Read lock around files->fd[] accesses.

arch/sparc64/solaris/ioctl.c

@@ -289,11 +289,15 @@ static inline int solaris_sockmod(unsigned int fd, unsigned int cmd, u32 arg)
 {
 	struct inode *ino;
 	/* I wonder which of these tests are superfluous... --patrik */
+	read_lock(&current->files->file_lock);
 	if (! current->files->fd[fd] ||
 	    ! current->files->fd[fd]->f_dentry ||
 	    ! (ino = current->files->fd[fd]->f_dentry->d_inode) ||
-	    ! ino->i_sock)
+	    ! ino->i_sock) {
+		read_unlock(&current->files->file_lock);
 		return TBADF;
+	}
+	read_unlock(&current->files->file_lock);
 	
 	switch (cmd & 0xff) {
 	case 109: /* SI_SOCKPARAMS */