Re: [PATCH] crypto: AF_ALG - fix race accessing cipher request

From: Herbert Xu
Date: Mon Dec 11 2017 - 06:53:05 EST


On Fri, Dec 08, 2017 at 11:50:37AM +0100, Stephan Müller wrote:
> Hi Herbert,
>
> This patch would go on top of 7d2c3f54e6f646887d019faa45f35d6fe9fe82ce
> "crypto: af_alg - remove locking in async callback" found in Linus' tree
> which is not yet in the cryptodev-2.6 tree.
>
> In addition, this patch is already on top of the other patches discussed
> on this list fixing similar issues. I.e. depending in which order you apply
> the patches, there may be a hunk. In case you want me to rebase the patch,
> please let me know.
>
> ---8<---
> When invoking an asynchronous cipher operation, the invocation of the
> callback may be performed before the subsequent operations in the
> initial code path are invoked. The callback deletes the cipher request
> data structure which implies that after the invocation of the
> asynchronous cipher operation, this data structure must not be accessed
> any more.
>
> The setting of the return code size with the request data structure must
> therefore be moved before the invocation of the asynchronous cipher
> operation.
>
> Fixes: e870456d8e7c ("crypto: algif_skcipher - overhaul memory management")
> Fixes: d887c52d6ae4 ("crypto: algif_aead - overhaul memory management")
> Reported-by: syzbot <syzkaller@xxxxxxxxxxxxxxxx>
> Cc: <stable@xxxxxxxxxxxxxxx> # v4.14+
> Signed-off-by: Stephan Mueller <smueller@xxxxxxxxxx>

Patch applied. Thanks.
--
Email: Herbert Xu <herbert@xxxxxxxxxxxxxxxxxxx>
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