Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S267313AbUIFVkn (ORCPT ); Mon, 6 Sep 2004 17:40:43 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S267350AbUIFVkn (ORCPT ); Mon, 6 Sep 2004 17:40:43 -0400 Received: from mail.dif.dk ([193.138.115.101]:24742 "EHLO mail.dif.dk") by vger.kernel.org with ESMTP id S267313AbUIFVki (ORCPT ); Mon, 6 Sep 2004 17:40:38 -0400 Date: Mon, 6 Sep 2004 23:46:47 +0200 (CEST) From: Jesper Juhl To: Jens Axboe Cc: LKML Subject: [PATCH] remember to check return value from __copy_to_user() in cdrom_read_cdda_old() Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: linux-kernel-owner@vger.kernel.org X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1394 Lines: 41 Hi, Here's a patch to ensure that the return value from __copy_to_user() gets checked in cdrom_read_cdda_old(). I assume that returning -EFAULT if the copy fails to copy all bytes is an appropriate action, but please correct me if I'm wrong. Signed-off-by: Jesper Juhl diff -up linux-2.6.9-rc1-bk13-orig/drivers/cdrom/cdrom.c linux-2.6.9-rc1-bk13/drivers/cdrom/cdrom.c --- linux-2.6.9-rc1-bk13-orig/drivers/cdrom/cdrom.c 2004-08-24 20:44:01.000000000 +0200 +++ linux-2.6.9-rc1-bk13/drivers/cdrom/cdrom.c 2004-09-06 23:41:20.000000000 +0200 @@ -1959,7 +1959,10 @@ static int cdrom_read_cdda_old(struct cd ret = cdrom_read_block(cdi, &cgc, lba, nr, 1, CD_FRAMESIZE_RAW); if (ret) break; - __copy_to_user(ubuf, cgc.buffer, CD_FRAMESIZE_RAW * nr); + if (__copy_to_user(ubuf, cgc.buffer, CD_FRAMESIZE_RAW * nr)) { + kfree(cgc.buffer); + return -EFAULT; + } ubuf += CD_FRAMESIZE_RAW * nr; nframes -= nr; lba += nr; I'm wondering if it would make sense to wrap this branch in unlikely() since it should rarely fail...? I should also mention that I've only compile tested this so far. -- Jesper Juhl - To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/