Re: [PATCH v4 13/14] rxrpc: Prepare to remove VLA usage for SKCIPHER_REQUEST_ON_STACK

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



On Thu, Jul 12, 2018 at 8:11 AM, Arnd Bergmann <arnd@xxxxxxxx> wrote:
> On Wed, Jul 11, 2018 at 10:36 PM, Kees Cook <keescook@xxxxxxxxxxxx> wrote:
>> Two uses of SKCIPHER_REQUEST_ON_STACK() will trigger FRAME_WARN warnings
>> (when less than 2048) once the VLA is no longer hidden from the check:
>>
>> net/rxrpc/rxkad.c:398:1: warning: the frame size of 1152 bytes is larger than 1024 bytes [-Wframe-larger-than=]
>> net/rxrpc/rxkad.c:242:1: warning: the frame size of 1152 bytes is larger than 1024 bytes [-Wframe-larger-than=]
>>
>> This bumps the affected objects by 20% to silence the warnings while
>> still providing coverage is anything grows even more.
>>
>> Signed-off-by: Kees Cook <keescook@xxxxxxxxxxxx>
>
> (adding David Howells to cc)
>
> I don't think these are in a fast path, it should be possible to just use
> skcipher_alloc_req() instead of SKCIPHER_REQUEST_ON_STACK() here.
> From what I can tell, neither of the two are called in atomic context, so
> you should be able to use a GFP_KERNEL allocation.

Sure, I can do that instead.

-Kees

-- 
Kees Cook
Pixel Security

--
dm-devel mailing list
dm-devel@xxxxxxxxxx
https://www.redhat.com/mailman/listinfo/dm-devel



[Index of Archives]     [DM Crypt]     [Fedora Desktop]     [ATA RAID]     [Fedora Marketing]     [Fedora Packaging]     [Fedora SELinux]     [Yosemite Discussion]     [KDE Users]     [Fedora Docs]

  Powered by Linux