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 8B38930AAB3; Thu, 27 Nov 2025 21:41:52 +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=1764279712; cv=none; b=dJgou2h/0SjsMw85aW9pC+adJ1/Hw2R/mT2Ng0zE9k+RGdXCUlh+ScT58l1YStZlMcyIyg6S2DqbiqWLgrBUtHRvcmimWIoYBC8d4/GLyP/9j/rwJyovtUDxno8fjDYGS0fD0SPIyCe+H7bCbrdnGsqc2dvugXxZn9Aw1QxZOyE= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1764279712; c=relaxed/simple; bh=x5IVYeyCJT+MJspL305CXeech68ZAZZvBLvSX33jO0A=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=pmknNsbRvXo23gVJtiPYVVJ9gXP9JmJJDvyLM9qVcMBOkl733oInYuM5+6k9Difb0h0FHXd4ioQvgQoq7NA02SWkEEU9acryY9TXC+QvgjMq3UrVkVDx0gO4L45VeojoPnaM19eBtRUF85EQj6ckvBYrUmK/MTyaESZxBGg1CUA= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=e/zY11KA; 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="e/zY11KA" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 5A56BC4CEF8; Thu, 27 Nov 2025 21:41:51 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1764279712; bh=x5IVYeyCJT+MJspL305CXeech68ZAZZvBLvSX33jO0A=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=e/zY11KA5fMZ1J1CwhB2yVmyYM6Jail/7zSPgkJR+aXcIPyw78TsXDGPJoD71F8Uw hGOEwCNE2nF07GYWVReIqgxDxvyR6qOVt9/u5uSsQhtz6OvKvR5Q2hD/p0zP1mlxDH lxVmMbk01YYI0ZM6WjZ9CCBZuRlQGP56pAYF1qLRj4MZYmPxsJIuk1OZAf5aVb+Na/ R4WuifE3aPHGuA5QhBNxyWGLPADYBfj0+h1WKy4mlGoO2Cnxxv7K7dt0f6XlPoqKW5 GNIAH30OlUtGKgXF1ybgpS3DjHYh+gzYcmyTqe7C4EVsMQ+7yu0XhNdVFmATDtJar4 LwSj1AhhjNngw== From: Jarkko Sakkinen To: linux-integrity@vger.kernel.org Cc: ross.philipson@oracle.com, Jonathan McDowell , Stefano Garzarella , Jarkko Sakkinen , Roberto Sassu , stable@vger.kernel.org, Jonathan McDowell , Peter Huewe , Jarkko Sakkinen , Jason Gunthorpe , linux-kernel@vger.kernel.org Subject: [PATCH v8 01/11] tpm: Cap the number of PCR banks Date: Thu, 27 Nov 2025 23:41:26 +0200 Message-ID: <20251127214138.3760029-2-jarkko@kernel.org> X-Mailer: git-send-email 2.52.0 In-Reply-To: <20251127214138.3760029-1-jarkko@kernel.org> References: <20251127214138.3760029-1-jarkko@kernel.org> Precedence: bulk X-Mailing-List: linux-integrity@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit From: Jarkko Sakkinen tpm2_get_pcr_allocation() does not cap any upper limit for the number of banks. Cap the limit to eight banks so that out of bounds values coming from external I/O cause on only limited harm. Cc: Roberto Sassu Cc: stable@vger.kernel.org # v5.10+ Fixes: bcfff8384f6c ("tpm: dynamically allocate the allocated_banks array") Reviewed-by: Jonathan McDowell Signed-off-by: Jarkko Sakkinen --- v8: - Remove unrelated change of removing tpm1_get_pcr_allocation. - Add the missing '\n' to the error message. v7: - In Ryzen desktop there is total three banks so yep, eight is probably much safer bet than