Index: fs/pipe.c
===================================================================
RCS file: /vger/linux/fs/pipe.c,v
retrieving revision 1.36
diff -u -r1.36 pipe.c
--- pipe.c	1998/03/27 07:01:11	1.36
+++ pipe.c	1998/04/25 14:49:01
@@ -37,7 +37,7 @@
 			 size_t count, loff_t *ppos)
 {
 	struct inode * inode = filp->f_dentry->d_inode;
-	ssize_t chars = 0, size = 0, read = 0;
+	ssize_t chars = 0, size = 0, read = 0, ret = 0;
         char *pipebuf;
 
 	if (ppos != &filp->f_pos)
@@ -68,31 +68,36 @@
 			chars = count;
 		if (chars > size)
 			chars = size;
-		read += chars;
                 pipebuf = PIPE_BASE(*inode)+PIPE_START(*inode);
+		if (copy_to_user(buf, pipebuf, chars )) {
+			ret = -EFAULT;
+			goto out;
+		}
+		read += chars;
 		PIPE_START(*inode) += chars;
 		PIPE_START(*inode) &= (PIPE_BUF-1);
 		PIPE_LEN(*inode) -= chars;
 		count -= chars;
-		copy_to_user(buf, pipebuf, chars );
 		buf += chars;
 	}
+	ret = read;
+	if (!read && PIPE_WRITERS(*inode))
+		ret = -EAGAIN;
+ out:
 	PIPE_LOCK(*inode)--;
-	wake_up_interruptible(&PIPE_WAIT(*inode));
 	if (read) {
+		wake_up_interruptible(&PIPE_WAIT(*inode));
 		UPDATE_ATIME(inode);
-		return read;
 	}
-	if (PIPE_WRITERS(*inode))
-		return -EAGAIN;
-	return 0;
+
+	return ret;
 }
 	
 static ssize_t pipe_write(struct file * filp, const char * buf,
 			  size_t count, loff_t *ppos)
 {
 	struct inode * inode = filp->f_dentry->d_inode;
-	ssize_t chars = 0, free = 0, written = 0;
+	ssize_t chars = 0, free = 0, written = 0, ret = 0;
 	char *pipebuf;
 
 	if (ppos != &filp->f_pos)
@@ -127,19 +132,29 @@
 			if (chars > free)
 				chars = free;
                         pipebuf = PIPE_BASE(*inode)+PIPE_END(*inode);
+			if (copy_from_user(pipebuf, buf, chars )) {
+				ret = -EFAULT;
+				PIPE_LOCK(*inode)--;
+				goto out;
+			}
 			written += chars;
 			PIPE_LEN(*inode) += chars;
 			count -= chars;
-			copy_from_user(pipebuf, buf, chars );
 			buf += chars;
 		}
 		PIPE_LOCK(*inode)--;
 		wake_up_interruptible(&PIPE_WAIT(*inode));
 		free = 1;
+	}
+	ret = written;
+ out:
+	if (written) {
+		inode->i_ctime = inode->i_mtime = CURRENT_TIME;
+		mark_inode_dirty(inode);
+		if (ret != written)
+			wake_up_interruptible(&PIPE_WAIT(*inode));
 	}
-	inode->i_ctime = inode->i_mtime = CURRENT_TIME;
-	mark_inode_dirty(inode);
-	return written;
+	return ret;
 }
 
 static long long pipe_lseek(struct file * file, long long offset, int orig)