Re: [patch] crypto: sha256-mb - cleanup a || vs | typo

From: Dan Carpenter
Date: Thu Jun 30 2016 - 18:17:44 EST


On Thu, Jun 30, 2016 at 01:42:19PM -0700, Tim Chen wrote:
> On Wed, 2016-06-29 at 10:05 -0700, H. Peter Anvin wrote:
> > On 06/29/16 07:42, Dan Carpenter wrote:
> > >
> > > >
> > > > >
> > > > > and | behave basically the same here but || is intended.  It causes a
> > > static checker warning to mix up bitwise and logical operations.
> > >
> > > Signed-off-by: Dan Carpenter <dan.carpenter@xxxxxxxxxx>
> > >
> > > diff --git a/arch/x86/crypto/sha256-mb/sha256_mb.c b/arch/x86/crypto/sha256-mb/sha256_mb.c
> > > index c9d5dcc..4ec895a 100644
> > > --- a/arch/x86/crypto/sha256-mb/sha256_mb.c
> > > +++ b/arch/x86/crypto/sha256-mb/sha256_mb.c
> > > @@ -299,7 +299,7 @@ static struct sha256_hash_ctx *sha256_ctx_mgr_submit(struct sha256_ctx_mgr *mgr,
> > >    * Or if the user's buffer contains less than a whole block,
> > >    * append as much as possible to the extra block.
> > >    */
> > > - if ((ctx->partial_block_buffer_length) | (len < SHA256_BLOCK_SIZE)) {
> > > + if ((ctx->partial_block_buffer_length) || (len < SHA256_BLOCK_SIZE)) {
> > >   /* Compute how many bytes to copy from user buffer into
> > >    * extra block
> > >    */
> > >
> > As far as I know the | was an intentional optimization, so you may way
> > to look at the generated code.
> >
> > -hpa
> >
>
> Yes, this is an intentional optimization.  Is there any scenario where things may
> break with the compiler?

No. I'm going to remove the warning from the static checker like I said
earlier. It should only complain for && vs & typos, || vs | is
harmless.

regards,
dan carpenter