four banks. Fixed the commit message as per remark from Jonathan: https://lore.kernel.org/linux-integrity/aPYg1N0TvrkG6AJI@earth.li/#t And with that added also reviewed-by. v6 - No changes. v5: - No changes. v4: - Revert spurious changes from include/linux/tpm.h. - Increase TPM2_MAX_BANKS to 8. - Rename TPM2_MAX_BANKS as TPM2_MAX_PCR_BANKS for the sake of clarity. v3: - Wrote a more clear commit message. - Fixed pr_err() message. v2: - A new patch. --- drivers/char/tpm/tpm1-cmd.c | 5 ----- drivers/char/tpm/tpm2-cmd.c | 8 +++----- include/linux/tpm.h | 8 +++++--- 3 files changed, 8 insertions(+), 13 deletions(-) diff --git a/drivers/char/tpm/tpm1-cmd.c b/drivers/char/tpm/tpm1-cmd.c index 11088bda4e68..6849f216ba0b 100644 --- a/drivers/char/tpm/tpm1-cmd.c +++ b/drivers/char/tpm/tpm1-cmd.c @@ -799,11 +799,6 @@ int tpm1_pm_suspend(struct tpm_chip *chip, u32 tpm_suspend_pcr) */ int tpm1_get_pcr_allocation(struct tpm_chip *chip) { - chip->allocated_banks = kcalloc(1, sizeof(*chip->allocated_banks), - GFP_KERNEL); - if (!chip->allocated_banks) - return -ENOMEM; - chip->allocated_banks[0].alg_id = TPM_ALG_SHA1; chip->allocated_banks[0].digest_size = hash_digest_size[HASH_ALGO_SHA1]; chip->allocated_banks[0].crypto_id = HASH_ALGO_SHA1; diff --git a/drivers/char/tpm/tpm2-cmd.c b/drivers/char/tpm/tpm2-cmd.c index 7d77f6fbc152..5b6ccf901623 100644 --- a/drivers/char/tpm/tpm2-cmd.c +++ b/drivers/char/tpm/tpm2-cmd.c @@ -538,11 +538,9 @@ ssize_t tpm2_get_pcr_allocation(struct tpm_chip *chip) nr_possible_banks = be32_to_cpup( (__be32 *)&buf.data[TPM_HEADER_SIZE + 5]); - - chip->allocated_banks = kcalloc(nr_possible_banks, - sizeof(*chip->allocated_banks), - GFP_KERNEL); - if (!chip->allocated_banks) { + if (nr_possible_banks > TPM2_MAX_PCR_BANKS) { + pr_err("tpm: out of bank capacity: %u > %u\n", + nr_possible_banks, TPM2_MAX_PCR_BANKS); rc = -ENOMEM; goto out; } diff --git a/include/linux/tpm.h b/include/linux/tpm.h index dc0338a783f3..eb0ff071bcae 100644 --- a/include/linux/tpm.h +++ b/include/linux/tpm.h @@ -26,7 +26,9 @@ #include #define TPM_DIGEST_SIZE 20 /* Max TPM v1.2 PCR size */ -#define TPM_MAX_DIGEST_SIZE SHA512_DIGEST_SIZE + +#define TPM2_MAX_DIGEST_SIZE SHA512_DIGEST_SIZE +#define TPM2_MAX_PCR_BANKS 8 struct tpm_chip; struct trusted_key_payload; @@ -68,7 +70,7 @@ enum tpm2_curves { struct tpm_digest { u16 alg_id; - u8 digest[TPM_MAX_DIGEST_SIZE]; + u8 digest[TPM2_MAX_DIGEST_SIZE]; } __packed; struct tpm_bank_info { @@ -189,7 +191,7 @@ struct tpm_chip { unsigned int groups_cnt; u32 nr_allocated_banks; - struct tpm_bank_info *allocated_banks; + struct tpm_bank_info allocated_banks[TPM2_MAX_PCR_BANKS]; #ifdef CONFIG_ACPI acpi_handle acpi_dev_handle; char ppi_version[TPM_PPI_VERSION_LEN + 1]; -- 2.52.0