From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 117F814AD2B; Fri, 1 Aug 2025 21:26:18 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1754083579; cv=none; b=p6K93vLVvThZiMzjKWJywg5HVKlcoqhYimc2OusXXzxHN9MDOFXg3fo9izv/De45bD8z5UgLTeCDqoRE5z6SsAHYIaCZcZU8TFZ/mVVWjaygm/1EQj7wOFis5M30fRg+e/kq9SEScZnpvk3QCth+B3YbKtoWFlBegh/fYNYgbu4= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1754083579; c=relaxed/simple; bh=f4b9XfkA3nNYriclhoabu7l9n3q5dohUeAnWJVMju7Y=; h=From:To:Cc:Subject:Date:Message-ID:MIME-Version; b=Bs9TcNABMJnkMC/7+hO/RKTAyjNV/EdKaSMnfruFS81MFTB4wGIlUuJqORHUswDhtYMrc48xKzP0cpT7yUWpxc4gBtmn4QCXuK4oWUcCs2NpsfNBUbjtme9QoS3DrJGDqn2rEC4H3xOqib8uxwqRXNwAVB5P3Vm0AtjCBzP7zAM= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=PMG8srM3; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="PMG8srM3" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 4D238C4CEE7; Fri, 1 Aug 2025 21:26:18 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1754083578; bh=f4b9XfkA3nNYriclhoabu7l9n3q5dohUeAnWJVMju7Y=; h=From:To:Cc:Subject:Date:From; b=PMG8srM364lN4emJ3qvQpxqV+4ACvg5A7le4FrKzBNOaJt8fiQo1JA6rbBGVC3xj2 Ys3M83cQ8llW0FSW4EtdvUvUJD8F7bIr9FB4NeELwNl+7zHfIQ38wjqnRfEgWJOdQr Di9OzrOJJ5SS6evzfiTyuDPPwnogO48oEwoBQPhag0Ms3U+NXlUiq/6OHaBVvq3pR4 5Fkn2K1cWtQTmpw8+HEeXZIbLIYwtUeCRSNrlcVBFqPWHKIjDCGLyM/wdDirDaSeIu Tj7xtAvTySiUe+kPrEkBHIM6NG789CDLCjX46dnb7uGlJ+rlpAtvr29pX5HzCymtvt 5HuMiACNvlC6Q== From: Eric Biggers To: Peter Huewe , Jarkko Sakkinen , linux-integrity@vger.kernel.org Cc: Jason Gunthorpe , James Bottomley , linux-crypto@vger.kernel.org, linux-kernel@vger.kernel.org, Eric Biggers Subject: [PATCH v2 0/2] tpm: Clean up HMAC validation and computation Date: Fri, 1 Aug 2025 14:24:20 -0700 Message-ID: <20250801212422.9590-1-ebiggers@kernel.org> X-Mailer: git-send-email 2.50.1 Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Patch 1 updates the tpm driver to compare HMAC values in constant time. Patch 2 simplifies the HMAC computation in the tpm driver by using the library API instead of an open-coded HMAC implementation. Note that this depends on the HMAC library API that was merged for v6.17-rc1. Changed in v2: - Updated commit message of patch 1 to no longer characterize it as a fix. Explained why the side channel seems to have been benign. Eric Biggers (2): tpm: Compare HMAC values in constant time tpm: Use HMAC-SHA256 library instead of open-coded HMAC drivers/char/tpm/Kconfig | 1 + drivers/char/tpm/tpm2-sessions.c | 104 +++++++++---------------------- 2 files changed, 31 insertions(+), 74 deletions(-) base-commit: d6084bb815c453de27af8071a23163a711586a6c -- 2.50.1