Re: [PATCH v2] staging: atomisp: use kstrdup to replace kmalloc and memcpy

From: hari prasath
Date: Mon Jul 10 2017 - 02:22:35 EST


On 10 July 2017 at 01:22, Sakari Ailus <sakari.ailus@xxxxxx> wrote:
> On Sun, Jul 09, 2017 at 05:56:15PM +0530, hari prasath wrote:
>> On 8 July 2017 at 16:31, Sakari Ailus <sakari.ailus@xxxxxx> wrote:
>> > Hi Hari,
>> >
>> > On Fri, Jul 07, 2017 at 08:15:21PM +0530, Hari Prasath wrote:
>> >> kstrdup kernel primitive can be used to replace kmalloc followed by
>> >> string copy. This was reported by coccinelle tool
>> >>
>> >> Signed-off-by: Hari Prasath <gehariprasath@xxxxxxxxx>
>> >> ---
>> >> .../media/atomisp/pci/atomisp2/css2400/sh_css_firmware.c | 10 +++-------
>> >> 1 file changed, 3 insertions(+), 7 deletions(-)
>> >>
>> >> diff --git a/drivers/staging/media/atomisp/pci/atomisp2/css2400/sh_css_firmware.c b/drivers/staging/media/atomisp/pci/atomisp2/css2400/sh_css_firmware.c
>> >> index 34cc56f..68db87b 100644
>> >> --- a/drivers/staging/media/atomisp/pci/atomisp2/css2400/sh_css_firmware.c
>> >> +++ b/drivers/staging/media/atomisp/pci/atomisp2/css2400/sh_css_firmware.c
>> >> @@ -144,14 +144,10 @@ sh_css_load_blob_info(const char *fw, const struct ia_css_fw_info *bi, struct ia
>> >> )
>> >> {
>> >> char *namebuffer;
>> >> - int namelength = (int)strlen(name);
>> >> -
>> >> - namebuffer = (char *) kmalloc(namelength + 1, GFP_KERNEL);
>> >> - if (namebuffer == NULL)
>> >> - return IA_CSS_ERR_CANNOT_ALLOCATE_MEMORY;
>> >> -
>> >> - memcpy(namebuffer, name, namelength + 1);
>> >>
>> >> + namebuffer = kstrdup(name, GFP_KERNEL);
>> >> + if (!namebuffer)
>> >> + return -ENOMEM;
>> >
>> > The patch also changes the return value in error cases. I believe the
>> > caller(s) expect to get errors in the IA_CCS_ERR_* range.
>>
>> Hi,
>>
>> In this particular case, the calling function just checks if it's not
>> success defined by a enum. I think returning -ENOMEM would not effect,
>> at least in this case.
>
> It might not, but the function now returns both negative Posix and positive
> CSS error codes. The CSS error codes could well be converted to Posix but
> it should be done consistently and preferrably in a separate patch.


Hi Sakari, Thanks for your comments. I will stick with just replacing
with kstrdup and retain the original error return value. I will send a
v3.

Regards,
Hari

>
> --
> Sakari Ailus
> e-mail: sakari.ailus@xxxxxx XMPP: sailus@xxxxxxxxxxxxxx



--
Regards,
G.E.Hari Prasath