Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757099AbbFPJhT (ORCPT ); Tue, 16 Jun 2015 05:37:19 -0400 Received: from mail.kernel.org ([198.145.29.136]:54186 "EHLO mail.kernel.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756469AbbFPIjI (ORCPT ); Tue, 16 Jun 2015 04:39:08 -0400 From: lizf@kernel.org To: stable@vger.kernel.org Cc: linux-kernel@vger.kernel.org, Dan Carpenter , Takashi Iwai , Zefan Li Subject: [PATCH 3.4 023/172] ALSA: off by one bug in snd_riptide_joystick_probe() Date: Tue, 16 Jun 2015 16:34:37 +0800 Message-Id: <1434443826-4929-23-git-send-email-lizf@kernel.org> X-Mailer: git-send-email 1.9.1 In-Reply-To: <1434443587-4599-1-git-send-email-lizf@kernel.org> References: <1434443587-4599-1-git-send-email-lizf@kernel.org> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2547 Lines: 100 From: Dan Carpenter 3.4.108-rc1 review patch. If anyone has any objections, please let me know. ------------------ commit e4940626defdf6c92da1052ad3f12741c1a28c90 upstream. The problem here is that we check: if (dev >= SNDRV_CARDS) Then we increment "dev". if (!joystick_port[dev++]) Then we use it as an offset into a array with SNDRV_CARDS elements. if (!request_region(joystick_port[dev], 8, "Riptide gameport")) { This has 3 effects: 1) If you use the module option to specify the joystick port then it has to be shifted one space over. 2) The wrong error message will be printed on failure if you have over 32 cards. 3) Static checkers will correctly complain that are off by one. Fixes: db1005ec6ff8 ('ALSA: riptide - Fix joystick resource handling') Signed-off-by: Dan Carpenter Signed-off-by: Takashi Iwai Signed-off-by: Zefan Li --- sound/pci/riptide/riptide.c | 27 +++++++++++++++++++-------- 1 file changed, 19 insertions(+), 8 deletions(-) diff --git a/sound/pci/riptide/riptide.c b/sound/pci/riptide/riptide.c index 0481d94..c1cdd02 100644 --- a/sound/pci/riptide/riptide.c +++ b/sound/pci/riptide/riptide.c @@ -2026,32 +2026,43 @@ snd_riptide_joystick_probe(struct pci_dev *pci, const struct pci_device_id *id) { static int dev; struct gameport *gameport; + int ret; if (dev >= SNDRV_CARDS) return -ENODEV; + if (!enable[dev]) { - dev++; - return -ENOENT; + ret = -ENOENT; + goto inc_dev; } - if (!joystick_port[dev++]) - return 0; + if (!joystick_port[dev]) { + ret = 0; + goto inc_dev; + } gameport = gameport_allocate_port(); - if (!gameport) - return -ENOMEM; + if (!gameport) { + ret = -ENOMEM; + goto inc_dev; + } if (!request_region(joystick_port[dev], 8, "Riptide gameport")) { snd_printk(KERN_WARNING "Riptide: cannot grab gameport 0x%x\n", joystick_port[dev]); gameport_free_port(gameport); - return -EBUSY; + ret = -EBUSY; + goto inc_dev; } gameport->io = joystick_port[dev]; gameport_register_port(gameport); pci_set_drvdata(pci, gameport); - return 0; + + ret = 0; +inc_dev: + dev++; + return ret; } static void __devexit snd_riptide_joystick_remove(struct pci_dev *pci) -- 1.9.1 -- 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/