On Fri, Jun 2, 2023 at 10:41 AM Roberto Sassu <roberto.sassu@xxxxxxxxxxxxxxx> wrote: > > sorry for this unusual procedure of me requesting a patch to be pulled. > I asked for several months the maintainers (David: asymmetric keys, > Jarkko: key subsystem) to pick my patch but without any luck. Hmm. The patch behind that tag looks sane to me, but this is not code I am hugely familiar with. Who is the caller that passes in the public_key_signature data on the stack to public_key_verify_signature()? This may well be the right point to move it away from the stack in order to have a valid sg-list, but even if this patch is all good, it would be nice to have the call chain documented as part of the commit message. > I signed the tag, but probably it would not matter, since my key is not > among your trusted keys. It does matter - I do pull from people even without full chains, I just end up being a lot more careful, and I still want to see the signature for any future reference... DavidH, Herbert, please comment: > https://github.com/robertosassu/linux.git tags/asym-keys-fix-for-linus-v6.4-rc5 basically public_key_verify_signature() is passed that const struct public_key_signature *sig as an argument, and currently does sg_init_table(src_sg, 2); sg_set_buf(&src_sg[0], sig->s, sig->s_size); sg_set_buf(&src_sg[1], sig->digest, sig->digest_size); on it which is *not* ok if the s->s and s->digest points to stack data that ends up not dma'able because of a virtually mapped stack. The patch re-uses the allocation it already does for the key data, and it seems sane. But again, this is not code I look at normally, so... Linus
