[PATCH] ALSA: firewire-lib: fix wrong value as length of header for CIP_NO_HEADER case

[PATCH] ALSA: firewire-lib: fix wrong value as length of header for CIP_NO_HEADER case

[Takashi Sakamoto]

In a commit 1d717123bb1a ("ALSA: firewire-lib: Avoid
-Wflex-array-member-not-at-end warning"), DEFINE_FLEX() macro was used to
handle variable length of array for header field in struct fw_iso_packet
structure. The usage of macro has a side effect that the designated
initializer assigns the count of array to the given field. Therefore
CIP_HEADER_QUADLETS (=2) is assigned to struct fw_iso_packet.header,
while the original designated initializer assigns zero to all fields.

With CIP_NO_HEADER flag, the change causes invalid length of header in
isochronous packet for 1394 OHCI IT context. This bug affects all of
devices supported by ALSA fireface driver; RME Fireface 400, 800, UCX, UFX,
and 802.

This commit fixes the bug by replacing it with the alternative version of
macro which corresponds no initializer.

Cc: <stable@vger.kernel.org>
Fixes: 1d717123bb1a ("ALSA: firewire-lib: Avoid -Wflex-array-member-not-at-end warning")
Reported-by: Edmund Raile <edmund.raile@proton.me>
Closes: https://lore.kernel.org/r/rrufondjeynlkx2lniot26ablsltnynfaq2gnqvbiso7ds32il@qk4r6xps7jh2/
Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>
---
 sound/firewire/amdtp-stream.c | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/sound/firewire/amdtp-stream.c b/sound/firewire/amdtp-stream.c
index d35d0a420ee0..1a163bbcabd7 100644
--- a/sound/firewire/amdtp-stream.c
+++ b/sound/firewire/amdtp-stream.c
@@ -1180,8 +1180,7 @@ static void process_rx_packets(struct fw_iso_context *context, u32 tstamp, size_
 		(void)fw_card_read_cycle_time(fw_parent_device(s->unit)->card, &curr_cycle_time);
 
 	for (i = 0; i < packets; ++i) {
-		DEFINE_FLEX(struct fw_iso_packet, template, header,
-			    header_length, CIP_HEADER_QUADLETS);
+		DEFINE_RAW_FLEX(struct fw_iso_packet, template, header, CIP_HEADER_QUADLETS);
 		bool sched_irq = false;
 
 		build_it_pkt_header(s, desc->cycle, template, pkt_header_length,
-- 
2.43.0

Re: [PATCH] ALSA: firewire-lib: fix wrong value as length of header for CIP_NO_HEADER case

[Takashi Iwai]

On Thu, 25 Jul 2024 17:56:40 +0200,
Takashi Sakamoto wrote:
> 
> In a commit 1d717123bb1a ("ALSA: firewire-lib: Avoid
> -Wflex-array-member-not-at-end warning"), DEFINE_FLEX() macro was used to
> handle variable length of array for header field in struct fw_iso_packet
> structure. The usage of macro has a side effect that the designated
> initializer assigns the count of array to the given field. Therefore
> CIP_HEADER_QUADLETS (=2) is assigned to struct fw_iso_packet.header,
> while the original designated initializer assigns zero to all fields.
> 
> With CIP_NO_HEADER flag, the change causes invalid length of header in
> isochronous packet for 1394 OHCI IT context. This bug affects all of
> devices supported by ALSA fireface driver; RME Fireface 400, 800, UCX, UFX,
> and 802.
> 
> This commit fixes the bug by replacing it with the alternative version of
> macro which corresponds no initializer.
> 
> Cc: <stable@vger.kernel.org>
> Fixes: 1d717123bb1a ("ALSA: firewire-lib: Avoid -Wflex-array-member-not-at-end warning")
> Reported-by: Edmund Raile <edmund.raile@proton.me>
> Closes: https://lore.kernel.org/r/rrufondjeynlkx2lniot26ablsltnynfaq2gnqvbiso7ds32il@qk4r6xps7jh2/
> Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>

Thanks, applied now.


