From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id EECF1C433F5 for ; Tue, 12 Oct 2021 08:27:20 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id C3FEB60E74 for ; Tue, 12 Oct 2021 08:27:20 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234711AbhJLI3V (ORCPT ); Tue, 12 Oct 2021 04:29:21 -0400 Received: from smtp-out1.suse.de ([195.135.220.28]:42676 "EHLO smtp-out1.suse.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S234736AbhJLI3U (ORCPT ); Tue, 12 Oct 2021 04:29:20 -0400 Received: from imap2.suse-dmz.suse.de (imap2.suse-dmz.suse.de [192.168.254.74]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (P-521) server-digest SHA512) (No client certificate requested) by smtp-out1.suse.de (Postfix) with ESMTPS id A1BEC21F2C; Tue, 12 Oct 2021 08:27:18 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=suse.de; s=susede2_rsa; t=1634027238; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc:cc: mime-version:mime-version: content-transfer-encoding:content-transfer-encoding; bh=zD9QTV4WyXthA7N/2eYXkVzurQrRAnyA96sGjWbnf5A=; b=j5ZCZf6SyHkjCi5k0JocrOJfsP4v3eZUU9uNo1rxGQJn8ktR7Tt2ubUs0JfqtrY2iNlpec ETHMFEk73gM4gj74FUyTqsm0AipjlyOFV1YBu7fsDmm75SFH7s23MNqt5/fV47LFPBoRAC NMJvAiKQNl/6f4F6NM3dkqQ9q5C32MU= DKIM-Signature: v=1; a=ed25519-sha256; c=relaxed/relaxed; d=suse.de; s=susede2_ed25519; t=1634027238; h=from:from:reply-to:date:date:message-id:message-id:to:to:cc:cc: mime-version:mime-version: content-transfer-encoding:content-transfer-encoding; bh=zD9QTV4WyXthA7N/2eYXkVzurQrRAnyA96sGjWbnf5A=; b=aLWA8vxcED2t4X6I9/ThVRx7D02Hpg3kFw8dnxb6bTL6fDlOacqKqIzWCqFya2DaRN19y3 udvxByOy2o86mVAA== Received: from imap2.suse-dmz.suse.de (imap2.suse-dmz.suse.de [192.168.254.74]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (P-521) server-digest SHA512) (No client certificate requested) by imap2.suse-dmz.suse.de (Postfix) with ESMTPS id 8792813AD5; Tue, 12 Oct 2021 08:27:18 +0000 (UTC) Received: from dovecot-director2.suse.de ([192.168.254.65]) by imap2.suse-dmz.suse.de with ESMTPSA id uHvPIOZGZWE+SQAAMHmgww (envelope-from ); Tue, 12 Oct 2021 08:27:18 +0000 From: "Ivan T. Ivanov" To: Ard Biesheuvel Cc: Dominik Brodowski , Bhupesh Sharma , linux-efi@vger.kernel.org, linux-kernel@vger.kernel.org, "Ivan T. Ivanov" Subject: [PATCH] Revert "efi/random: Treat EFI_RNG_PROTOCOL output as bootloader randomness" Date: Tue, 12 Oct 2021 11:27:08 +0300 Message-Id: <20211012082708.121931-1-iivanov@suse.de> X-Mailer: git-send-email 2.33.0 MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Precedence: bulk List-ID: X-Mailing-List: linux-efi@vger.kernel.org This reverts commit 18b915ac6b0ac5ba7ded03156860f60a9f16df2b. When CONFIG_RANDOM_TRUST_BOOTLOADER is enabled add_bootloader_randomness() calls add_hwgenerator_randomness() which might sleep, but this is not possible during early kernel initialization. This revert fixes following NULL pointer deference: [ 0.000000] efi: seeding entropy pool [ 0.000000] Unable to handle kernel NULL pointer dereference at virtual address 0000000000000000 ... [ 0.000000] pc : kthread_should_stop+0x2c/0x60 [ 0.000000] lr : add_hwgenerator_randomness+0x58/0x178 ... [ 0.000000] Call trace: [ 0.000000] kthread_should_stop+0x2c/0x60 [ 0.000000] add_bootloader_randomness+0x2c/0x38 [ 0.000000] efi_config_parse_tables+0x120/0x250 [ 0.000000] efi_init+0x138/0x1e0 [ 0.000000] setup_arch+0x394/0x778 [ 0.000000] start_kernel+0x90/0x568 Signed-off-by: Ivan T. Ivanov --- drivers/firmware/efi/efi.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/firmware/efi/efi.c b/drivers/firmware/efi/efi.c index 847f33ffc4ae..8aad3c524947 100644 --- a/drivers/firmware/efi/efi.c +++ b/drivers/firmware/efi/efi.c @@ -600,7 +600,7 @@ int __init efi_config_parse_tables(const efi_config_table_t *config_tables, sizeof(*seed) + size); if (seed != NULL) { pr_notice("seeding entropy pool\n"); - add_bootloader_randomness(seed->bits, size); + add_device_randomness(seed->bits, size); early_memunmap(seed, sizeof(*seed) + size); } else { pr_err("Could not map UEFI random seed!\n"); -- 2.33.0