msgsz, long msgtyp, int msgflg)
 {
 	struct msg_queue *msq;
 	struct msg_msg *msg;
@@ -889,15 +896,30 @@ out_unlock:
 		return PTR_ERR(msg);
 
 	msgsz = (msgsz > msg->m_ts) ? msg->m_ts : msgsz;
-	if (put_user (msg->m_type, &msgp->mtype) ||
-	    store_msg(msgp->mtext, msg, msgsz)) {
+	*pmtype = msg->m_type;
+	if (store_msg(mtext, msg, msgsz))
 		msgsz = -EFAULT;
-	}
+
 	free_msg(msg);
 
 	return msgsz;
 }
 
+asmlinkage long sys_msgrcv(int msqid, struct msgbuf __user *msgp, size_t msgsz,
+			   long msgtyp, int msgflg)
+{
+	long err, mtype;
+
+	err =  do_msgrcv(msqid, &mtype, msgp->mtext, msgsz, msgtyp, msgflg);
+	if (err < 0)
+		goto out;
+
+	if (put_user(mtype, &msgp->mtype))
+		err = -EFAULT;
+out:
+	return err;
+}
+
 #ifdef CONFIG_PROC_FS
 static int sysvipc_msg_proc_show(struct seq_file *s, void *it)
 {