Takashi

Re: [PATCH] ALSA: firewire-lib: fix wrong value as length of header for CIP_NO_HEADER case

[Gustavo A. R. Silva]

On 25/07/24 09:56, Takashi Sakamoto wrote:
> In a commit 1d717123bb1a ("ALSA: firewire-lib: Avoid
> -Wflex-array-member-not-at-end warning"), DEFINE_FLEX() macro was used to
> handle variable length of array for header field in struct fw_iso_packet
> structure. The usage of macro has a side effect that the designated
> initializer assigns the count of array to the given field. Therefore
> CIP_HEADER_QUADLETS (=2) is assigned to struct fw_iso_packet.header,
> while the original designated initializer assigns zero to all fields.
> 
> With CIP_NO_HEADER flag, the change causes invalid length of header in
> isochronous packet for 1394 OHCI IT context. This bug affects all of
> devices supported by ALSA fireface driver; RME Fireface 400, 800, UCX, UFX,
> and 802.
> 
> This commit fixes the bug by replacing it with the alternative version of
> macro which corresponds no initializer.

This change is incomplete. The patch I mention here[1] should also be applied.

BTW, there is one more line that should probably be changed in `struct fw_iso_packet`
to avoid further confusions:

-       u16 payload_length;     /* Length of indirect payload           */
+       u16 payload_length;     /* Size of indirect payload             */

Thanks
--
Gustavo

[1] https://lore.kernel.org/linux-sound/dabb394e-6c85-45a0-bc06-7a45262a9a8c@embeddedor.com/T/#m0b9b0e7dd4561dc58422cf15df2dbd2ddb44b54b

> 
> Cc: <stable@vger.kernel.org>
> Fixes: 1d717123bb1a ("ALSA: firewire-lib: Avoid -Wflex-array-member-not-at-end warning")
> Reported-by: Edmund Raile <edmund.raile@proton.me>
> Closes: https://lore.kernel.org/r/rrufondjeynlkx2lniot26ablsltnynfaq2gnqvbiso7ds32il@qk4r6xps7jh2/
> Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>
> ---
>   sound/firewire/amdtp-stream.c | 3 +--
>   1 file changed, 1 insertion(+), 2 deletions(-)
> 
> diff --git a/sound/firewire/amdtp-stream.c b/sound/firewire/amdtp-stream.c
> index d35d0a420ee0..1a163bbcabd7 100644
> --- a/sound/firewire/amdtp-stream.c
> +++ b/sound/firewire/amdtp-stream.c
> @@ -1180,8 +1180,7 @@ static void process_rx_packets(struct fw_iso_context *context, u32 tstamp, size_
>   		(void)fw_card_read_cycle_time(fw_parent_device(s->unit)->card, &curr_cycle_time);
>   
>   	for (i = 0; i < packets; ++i) {
> -		DEFINE_FLEX(struct fw_iso_packet, template, header,
> -			    header_length, CIP_HEADER_QUADLETS);
> +		DEFINE_RAW_FLEX(struct fw_iso_packet, template, header, CIP_HEADER_QUADLETS);
>   		bool sched_irq = false;
>   
>   		build_it_pkt_header(s, desc->cycle, template, pkt_header_length,

Re: [PATCH] ALSA: firewire-lib: fix wrong value as length of header for CIP_NO_HEADER case

[Takashi Iwai]

On Thu, 25 Jul 2024 18:08:21 +0200,
Gustavo A. R. Silva wrote:
> 
> 
> 
> On 25/07/24 09:56, Takashi Sakamoto wrote:
> > In a commit 1d717123bb1a ("ALSA: firewire-lib: Avoid
> > -Wflex-array-member-not-at-end warning"), DEFINE_FLEX() macro was used to
> > handle variable length of array for header field in struct fw_iso_packet
> > structure. The usage of macro has a side effect that the designated
> > initializer assigns the count of array to the given field. Therefore
> > CIP_HEADER_QUADLETS (=2) is assigned to struct fw_iso_packet.header,
> > while the original designated initializer assigns zero to all fields.
> > 
> > With CIP_NO_HEADER flag, the change causes invalid length of header in
> > isochronous packet for 1394 OHCI IT context. This bug affects all of
> > devices supported by ALSA fireface driver; RME Fireface 400, 800, UCX, UFX,
> > and 802.
> > 
> > This commit fixes the bug by replacing it with the alternative version of
> > macro which corresponds no initializer.
> 
> This change is incomplete. The patch I mention here[1] should also be applied.

