[PATCH] ARM: u300: add missing check for kmalloc

[PATCH] ARM: u300: add missing check for kmalloc

[Nicholas Mc Guire]

 kmalloc return for bigrxbuf_virtual was not being checked - in case
of failure set status, cleanup bigtxbuf_virtual and baile out.

Signed-off-by: Nicholas Mc Guire <hofrat@osadl.org>
Fixes: c7c8c78fdf6e ("ARM: 5667/3: U300 SSP/SPI board setup and test")
---

Issue found with experimental coccinelle script

Not sure about the checkpatch message: 
CHECK: Comparison to NULL could be written "!bigrxbuf_virtual"
#32: FILE: arch/arm/mach-u300/dummyspichip.c:67:
+       if (bigrxbuf_virtual == NULL) {
As the current check for bigtxbuf_virtual uses == NULL that 
was retained for consistency here.

Patch was compile tested with: u300_defconfig (implies MACH_U300_SPIDUMMY=y)

Patch is against 4.18 (localversion-next is next-20180824)

 arch/arm/mach-u300/dummyspichip.c | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/arch/arm/mach-u300/dummyspichip.c b/arch/arm/mach-u300/dummyspichip.c
index 68fe986..ff293ee 100644
--- a/arch/arm/mach-u300/dummyspichip.c
+++ b/arch/arm/mach-u300/dummyspichip.c
@@ -62,7 +62,13 @@ static ssize_t dummy_looptest(struct device *dev,
 		status = -ENOMEM;
 		goto out;
 	}
+
 	bigrxbuf_virtual = kmalloc(DMA_TEST_SIZE, GFP_KERNEL);
+	if (bigrxbuf_virtual == NULL) {
+		kfree(bigtxbuf_virtual);
+		status = -ENOMEM;
+		goto out;
+	}
 
 	/* Fill TXBUF with some happy pattern */
 	memset(bigtxbuf_virtual, 0xAA, DMA_TEST_SIZE);
-- 
2.1.4

Re: [PATCH] ARM: u300: add missing check for kmalloc

[Linus Walleij]

On Fri, Aug 24, 2018 at 12:33 PM Nicholas Mc Guire <hofrat@osadl.org> wrote:

>  kmalloc return for bigrxbuf_virtual was not being checked - in case
> of failure set status, cleanup bigtxbuf_virtual and baile out.
>
> Signed-off-by: Nicholas Mc Guire <hofrat@osadl.org>
> Fixes: c7c8c78fdf6e ("ARM: 5667/3: U300 SSP/SPI board setup and test")

I will delete this testchip instead. It is not in use.

Yours,
Linus Walleij

Re: [PATCH] ARM: u300: add missing check for kmalloc

[Nicholas Mc Guire]

On Wed, Sep 05, 2018 at 11:09:21AM +0200, Linus Walleij wrote:
> On Fri, Aug 24, 2018 at 12:33 PM Nicholas Mc Guire <hofrat@osadl.org> wrote:
> 
> >  kmalloc return for bigrxbuf_virtual was not being checked - in case
> > of failure set status, cleanup bigtxbuf_virtual and baile out.
> >
> > Signed-off-by: Nicholas Mc Guire <hofrat@osadl.org>
> > Fixes: c7c8c78fdf6e ("ARM: 5667/3: U300 SSP/SPI board setup and test")
> 
> I will delete this testchip instead. It is not in use.
>
well that will for sure eliminate this bug reliably ;)

thx!
hofrat 

[PATCH 0/4] ARM: imx legacy: cleanups

[Nicholas Mc Guire]

While preparing a proposed fix for a missing check on zmalloc a few
other checkpatch warnings poped up - this little set fixes those
warnings. There is one remaining checkpatch warning but that looks
like a false-positive to me:

ERROR: Use of __initconst requires a separate use of const
#171: FILE: arch/arm/mach-imx/mach-mx27ads.c:171:
+mx27ads_nand_board_info __initconst = {

The false positive seems due to the definition spanning two lines
anyway looks good to me

<snip>
static const struct mxc_nand_platform_data
mx27ads_nand_board_info __initconst = {
        .width = 1,
        .hw_ecc = 1,
};
<snip>

thx!
hofrat

[PATCH] ARM: u300: add missing check for kmalloc

[Nicholas Mc Guire]

 kmalloc return for bigrxbuf_virtual was not being checked - in case
of failure set status, cleanup bigtxbuf_virtual and baile out.

Signed-off-by: Nicholas Mc Guire <hofrat@osadl.org>
Fixes: c7c8c78fdf6e ("ARM: 5667/3: U300 SSP/SPI board setup and test")
---

Issue found with experimental coccinelle script

Not sure about the checkpatch message: 
CHECK: Comparison to NULL could be written "!bigrxbuf_virtual"
#32: FILE: arch/arm/mach-u300/dummyspichip.c:67:
+       if (bigrxbuf_virtual == NULL) {
As the current check for bigtxbuf_virtual uses == NULL that 
was retained for consistency here.

Patch was compile tested with: u300_defconfig (implies MACH_U300_SPIDUMMY=y)

Patch is against 4.18 (localversion-next is next-20180824)

 arch/arm/mach-u300/dummyspichip.c | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/arch/arm/mach-u300/dummyspichip.c b/arch/arm/mach-u300/dummyspichip.c
index 68fe986..ff293ee 100644
--- a/arch/arm/mach-u300/dummyspichip.c
+++ b/arch/arm/mach-u300/dummyspichip.c
@@ -62,7 +62,13 @@ static ssize_t dummy_looptest(struct device *dev,
 		status = -ENOMEM;
 		goto out;
 	}
+
 	bigrxbuf_virtual = kmalloc(DMA_TEST_SIZE, GFP_KERNEL);
+	if (bigrxbuf_virtual == NULL) {
+		kfree(bigtxbuf_virtual);
+		status = -ENOMEM;
+		goto out;
+	}
 
 	/* Fill TXBUF with some happy pattern */
 	memset(bigtxbuf_virtual, 0xAA, DMA_TEST_SIZE);
-- 
2.1.4

Re: [PATCH] ARM: u300: add missing check for kmalloc

[Linus Walleij]

Hi Nicholas,

thanks for your patch!

On Sat, Apr 13, 2019 at 9:20 AM Nicholas Mc Guire <hofrat@osadl.org> wrote:

>  kmalloc return for bigrxbuf_virtual was not being checked - in case
> of failure set status, cleanup bigtxbuf_virtual and baile out.
>
> Signed-off-by: Nicholas Mc Guire <hofrat@osadl.org>
> Fixes: c7c8c78fdf6e ("ARM: 5667/3: U300 SSP/SPI board setup and test")

This code is deleted from the kernel and the code had
zero users before that, so no need to fix it! Sorry for your
trouble!

Yours,
Linus Walleij