Re: Unaligned accesses in sha1dc

From: Andreas Schwab <schwab@suse.de>
Date: Jun 1, 2017, 09:32 UTC
Message-ID: <mvmr2z4t5ns.fsf@suse.de>
In-Reply-To: <20170601091856.r3oaddwzsndniyfa@genre.crustytoothpaste.net>

On Jun 01 2017, "brian m. carlson" <sandals@crustytoothpaste.net> wrote:

Show 23 quoted lines

> On Thu, Jun 01, 2017 at 10:28:52AM +0200, Andreas Schwab wrote:
>> The sh1dc implementation is making unaligned accesses, which will crash
>> on some architectures, others have to emulate them in software.
>> 
>> Breakpoint 4, sha1_compression_states (ihv=0x600ffffffffe7010, 
>>     m=<optimized out>, W=0x600ffffffffe70a8, states=0x600ffffffffe7328)
>>     at sha1dc/sha1.c:398
>> 398             SHA1COMPRESS_FULL_ROUND2_STEP(e, a, b, c, d, W, 21, temp);
>> (gdb) n
>> 403             SHA1COMPRESS_FULL_ROUND2_STEP(d, e, a, b, c, W, 22, temp);
>> (gdb) 
>> 408             SHA1COMPRESS_FULL_ROUND2_STEP(c, d, e, a, b, W, 23, temp);
>> (gdb) 
>> 413             SHA1COMPRESS_FULL_ROUND2_STEP(b, c, d, e, a, W, 24, temp);
>> (gdb) 
>> 418             SHA1COMPRESS_FULL_ROUND2_STEP(a, b, c, d, e, W, 25, temp);
>> (gdb) 
>> 291             SHA1COMPRESS_FULL_ROUND1_STEP_LOAD(a, b, c, d, e, m, W, 0, temp);
>> (gdb) 
>> git(21728): unaligned access to 0x600000000009f8d5, ip=0x40000000003336d0
>> 423             SHA1COMPRESS_FULL_ROUND2_STEP(e, a, b, c, d, W, 26, temp);
>
> What architecture are you seeing this on?

It doesn't matter.

Andreas.

-- 
Andreas Schwab, SUSE Labs, schwab@suse.de
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