From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1758738Ab3E1VnG (ORCPT ); Tue, 28 May 2013 17:43:06 -0400 Received: from youngberry.canonical.com ([91.189.89.112]:59508 "EHLO youngberry.canonical.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757023Ab3E1VVV (ORCPT ); Tue, 28 May 2013 17:21:21 -0400 From: Kamal Mostafa To: linux-kernel@vger.kernel.org, stable@vger.kernel.org, kernel-team@lists.ubuntu.com Cc: Wang YanQing , Takashi Iwai , Kamal Mostafa Subject: [PATCH 17/78] ALSA: HDA: Fix Oops caused by dereference NULL pointer Date: Tue, 28 May 2013 14:19:26 -0700 Message-Id: <1369776027-17859-18-git-send-email-kamal@canonical.com> X-Mailer: git-send-email 1.8.1.2 In-Reply-To: <1369776027-17859-1-git-send-email-kamal@canonical.com> References: <1369776027-17859-1-git-send-email-kamal@canonical.com> X-Extended-Stable: 3.8 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.8.13.1 -stable review patch. If anyone has any objections, please let me know. ------------------ From: Wang YanQing commit 2195b063f6609e4c6268f291683902f25eaf9aa6 upstream. The interrupt handler azx_interrupt will call azx_update_rirb, which may call snd_hda_queue_unsol_event, snd_hda_queue_unsol_event will dereference chip->bus pointer. The problem is we alloc chip->bus in azx_codec_create which will be called after we enable IRQ and enable unsolicited event in azx_probe. This will cause Oops due dereference NULL pointer. I meet it, good luck:) [Rearranged the NULL check before the tracepoint and added another NULL check of bus->workq -- tiwai] Signed-off-by: Wang YanQing Signed-off-by: Takashi Iwai Signed-off-by: Kamal Mostafa --- sound/pci/hda/hda_codec.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/sound/pci/hda/hda_codec.c b/sound/pci/hda/hda_codec.c index 622f726..f283157 100644 --- a/sound/pci/hda/hda_codec.c +++ b/sound/pci/hda/hda_codec.c @@ -617,6 +617,9 @@ int snd_hda_queue_unsol_event(struct hda_bus *bus, u32 res, u32 res_ex) struct hda_bus_unsolicited *unsol; unsigned int wp; + if (!bus || !bus->workq) + return 0; + trace_hda_unsol_event(bus, res, res_ex); unsol = bus->unsol; if (!unsol) -- 1.8.1.2