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 5D4B8257851 for ; Tue, 30 Dec 2025 00:38:46 +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=1767055126; cv=none; b=WJ/yK+mgmEsFx1vJRQBuxTv3cCOPQlO8trZZ67drbrzMqC6UiKu8PHQvOw5Tp2vB6cp/5NNU0ViGSVsKZWXC768PrrZ3+79n0MgqYbziUVh+AoqrYOnyO/VHhAWZRJVWmwizl251uFwtzKBxaOPkd/swtWQJM+1gGpsmsCJgFX8= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1767055126; c=relaxed/simple; bh=29vt1nE45vlOVw3KLuNaF4QqaNMpJAnfSEefutn97Ks=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=aiouw98rI0MkKF4WHFDTMM6Ju6jZvWzmI2WcKZWvJaOCQ9FLMUrEkTmbFPDXOk8rfGpEI/RtqzKhYgLzNfs2505huMKCGvcsg/l7hSZj2T9CdgiPQgWp6ZOXhxfDQ8ZL20hnfi3PvSg8XU9dSZUZuUZfkHzWqNZulzIdGSrQaQI= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=CfGBwM0+; 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="CfGBwM0+" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 2C759C4CEF7; Tue, 30 Dec 2025 00:38:45 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1767055125; bh=29vt1nE45vlOVw3KLuNaF4QqaNMpJAnfSEefutn97Ks=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=CfGBwM0+2hdb8ZZWtbaZR7jVSZGW5+IxA3vN8Px/LEY2fgXFDLgZlOS10kUL62iQT sd6Mjris9A281oiVmNTc6mvBOjO4Od2ChPjgBdFv3Tz8/KetkJGYkHT93RMrJhJAsx K5WMWd98EesgAevv5d8mWfeWkpJYwyL8HEYHo/Keu3+pFSbdTD3q6ik/O2xVGmArA+ p8DNeaUT0jdVdsdHrSBtjQ9esOh5+nX//rj/Z7SIt8E2Z2gugMLEhMPz35Zrz9ufI/ zz1wLq0MpYjLf99editlZkHTF0hapnLV0NTcaXYj8n+cXwqxtkXu8Mi98cZVzL8qB0 PnkmBPdKLVt4A== From: Sasha Levin To: stable@vger.kernel.org Cc: Jarkko Sakkinen , Lai Yi , Jonathan McDowell , Roberto Sassu , Sasha Levin Subject: [PATCH 5.10.y] tpm: Cap the number of PCR banks Date: Mon, 29 Dec 2025 19:38:42 -0500 Message-ID: <20251230003843.1889960-1-sashal@kernel.org> X-Mailer: git-send-email 2.51.0 In-Reply-To: <2025122900-scorer-malformed-d565@gregkh> References: <2025122900-scorer-malformed-d565@gregkh> Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit From: Jarkko Sakkinen [ Upstream commit faf07e611dfa464b201223a7253e9dc5ee0f3c9e ] 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: stable@vger.kernel.org # v5.10+ Fixes: bcfff8384f6c ("tpm: dynamically allocate the allocated_banks array") Tested-by: Lai Yi Reviewed-by: Jonathan McDowell Reviewed-by: Roberto Sassu Signed-off-by: Jarkko Sakkinen [ added backward-compatible define for TPM_MAX_DIGEST_SIZE to support older ima_init.c code still using that macro name ] Signed-off-by: Sasha Levin --- drivers/char/tpm/tpm-chip.c | 1 - drivers/char/tpm/tpm1-cmd.c | 5 ----- drivers/char/tpm/tpm2-cmd.c | 8 +++----- include/linux/tpm.h | 9 ++++++--- 4 files changed, 9 insertions(+), 14 deletions(-) diff --git a/drivers/char/tpm/tpm-chip.c b/drivers/char/tpm/tpm-chip.c index 1e4f1a5049a5..528ed316150e 100644 --- a/drivers/char/tpm/tpm-chip.c +++ b/drivers/char/tpm/tpm-chip.c @@ -269,7 +269,6 @@ static void tpm_dev_release(struct device *dev) kfree(chip->work_space.context_buf); kfree(chip->work_space.session_buf); - kfree(chip->allocated_banks); kfree(chip); } diff --git a/drivers/char/tpm/tpm1-cmd.c b/drivers/char/tpm/tpm1-cmd.c index ca7158fa6e6c..28e562843fa5 100644 --- a/drivers/char/tpm/tpm1-cmd.c +++ b/drivers/char/tpm/tpm1-cmd.c @@ -794,11 +794,6 @@ 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 d0e11d7a3c08..0b683d991bed 100644 --- a/drivers/char/tpm/tpm2-cmd.c +++ b/drivers/char/tpm/tpm2-cmd.c @@ -574,11 +574,9 @@ 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 7868e847eee0..6d9d90f01b63 100644 --- a/include/linux/tpm.h +++ b/include/linux/tpm.h @@ -25,7 +25,10 @@ #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 +#define TPM_MAX_DIGEST_SIZE TPM2_MAX_DIGEST_SIZE struct tpm_chip; struct trusted_key_payload; @@ -44,7 +47,7 @@ enum tpm_algorithms { struct tpm_digest { u16 alg_id; - u8 digest[TPM_MAX_DIGEST_SIZE]; + u8 digest[TPM2_MAX_DIGEST_SIZE]; } __packed; struct tpm_bank_info { @@ -150,7 +153,7 @@ 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]; -- 2.51.0