Yes, but this can be fixed by another patch, right?
At least the regression introduced by the given commit can be fixed by
that.  The other fix can go through Sakamoto-san's firewire tree
individually.


thanks,

Takashi

> BTW, there is one more line that should probably be changed in `struct fw_iso_packet`
> to avoid further confusions:
> 
> -       u16 payload_length;     /* Length of indirect payload           */
> +       u16 payload_length;     /* Size of indirect payload             */
> 
> Thanks
> --
> Gustavo
> 
> [1] https://lore.kernel.org/linux-sound/dabb394e-6c85-45a0-bc06-7a45262a9a8c@embeddedor.com/T/#m0b9b0e7dd4561dc58422cf15df2dbd2ddb44b54b
> 
> > 
> > Cc: <stable@vger.kernel.org>
> > Fixes: 1d717123bb1a ("ALSA: firewire-lib: Avoid -Wflex-array-member-not-at-end warning")
> > Reported-by: Edmund Raile <edmund.raile@proton.me>
> > Closes: https://lore.kernel.org/r/rrufondjeynlkx2lniot26ablsltnynfaq2gnqvbiso7ds32il@qk4r6xps7jh2/
> > Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>
> > ---
> >   sound/firewire/amdtp-stream.c | 3 +--
> >   1 file changed, 1 insertion(+), 2 deletions(-)
> > 
> > diff --git a/sound/firewire/amdtp-stream.c b/sound/firewire/amdtp-stream.c
> > index d35d0a420ee0..1a163bbcabd7 100644
> > --- a/sound/firewire/amdtp-stream.c
> > +++ b/sound/firewire/amdtp-stream.c
> > @@ -1180,8 +1180,7 @@ static void process_rx_packets(struct fw_iso_context *context, u32 tstamp, size_
> >   		(void)fw_card_read_cycle_time(fw_parent_device(s->unit)->card, &curr_cycle_time);
> >     	for (i = 0; i < packets; ++i) {
> > -		DEFINE_FLEX(struct fw_iso_packet, template, header,
> > -			    header_length, CIP_HEADER_QUADLETS);
> > +		DEFINE_RAW_FLEX(struct fw_iso_packet, template, header, CIP_HEADER_QUADLETS);
> >   		bool sched_irq = false;
> >     		build_it_pkt_header(s, desc->cycle, template,
> > pkt_header_length,

Re: [PATCH] ALSA: firewire-lib: fix wrong value as length of header for CIP_NO_HEADER case

[Gustavo A. R. Silva]

On 25/07/24 10:11, Takashi Iwai wrote:
> On Thu, 25 Jul 2024 18:08:21 +0200,
> Gustavo A. R. Silva wrote:
>>
>>
>>
>> On 25/07/24 09:56, Takashi Sakamoto wrote:
>>> In a commit 1d717123bb1a ("ALSA: firewire-lib: Avoid
>>> -Wflex-array-member-not-at-end warning"), DEFINE_FLEX() macro was used to
>>> handle variable length of array for header field in struct fw_iso_packet
>>> structure. The usage of macro has a side effect that the designated
>>> initializer assigns the count of array to the given field. Therefore
>>> CIP_HEADER_QUADLETS (=2) is assigned to struct fw_iso_packet.header,
>>> while the original designated initializer assigns zero to all fields.
>>>
>>> With CIP_NO_HEADER flag, the change causes invalid length of header in
>>> isochronous packet for 1394 OHCI IT context. This bug affects all of
>>> devices supported by ALSA fireface driver; RME Fireface 400, 800, UCX, UFX,
>>> and 802.
>>>
>>> This commit fixes the bug by replacing it with the alternative version of
>>> macro which corresponds no initializer.
>>
>> This change is incomplete. The patch I mention here[1] should also be applied.
> 
> Yes, but this can be fixed by another patch, right?

Yes, but why have two separate patches when the root cause can be addressed by
a single one, which will prevent other potential issues from occurring?

The main issue in this case is the __counted_by() annotation. The DEFINE_FLEX()
bug was a consequence.

