diff mbox

Applied "spi: fsl-espi: avoid processing uninitalized data on error" to the spi tree

Message ID E1bzLFV-0004Wz-Ut@debutante (mailing list archive)
State Not Applicable
Headers show

Commit Message

Mark Brown Oct. 26, 2016, 10:15 a.m. UTC 
The patch

   spi: fsl-espi: avoid processing uninitalized data on error

has been applied to the spi tree at

   git://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi.git 

All being well this means that it will be integrated into the linux-next
tree (usually sometime in the next 24 hours) and sent to Linus during
the next merge window (or sooner if it is a bug fix), however if
problems are discovered then the patch may be dropped or reverted.  

You may get further e-mails resulting from automated or manual testing
and review of the tree, please engage with people reporting problems and
send followup patches addressing any issues that are reported if needed.

If any updates are required or you are submitting further changes they
should be sent as incremental updates against current git, existing
patches will not be replaced.

Please add any relevant lists and maintainers to the CCs when replying
to this mail.

Thanks,
Mark

From 5c0ba57744b1422d528f19430dd66d6803cea86f Mon Sep 17 00:00:00 2001
From: Arnd Bergmann <arnd@arndb.de>
Date: Tue, 25 Oct 2016 22:57:10 +0200
Subject: [PATCH] spi: fsl-espi: avoid processing uninitalized data on error

When we get a spurious interrupt in fsl_espi_irq, we end up
processing four uninitalized bytes of data, as shown in this
warning message:

   drivers/spi/spi-fsl-espi.c: In function 'fsl_espi_irq':
   drivers/spi/spi-fsl-espi.c:462:4: warning: 'rx_data' may be used uninitialized in this function [-Wmaybe-uninitialized]

This adds another check so we skip the data in this case.

Fixes: 6319a68011b8 ("spi/fsl-espi: avoid infinite loops on fsl_espi_cpu_irq()")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Mark Brown <broonie@kernel.org>
Cc: stable@vger.kernel.org
---
 drivers/spi/spi-fsl-espi.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

Comments

Heiner Kallweit Oct. 26, 2016, 6:11 p.m. UTC | #1 
Am 26.10.2016 um 12:15 schrieb Mark Brown:
> The patch
> 
>    spi: fsl-espi: avoid processing uninitalized data on error
> 
> has been applied to the spi tree at
> 
>    git://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi.git 
> 
> All being well this means that it will be integrated into the linux-next
> tree (usually sometime in the next 24 hours) and sent to Linus during
> the next merge window (or sooner if it is a bug fix), however if
> problems are discovered then the patch may be dropped or reverted.  
> 
> You may get further e-mails resulting from automated or manual testing
> and review of the tree, please engage with people reporting problems and
> send followup patches addressing any issues that are reported if needed.
> 
> If any updates are required or you are submitting further changes they
> should be sent as incremental updates against current git, existing
> patches will not be replaced.
> 
> Please add any relevant lists and maintainers to the CCs when replying
> to this mail.
> 
> Thanks,
> Mark
> 
>>From 5c0ba57744b1422d528f19430dd66d6803cea86f Mon Sep 17 00:00:00 2001
> From: Arnd Bergmann <arnd@arndb.de>
> Date: Tue, 25 Oct 2016 22:57:10 +0200
> Subject: [PATCH] spi: fsl-espi: avoid processing uninitalized data on error
> 
> When we get a spurious interrupt in fsl_espi_irq, we end up
> processing four uninitalized bytes of data, as shown in this
> warning message:
> 
>    drivers/spi/spi-fsl-espi.c: In function 'fsl_espi_irq':
>    drivers/spi/spi-fsl-espi.c:462:4: warning: 'rx_data' may be used uninitialized in this function [-Wmaybe-uninitialized]
> 
> This adds another check so we skip the data in this case.
> 
> Fixes: 6319a68011b8 ("spi/fsl-espi: avoid infinite loops on fsl_espi_cpu_irq()")
> Signed-off-by: Arnd Bergmann <arnd@arndb.de>
> Signed-off-by: Mark Brown <broonie@kernel.org>
> Cc: stable@vger.kernel.org
> ---
>  drivers/spi/spi-fsl-espi.c | 2 +-
>  1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/spi/spi-fsl-espi.c b/drivers/spi/spi-fsl-espi.c
> index 7451585a080e..2c175b9495f7 100644
> --- a/drivers/spi/spi-fsl-espi.c
> +++ b/drivers/spi/spi-fsl-espi.c
> @@ -458,7 +458,7 @@ static void fsl_espi_cpu_irq(struct mpc8xxx_spi *mspi, u32 events)
>  
>  		mspi->len -= rx_nr_bytes;
>  
> -		if (mspi->rx)
> +		if (rx_nr_bytes && mspi->rx)
>  			mspi->get_rx(rx_data, mspi);
>  	}
>  
> 
There seems to be a merge problem. Before the relevant code was:
(changed in recent commit "spi: fsl-espi: fix handling of word
sizes other than 8 bit")

if (mspi->rx) {
	*(u32 *)mspi->rx = rx_data;
	mspi->rx += 4;
}

Now it's:

if (rx_nr_bytes && mspi->rx) {
	mspi->get_rx(rx_data, mspi);
	mspi->rx += 4;
}

Instead it should be:

if (rx_nr_bytes && mspi->rx) {
	*(u32 *)mspi->rx = rx_data;
	mspi->rx += 4;
}

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Mark Brown Oct. 26, 2016, 9:59 p.m. UTC | #2 
On Wed, Oct 26, 2016 at 08:11:28PM +0200, Heiner Kallweit wrote:

> Instead it should be:
> 
> if (rx_nr_bytes && mspi->rx) {
> 	*(u32 *)mspi->rx = rx_data;
> 	mspi->rx += 4;
> }

Please send a patch.
diff mbox

Patch

diff --git a/drivers/spi/spi-fsl-espi.c b/drivers/spi/spi-fsl-espi.c
index 7451585a080e..2c175b9495f7 100644
--- a/drivers/spi/spi-fsl-espi.c
+++ b/drivers/spi/spi-fsl-espi.c
@@ -458,7 +458,7 @@  static void fsl_espi_cpu_irq(struct mpc8xxx_spi *mspi, u32 events)
 
 		mspi->len -= rx_nr_bytes;
 
-		if (mspi->rx)
+		if (rx_nr_bytes && mspi->rx)
 			mspi->get_rx(rx_data, mspi);
 	}