linux-kernel - [PATCH AUTOSEL 3.18 23/41] ALSA: PCM: check if ops are defined before suspending PCM

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [day] [month] [year] [list]

Message-Id: <20190327182518.19394-23-sashal@kernel.org>
Date:   Wed, 27 Mar 2019 14:25:00 -0400
From:   Sasha Levin <sashal@...nel.org>
To:     linux-kernel@...r.kernel.org, stable@...r.kernel.org
Cc:     Ranjani Sridharan <ranjani.sridharan@...ux.intel.com>,
        Pierre-Louis Bossart <pierre-louis.bossart@...ux.intel.com>,
        Takashi Iwai <tiwai@...e.de>, Sasha Levin <sashal@...nel.org>
Subject: [PATCH AUTOSEL 3.18 23/41] ALSA: PCM: check if ops are defined before suspending PCM

From: Ranjani Sridharan <ranjani.sridharan@...ux.intel.com>

[ Upstream commit d9c0b2afe820fa3b3f8258a659daee2cc71ca3ef ]

BE dai links only have internal PCM's and their substream ops may
not be set. Suspending these PCM's will result in their
 ops->trigger() being invoked and cause a kernel oops.
So skip suspending PCM's if their ops are NULL.

[ NOTE: this change is required now for following the recent PCM core
  change to get rid of snd_pcm_suspend() call.  Since DPCM BE takes
  the runtime carried from FE while keeping NULL ops, it can hit this
  bug.  See details at:
     https://github.com/thesofproject/linux/pull/582
  -- tiwai ]

Signed-off-by: Ranjani Sridharan <ranjani.sridharan@...ux.intel.com>
Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@...ux.intel.com>
Signed-off-by: Takashi Iwai <tiwai@...e.de>
Signed-off-by: Sasha Levin <sashal@...nel.org>
---
 sound/core/pcm_native.c | 8 ++++++++
 1 file changed, 8 insertions(+)

diff --git a/sound/core/pcm_native.c b/sound/core/pcm_native.c
index afdb678cc757..14ea26291733 100644
--- a/sound/core/pcm_native.c
+++ b/sound/core/pcm_native.c
@@ -1308,6 +1308,14 @@ int snd_pcm_suspend_all(struct snd_pcm *pcm)
 			/* FIXME: the open/close code should lock this as well */
 			if (substream->runtime == NULL)
 				continue;
+
+			/*
+			 * Skip BE dai link PCM's that are internal and may
+			 * not have their substream ops set.
+			 */
+			if (!substream->ops)
+				continue;
+
 			err = snd_pcm_suspend(substream);
 			if (err < 0 && err != -EBUSY)
 				return err;
-- 
2.19.1