From: Dmitry Kasatkin Date: Wed, 12 Sep 2012 10:26:55 +0000 (+0300) Subject: digsig: add hash size comparision on signature verification X-Git-Url: https://git.karo-electronics.de/?a=commitdiff_plain;h=bc01637a80f5b670bd70a0279d3f93fa8de1c96d;p=linux-beck.git digsig: add hash size comparision on signature verification When pkcs_1_v1_5_decode_emsa() returns without error and hash sizes do not match, hash comparision is not done and digsig_verify_rsa() returns no error. This is a bug and this patch fixes it. The bug was introduced in v3.3 by commit b35e286a640f ("lib/digsig: pkcs_1_v1_5_decode_emsa cleanup"). Cc: stable@vger.kernel.org Signed-off-by: Dmitry Kasatkin Signed-off-by: Linus Torvalds --- diff --git a/lib/digsig.c b/lib/digsig.c index 286d558033e2..8c0e62975c88 100644 --- a/lib/digsig.c +++ b/lib/digsig.c @@ -163,9 +163,11 @@ static int digsig_verify_rsa(struct key *key, memcpy(out1 + head, p, l); err = pkcs_1_v1_5_decode_emsa(out1, len, mblen, out2, &len); + if (err) + goto err; - if (!err && len == hlen) - err = memcmp(out2, h, hlen); + if (len != hlen || memcmp(out2, h, hlen)) + err = -EINVAL; err: mpi_free(in);