From: Stephan =?ISO-8859-1?Q?M=FCller?= <smueller@chronox.de>
Subject: Re: BUG: Seems un-initialed dst pointer received from algif_aead when outlen is zero
Date: Tue, 21 Mar 2017 11:04:35 +0100
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Cc: linux-crypto@vger.kernel.org,
        Herbert Xu <herbert@gondor.apana.org.au>
To: Harsh Jain <harshjain.prof@gmail.com>
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Am Dienstag, 21. M?rz 2017, 07:13:53 CET schrieb Harsh Jain:

Hi Harsh,

> Hi,
> 
> For tag only AEAD decrypt operation(Zero length Payload). The dst sg
> list pointer panic with general protection fault. I think it should be
> NULL when output buffer is supposed to be empty.
> 
> Kcapi command to re-produce the issue
> 
> ./kcapi -x 2   -c "gcm(aes)" -i 0d92aa861746b324f20ee6b7 -k
> f4a6a5e5f2066f6dd9ec6fc5169c29043560ef595c9e81e76f42d29212cc581c -a ""
> -t "5f24c68cbe6f32c29652442bf5d483ad" -q ""
> 
> Its decrypt operation. Expected result should be EBADMSG.

Executing this command on a 4.9 kernel, I get:

bin/kcapi -x 2   -c "gcm(aes)" -i 0d92aa861746b324f20ee6b7 -k 
f4a6a5e5f2066f6dd9ec6fc5169c29043560ef595c9e81e76f42d29212cc581c -a "" -t 
"5f24c68cbe6f32c29652442bf5d483ad" -q ""
EBADMSG

There is no GP or other error. Can you please provide some details about your 
system? I.e. which kernel version and what cipher implementation resolves to 
gcm(aes)?

Thanks

Ciao
Stephan