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From: Stephan =?ISO-8859-1?Q?M=FCller?= <smueller@chronox.de>
To: Herbert Xu <herbert@gondor.apana.org.au>
Cc: Eric Biggers <ebiggers3@gmail.com>,
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Subject: Re: [PATCH v2] crypto: AF_ALG - race-free access of encryption flag
Date: Wed, 29 Nov 2017 12:05:13 +0100
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Am Mittwoch, 29. November 2017, 08:10:49 CET schrieb Herbert Xu:

Hi Herbert,

> 
> It sort of worked for skcipher because it didn't care if ctx->enc
> or even ctx->iv changed midstream.  But even there I don't think
> we need to wait a second time.  In fact waiting a second time could
> result in a dead-lock if no sendmsg call came around.

Shouldn't we then create a patch for the pre-4.14 algif_skcipher code that 
moves the wait out of the while loop to the beginning of the function in 
recvmsg?

Ciao
Stephan