diff mbox series

crypto: caam: Clear some memory in instantiate_rng()

Message ID 16d6bf3bd7a6e96a8262fcd4680e3ccbb5a50478.1679355849.git.christophe.jaillet@wanadoo.fr
State New
Headers
Series crypto: caam: Clear some memory in instantiate_rng() |

Commit Message

Christophe JAILLET March 20, 2023, 11:45 p.m. UTC 
  According to the comment at the end of the 'for' loop just a few lines
below, it looks needed to clear 'desc'.

So it should also be cleared for the first iteration.

Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
---
This patch is speculative, but can't hurt.

Maybe the memset() at the end of the 'for' loop could be removed instead.
---
 drivers/crypto/caam/ctrl.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

Comments

Herbert Xu March 21, 2023, 3:26 a.m. UTC | #1 
On Tue, Mar 21, 2023 at 12:45:43AM +0100, Christophe JAILLET wrote:
> According to the comment at the end of the 'for' loop just a few lines
> below, it looks needed to clear 'desc'.
> 
> So it should also be cleared for the first iteration.
> 
> Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
> ---
> This patch is speculative, but can't hurt.
> 
> Maybe the memset() at the end of the 'for' loop could be removed instead.

I think the memset can be removed.  Horia?
Gaurav Jain March 21, 2023, 5:03 a.m. UTC | #2 
Hi Herbert

> -----Original Message-----
> From: Herbert Xu <herbert@gondor.apana.org.au>
> Sent: Tuesday, March 21, 2023 8:57 AM
> To: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
> Cc: Horia Geanta <horia.geanta@nxp.com>; Pankaj Gupta
> <pankaj.gupta@nxp.com>; Gaurav Jain <gaurav.jain@nxp.com>;
> davem@davemloft.net; linux-crypto@vger.kernel.org; linux-
> kernel@vger.kernel.org; kernel-janitors@vger.kernel.org
> Subject: [EXT] Re: [PATCH] crypto: caam: Clear some memory in
> instantiate_rng()
> 
> Caution: EXT Email
> 
> On Tue, Mar 21, 2023 at 12:45:43AM +0100, Christophe JAILLET wrote:
> > According to the comment at the end of the 'for' loop just a few lines
> > below, it looks needed to clear 'desc'.
> >
> > So it should also be cleared for the first iteration.
> >
> > Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
> > ---
> > This patch is speculative, but can't hurt.
> >
> > Maybe the memset() at the end of the 'for' loop could be removed instead.
> 
> I think the memset can be removed.  Horia?
memset() is needed to clear the desc for each state handle before recreating descriptor.
So it is required.

Regards
Gaurav Jain
> --
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Herbert Xu March 21, 2023, 5:06 a.m. UTC | #3 
On Tue, Mar 21, 2023 at 05:03:24AM +0000, Gaurav Jain wrote:
>
> memset() is needed to clear the desc for each state handle before recreating descriptor.
> So it is required.

OK so we should move it to the top of the loop then.

Thanks,
Gaurav Jain March 21, 2023, 6:55 a.m. UTC | #4 
Hi

> -----Original Message-----
> From: Herbert Xu <herbert@gondor.apana.org.au>
> Sent: Tuesday, March 21, 2023 10:37 AM
> To: Gaurav Jain <gaurav.jain@nxp.com>
> Cc: Christophe JAILLET <christophe.jaillet@wanadoo.fr>; Horia Geanta
> <horia.geanta@nxp.com>; Pankaj Gupta <pankaj.gupta@nxp.com>;
> davem@davemloft.net; linux-crypto@vger.kernel.org; linux-
> kernel@vger.kernel.org; kernel-janitors@vger.kernel.org
> Subject: Re: [EXT] Re: [PATCH] crypto: caam: Clear some memory in
> instantiate_rng()
> 
> Caution: EXT Email
> 
> On Tue, Mar 21, 2023 at 05:03:24AM +0000, Gaurav Jain wrote:
> >
> > memset() is needed to clear the desc for each state handle before
> recreating descriptor.
> > So it is required.
> 
> OK so we should move it to the top of the loop then.
kzalloc() will zeroize the contents of desc for the first time.
In this case memset() is ok at the end for instantiating other rng handles.
 
Thanks
Gaurav

> 
> Thanks,
> --
> Email: Herbert Xu <herbert@gondor.apana.org.au> Home Page:
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diff mbox series

Patch

diff --git a/drivers/crypto/caam/ctrl.c b/drivers/crypto/caam/ctrl.c
index 32253a064d0f..e4e971dc0f96 100644
--- a/drivers/crypto/caam/ctrl.c
+++ b/drivers/crypto/caam/ctrl.c
@@ -276,7 +276,7 @@  static int instantiate_rng(struct device *ctrldev, int state_handle_mask,
 	int ret = 0, sh_idx;
 
 	ctrl = (struct caam_ctrl __iomem *)ctrlpriv->ctrl;
-	desc = kmalloc(CAAM_CMD_SZ * 7, GFP_KERNEL | GFP_DMA);
+	desc = kzalloc(CAAM_CMD_SZ * 7, GFP_KERNEL | GFP_DMA);
 	if (!desc)
 		return -ENOMEM;