--
Gustavo

> At least the regression introduced by the given commit can be fixed by
> that.  The other fix can go through Sakamoto-san's firewire tree
> individually.
> 
> 
> thanks,
> 
> Takashi
> 
>> BTW, there is one more line that should probably be changed in `struct fw_iso_packet`
>> to avoid further confusions:
>>
>> -       u16 payload_length;     /* Length of indirect payload           */
>> +       u16 payload_length;     /* Size of indirect payload             */
>>
>> Thanks
>> --
>> Gustavo
>>
>> [1] https://lore.kernel.org/linux-sound/dabb394e-6c85-45a0-bc06-7a45262a9a8c@embeddedor.com/T/#m0b9b0e7dd4561dc58422cf15df2dbd2ddb44b54b
>>
>>>
>>> Cc: <stable@vger.kernel.org>
>>> Fixes: 1d717123bb1a ("ALSA: firewire-lib: Avoid -Wflex-array-member-not-at-end warning")
>>> Reported-by: Edmund Raile <edmund.raile@proton.me>
>>> Closes: https://lore.kernel.org/r/rrufondjeynlkx2lniot26ablsltnynfaq2gnqvbiso7ds32il@qk4r6xps7jh2/
>>> Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>
>>> ---
>>>    sound/firewire/amdtp-stream.c | 3 +--
>>>    1 file changed, 1 insertion(+), 2 deletions(-)
>>>
>>> diff --git a/sound/firewire/amdtp-stream.c b/sound/firewire/amdtp-stream.c
>>> index d35d0a420ee0..1a163bbcabd7 100644
>>> --- a/sound/firewire/amdtp-stream.c
>>> +++ b/sound/firewire/amdtp-stream.c
>>> @@ -1180,8 +1180,7 @@ static void process_rx_packets(struct fw_iso_context *context, u32 tstamp, size_
>>>    		(void)fw_card_read_cycle_time(fw_parent_device(s->unit)->card, &curr_cycle_time);
>>>      	for (i = 0; i < packets; ++i) {
>>> -		DEFINE_FLEX(struct fw_iso_packet, template, header,
>>> -			    header_length, CIP_HEADER_QUADLETS);
>>> +		DEFINE_RAW_FLEX(struct fw_iso_packet, template, header, CIP_HEADER_QUADLETS);
>>>    		bool sched_irq = false;
>>>      		build_it_pkt_header(s, desc->cycle, template,
>>> pkt_header_length,

Re: [PATCH] ALSA: firewire-lib: fix wrong value as length of header for CIP_NO_HEADER case

[Takashi Sakamoto]

Hi,

On Thu, Jul 25, 2024 at 10:16:36AM -0600, Gustavo A. R. Silva wrote:
> Yes, but why have two separate patches when the root cause can be addressed by
> a single one, which will prevent other potential issues from occurring?
> 
> The main issue in this case is the __counted_by() annotation. The DEFINE_FLEX()
> bug was a consequence.

Just now I sent a patch to revert the issued commit[1].

I guess that we need the association between the two fixes. For example,
we can append more 'Fixes' tag to the patch in sound subsystem into the
patch in firewire subsystem (or vice versa).

... But it is midnight in JST, let me go to bed...


[1] https://lore.kernel.org/lkml/20240725161648.130404-1-o-takashi@sakamocchi.jp/T/#u

Thanks

Takashi Sakamoto

Re: [PATCH] ALSA: firewire-lib: fix wrong value as length of header for CIP_NO_HEADER case

[Takashi Iwai]

On Thu, 25 Jul 2024 18:25:37 +0200,
Takashi Sakamoto wrote:
> 
> Hi,
> 
> On Thu, Jul 25, 2024 at 10:16:36AM -0600, Gustavo A. R. Silva wrote:
> > Yes, but why have two separate patches when the root cause can be addressed by
> > a single one, which will prevent other potential issues from occurring?
> > 
> > The main issue in this case is the __counted_by() annotation. The DEFINE_FLEX()
> > bug was a consequence.
> 
> Just now I sent a patch to revert the issued commit[1].
> 
> I guess that we need the association between the two fixes. For example,
> we can append more 'Fixes' tag to the patch in sound subsystem into the
> patch in firewire subsystem (or vice versa).

OK, then I drop your patch for the sound stuff, and you can take it
through firewire tree.

