Re: [syzbot] [crypto?] KMSAN: uninit-value in skcipher_walk_virt

From: Ard Biesheuvel
Date: Mon May 06 2024 - 06:52:47 EST


On Sat, 4 May 2024 at 19:21, Kent Overstreet <kent.overstreet@xxxxxxxxx> wrote:
>
> This is odd - it seems to be req->base.flags that's uninitialized, and I
> can't find the code that's supposed to be initializing it - but bcachefs
> usage seems to be the same as all the other uses I'm looking at; if it
> is req->base.flags then other code must be buggy as well?
>

You seem to be missing a call to

skcipher_request_set_callback()

which initializes some (irrelevant in this case) async related fields
but also the flags field.