Re: WARNING: suspicious RCU usage (3)

From: Eric Biggers
Date: Wed Nov 29 2017 - 00:06:15 EST


On Tue, Nov 28, 2017 at 01:30:26PM -0800, Andrew Morton wrote:
>
> It looks like blkcipher_walk_done() passed a bad address to kfree().
>

Indeed, it's freeing uninitialized memory because the Salsa20 algorithms are
using the blkcipher_walk API incorrectly. I've sent a patch to fix it:

"crypto: salsa20 - fix blkcipher_walk API usage"

I am not sure why the bug reports show up as "suspicious RCU usage", though.

There were also a few other syzbot reports of this same underlying bug; I marked
them as duplicates of this one.

Eric