Feel free to take my ack:
Reviewed-by: Takashi Iwai <tiwai@suse.de>


thanks,

Takashi

Re: [PATCH] ALSA: firewire-lib: fix wrong value as length of header for CIP_NO_HEADER case

[Takashi Sakamoto]

Hi,

On Thu, Jul 25, 2024 at 07:52:32PM +0200, Takashi Iwai wrote:
> On Thu, 25 Jul 2024 18:25:37 +0200,
> Takashi Sakamoto wrote:
> > 
> > Hi,
> > 
> > On Thu, Jul 25, 2024 at 10:16:36AM -0600, Gustavo A. R. Silva wrote:
> > > Yes, but why have two separate patches when the root cause can be addressed by
> > > a single one, which will prevent other potential issues from occurring?
> > > 
> > > The main issue in this case is the __counted_by() annotation. The DEFINE_FLEX()
> > > bug was a consequence.
> > 
> > Just now I sent a patch to revert the issued commit[1].
> > 
> > I guess that we need the association between the two fixes. For example,
> > we can append more 'Fixes' tag to the patch in sound subsystem into the
> > patch in firewire subsystem (or vice versa).
> 
> OK, then I drop your patch for the sound stuff, and you can take it
> through firewire tree.
> 
> Feel free to take my ack:
> Reviewed-by: Takashi Iwai <tiwai@suse.de>
 
Okay. I'll send them to mainline as fixes for v6.11-rc1.
 
> thanks,
> 
> Takashi


Thanks

Takashi Sakamoto

Re: [PATCH] ALSA: firewire-lib: fix wrong value as length of header for CIP_NO_HEADER case

[Takashi Sakamoto]

On 25/07/24 09:56, Takashi Sakamoto wrote:
> In a commit 1d717123bb1a ("ALSA: firewire-lib: Avoid
> -Wflex-array-member-not-at-end warning"), DEFINE_FLEX() macro was used to
> handle variable length of array for header field in struct fw_iso_packet
> structure. The usage of macro has a side effect that the designated
> initializer assigns the count of array to the given field. Therefore
> CIP_HEADER_QUADLETS (=2) is assigned to struct fw_iso_packet.header,
> while the original designated initializer assigns zero to all fields.
> 
> With CIP_NO_HEADER flag, the change causes invalid length of header in
> isochronous packet for 1394 OHCI IT context. This bug affects all of
> devices supported by ALSA fireface driver; RME Fireface 400, 800, UCX, UFX,
> and 802.
> 
> This commit fixes the bug by replacing it with the alternative version of
> macro which corresponds no initializer.
> 
> Cc: <stable@vger.kernel.org>
> Fixes: 1d717123bb1a ("ALSA: firewire-lib: Avoid -Wflex-array-member-not-at-end warning")
> Reported-by: Edmund Raile <edmund.raile@proton.me>
> Closes: https://lore.kernel.org/r/rrufondjeynlkx2lniot26ablsltnynfaq2gnqvbiso7ds32il@qk4r6xps7jh2/
> Signed-off-by: Takashi Sakamoto <o-takashi@sakamocchi.jp>
> ---
>   sound/firewire/amdtp-stream.c | 3 +--
>   1 file changed, 1 insertion(+), 2 deletions(-)
> 
> diff --git a/sound/firewire/amdtp-stream.c b/sound/firewire/amdtp-stream.c
> index d35d0a420ee0..1a163bbcabd7 100644
> --- a/sound/firewire/amdtp-stream.c
> +++ b/sound/firewire/amdtp-stream.c
> @@ -1180,8 +1180,7 @@ static void process_rx_packets(struct fw_iso_context *context, u32 tstamp, size_
>   		(void)fw_card_read_cycle_time(fw_parent_device(s->unit)->card, &curr_cycle_time);
>   	for (i = 0; i < packets; ++i) {
> -		DEFINE_FLEX(struct fw_iso_packet, template, header,
> -			    header_length, CIP_HEADER_QUADLETS);
> +		DEFINE_RAW_FLEX(struct fw_iso_packet, template, header, CIP_HEADER_QUADLETS);
>   		bool sched_irq = false;
>   		build_it_pkt_header(s, desc->cycle, template, pkt_header_length,

Applied to for-linus branch in firewire subsystem tree[1], and would be
sent to mainline today with another patch[2].


[1] https://git.kernel.org/pub/scm/linux/kernel/git/ieee1394/linux1394.git/log/?h=for-linus
[2] https://lore.kernel.org/lkml/20240725161648.130404-1-o-takashi@sakamocchi.jp/

Regards

Takashi Sakamoto