Re: [PATCH v3] crypto: ixp4xx - Fix error handling path in 'aead_perform()'

[Arnd Bergmann]

On Wed, Aug 2, 2017 at 10:40 AM, Herbert Xu  wrote:
> On Thu, Jul 20, 2017 at 09:37:10AM +0200, Arnd Bergmann wrote:
>
> Oops, looks like I introduced the bug.  Anyway, such is the danger
> of fixing compiler warnings in rarely used code.
>
> For some reason your patch is corrupted in patchwork.  Also we don't
> need to check crypt->dst as free_buf_chain is a no-op if we didn't do
> the allocation at all.  So how about this patch?

Looks good to me.

> ---8<---
> In commit 0f987e25cb8a, the source processing has been moved in front of
> the destination processing, but the error handling path has not been
> modified accordingly.
> Free resources in the correct order to avoid some leaks.
>
> Fixes: 0f987e25cb8a ("crypto: ixp4xx - Fix false lastlen uninitialised 
> warning")
> Reported-by: Christophe JAILLET 
> Signed-off-by: Herbert Xu 

Reviewed-by: Arnd Bergmann 

[PATCH v3] crypto: ixp4xx - Fix error handling path in 'aead_perform()'

[Herbert Xu]

On Thu, Jul 20, 2017 at 09:37:10AM +0200, Arnd Bergmann wrote:
>
> Thanks for spotting my mistake!
> 
> I've looked at it again and think it's unfortunately still wrong with
> your patch,
> as there is a 'goto free_buf_src' after dma_pool_alloc(), and that now needs
> to jump to free_buf_dst instead. We may also need an extra check to make
> sure we don't free an uninitialized pointer again.
> 
> Can you have a look at this version below and send whatever you find
> to be correct in the end?
> 
> Signed-off-by: Arnd Bergmann 

Oops, looks like I introduced the bug.  Anyway, such is the danger
of fixing compiler warnings in rarely used code.

For some reason your patch is corrupted in patchwork.  Also we don't
need to check crypt->dst as free_buf_chain is a no-op if we didn't do
the allocation at all.  So how about this patch?

---8<---
In commit 0f987e25cb8a, the source processing has been moved in front of
the destination processing, but the error handling path has not been
modified accordingly.
Free resources in the correct order to avoid some leaks.

Fixes: 0f987e25cb8a ("crypto: ixp4xx - Fix false lastlen uninitialised warning")
Reported-by: Christophe JAILLET 
Signed-off-by: Herbert Xu 

diff --git a/drivers/crypto/ixp4xx_crypto.c b/drivers/crypto/ixp4xx_crypto.c
index 427cbe0..55dc9c2 100644
--- a/drivers/crypto/ixp4xx_crypto.c
+++ b/drivers/crypto/ixp4xx_crypto.c
@@ -1073,7 +1073,7 @@ static int aead_perform(struct aead_request *req, int 
encrypt,
req_ctx->hmac_virt = dma_pool_alloc(buffer_pool, flags,
>icv_rev_aes);
if (unlikely(!req_ctx->hmac_virt))
-   goto free_buf_src;
+   goto free_buf_dst;
if (!encrypt) {
scatterwalk_map_and_copy(req_ctx->hmac_virt,
req->src, cryptlen, authsize, 0);
@@ -1088,10 +1088,10 @@ static int aead_perform(struct aead_request *req, int 
encrypt,
BUG_ON(qmgr_stat_overflow(SEND_QID));
return -EINPROGRESS;
 
-free_buf_src:
-   free_buf_chain(dev, req_ctx->src, crypt->src_buf);
 free_buf_dst:
free_buf_chain(dev, req_ctx->dst, crypt->dst_buf);
+free_buf_src:
+   free_buf_chain(dev, req_ctx->src, crypt->src_buf);
crypt->ctl_flags = CTL_FLAG_UNUSED;
return -ENOMEM;
 }
-- 
Email: Herbert Xu 
Home Page: http://gondor.apana.org.au/~herbert/
PGP Key: http://gondor.apana.org.au/~herbert/pubkey.txt