Re: [PATCH] dell-smbios: fix string overflow

[Arnd Bergmann]

On Wed, Nov 8, 2017 at 7:22 PM, sathyanarayanan kuppuswamy
<sathyanarayanan.kuppuswamy@xxxxxxxxxxxxxxx> wrote:
> Hi,
>
> I recommend using "platform/x86: dell-smbios:" in commit header.

Ok, noted. I usually try to follow the lines for each maintainer, but
I'm not always
keeping track of each one, sorry.

> On 11/08/2017 04:08 AM, Arnd Bergmann wrote:
>>
>> The new sysfs code overwrites two fixed-length character arrays
>> that are each one byte shorter than they need to be, to hold
>> the trailing \0:
>>
>> drivers/platform/x86/dell-smbios.c: In function 'build_tokens_sysfs':
>> drivers/platform/x86/dell-smbios.c:494:42: error: 'sprintf' writing a
>> terminating nul past the end of the destination [-Werror=format-overflow=]
>>     sprintf(buffer_location, "%04x_location",
>> drivers/platform/x86/dell-smbios.c:494:3: note: 'sprintf' output 14 bytes
>> into a destination of size 13
>> drivers/platform/x86/dell-smbios.c:506:36: error: 'sprintf' writing a
>> terminating nul past the end of the destination [-Werror=format-overflow=]
>>     sprintf(buffer_value, "%04x_value",
>> drivers/platform/x86/dell-smbios.c:506:3: note: 'sprintf' output 11 bytes
>> into a destination of size 10
>
> Don't need to include the error log in commit message. Just explaining the
> issue is good enough.

I always include the messages I get, it helps a lot when you run into a related
problem and find it in either the git log or using google search.

It's particularly useful when patches that introduce warnings get backported
to stable kernels.

      Arnd