Patch "ALSA: firewire: fix NULL pointer dereference when releasing uninitialized data of iso-resource" has been added to the 4.12-stable tree

Patch "ALSA: firewire: fix NULL pointer dereference when releasing uninitialized data of iso-resource" has been added to the 4.12-stable tree

[gregkh]

This is a note to let you know that I've just added the patch titled

    ALSA: firewire: fix NULL pointer dereference when releasing uninitialized data of iso-resource

to the 4.12-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     alsa-firewire-fix-null-pointer-dereference-when-releasing-uninitialized-data-of-iso-resource.patch
and it can be found in the queue-4.12 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@vger.kernel.org> know about it.


>From 0c264af7be2013266c5b4c644f3f366399ee490a Mon Sep 17 00:00:00 2001
From: Takashi Sakamoto <o-takashi@sakamocchi.jp>
Date: Sun, 20 Aug 2017 15:54:26 +0900
Subject: ALSA: firewire: fix NULL pointer dereference when releasing uninitialized data of iso-resource

From: Takashi Sakamoto <o-takashi@sakamocchi.jp>

commit 0c264af7be2013266c5b4c644f3f366399ee490a upstream.

When calling 'iso_resource_free()' for uninitialized data, this function
causes NULL pointer dereference due to its 'unit' member. This occurs when
unplugging audio and music units on IEEE 1394 bus at failure of card
registration.

This commit fixes the bug. The bug exists since kernel v4.5.

Fixes: 324540c4e05c ('ALSA: fireface: postpone sound card registration') at v4.12
Fixes: 8865a31e0fd8 ('ALSA: firewire-motu: postpone sound card registration') at v4.12
Fixes: b610386c8afb ('ALSA: firewire-tascam: deleyed registration of sound card') at v4.7
Fixes: 86c8dd7f4da3 ('ALSA: firewire-digi00x: delayed registration of sound card') at v4.7
Fixes: 6c29230e2a5f ('ALSA: oxfw: delayed registration of sound card') at v4.7
Fixes: 7d3c1d5901aa ('ALSA: fireworks: delayed registration of sound card') at v4.7
Fixes: 04a2c73c97eb ('ALSA: bebob: delayed registration of sound card') at v4.7
Fixes: b59fb1900b4f ('ALSA: dice: postpone card registration') at v4.5
Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
 sound/firewire/iso-resources.c |    7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

--- a/sound/firewire/iso-resources.c
+++ b/sound/firewire/iso-resources.c
@@ -210,9 +210,14 @@ EXPORT_SYMBOL(fw_iso_resources_update);
  */
 void fw_iso_resources_free(struct fw_iso_resources *r)
 {
-	struct fw_card *card = fw_parent_device(r->unit)->card;
+	struct fw_card *card;
 	int bandwidth, channel;
 
+	/* Not initialized. */
+	if (r->unit == NULL)
+		return;
+	card = fw_parent_device(r->unit)->card;
+
 	mutex_lock(&r->mutex);
 
 	if (r->allocated) {


Patches currently in stable-queue which might be from o-takashi@sakamocchi.jp are

queue-4.12/alsa-firewire-motu-destroy-stream-data-surely-at-failure-of-card-initialization.patch
queue-4.12/alsa-firewire-fix-null-pointer-dereference-when-releasing-uninitialized-data-of-iso-resource.patch