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 C18839443 for ; Sun, 13 Aug 2023 21:24:24 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 49F8AC433C8; Sun, 13 Aug 2023 21:24:24 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1691961864; bh=PDqFwxloBi56MjK1bImd8BijxMoZfbqySfjUa9RU8Mk=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=QGZ8YWKGUaUKE8ouPivTHW22ZqngofA2DTTifVCuVXS6aY7Ry1U0vgcOeQEXlkX/a DQ4GzpQL/oAF46OkedUlAZA6y+yBLvS511V7yCuXMaPfTbEIoczgV0v8ihulCzDnsF wvYqTP+23meq/EVeYPWDrL3vZUrNFfmci5h5yzLw= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Mario Limonciello , Linus Torvalds Subject: [PATCH 6.4 004/206] tpm: Add a helper for checking hwrng enabled Date: Sun, 13 Aug 2023 23:16:14 +0200 Message-ID: <20230813211725.099915890@linuxfoundation.org> X-Mailer: git-send-email 2.41.0 In-Reply-To: <20230813211724.969019629@linuxfoundation.org> References: <20230813211724.969019629@linuxfoundation.org> User-Agent: quilt/0.67 Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit From: Mario Limonciello commit cacc6e22932f373a91d7be55a9b992dc77f4c59b upstream. The same checks are repeated in three places to decide whether to use hwrng. Consolidate these into a helper. Also this fixes a case that one of them was missing a check in the cleanup path. Fixes: 554b841d4703 ("tpm: Disable RNG for all AMD fTPMs") Signed-off-by: Mario Limonciello Signed-off-by: Linus Torvalds Signed-off-by: Greg Kroah-Hartman --- drivers/char/tpm/tpm-chip.c | 19 ++++++++++++++----- 1 file changed, 14 insertions(+), 5 deletions(-) --- a/drivers/char/tpm/tpm-chip.c +++ b/drivers/char/tpm/tpm-chip.c @@ -521,10 +521,20 @@ static int tpm_hwrng_read(struct hwrng * return tpm_get_random(chip, data, max); } +static bool tpm_is_hwrng_enabled(struct tpm_chip *chip) +{ + if (!IS_ENABLED(CONFIG_HW_RANDOM_TPM)) + return false; + if (tpm_is_firmware_upgrade(chip)) + return false; + if (chip->flags & TPM_CHIP_FLAG_HWRNG_DISABLED) + return false; + return true; +} + static int tpm_add_hwrng(struct tpm_chip *chip) { - if (!IS_ENABLED(CONFIG_HW_RANDOM_TPM) || tpm_is_firmware_upgrade(chip) || - chip->flags & TPM_CHIP_FLAG_HWRNG_DISABLED) + if (!tpm_is_hwrng_enabled(chip)) return 0; snprintf(chip->hwrng_name, sizeof(chip->hwrng_name), @@ -629,7 +639,7 @@ int tpm_chip_register(struct tpm_chip *c return 0; out_hwrng: - if (IS_ENABLED(CONFIG_HW_RANDOM_TPM) && !tpm_is_firmware_upgrade(chip)) + if (tpm_is_hwrng_enabled(chip)) hwrng_unregister(&chip->hwrng); out_ppi: tpm_bios_log_teardown(chip); @@ -654,8 +664,7 @@ EXPORT_SYMBOL_GPL(tpm_chip_register); void tpm_chip_unregister(struct tpm_chip *chip) { tpm_del_legacy_sysfs(chip); - if (IS_ENABLED(CONFIG_HW_RANDOM_TPM) && !tpm_is_firmware_upgrade(chip) && - !(chip->flags & TPM_CHIP_FLAG_HWRNG_DISABLED)) + if (tpm_is_hwrng_enabled(chip)) hwrng_unregister(&chip->hwrng); tpm_bios_log_teardown(chip); if (chip->flags & TPM_CHIP_FLAG_TPM2 && !tpm_is_firmware_upgrade(chip))