From nobody Tue Nov 26 06:40:25 2024 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 31FD41CF2B9; Mon, 21 Oct 2024 05:39:34 +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=1729489175; cv=none; b=GXwQNdXJpMLe31sDcq/y03SK3XV2XEmf5JIQakRhshSFFOR/Cgh3tBWZl7ozhFP38G233aujQsazK+tI48XilvrCeu8V6Hk/+KWfY+0gvB5/10Y+ZIXM/PELLM/rhpKwJGP8UuqwXraYgpZv/CXSRHMD1L1u6TbHhVtZfAf/V+Q= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1729489175; c=relaxed/simple; bh=ClrpSHkVHottrltLmH7Rp4WsaHoZ3VFbzU0VMLWpIHE=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=buRtDcCx6DEl7CXi2UinzAHLAByS6bVE9CNT/g27f2Id5uPAANfEERl8CftoFsadO5DU9GjRFcE85gojvrC0pV22copYFi7Lf+Hn/jibu2s1UG0vC+urr9rZ1bhG96Yo0S1/aEzW4qbv85wNDIPgIzcMyAwff520abdQTmiMbUE= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=eB/ijjWx; 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="eB/ijjWx" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 04917C4CEE4; Mon, 21 Oct 2024 05:39:33 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1729489174; bh=ClrpSHkVHottrltLmH7Rp4WsaHoZ3VFbzU0VMLWpIHE=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=eB/ijjWx0Ki7CwzyliqkJIGspPsg1wLnv1gVWpAQchlLmnUvWIRrGVU2wWP48FHNR UnUFA+/sH31YjkbZFFIEEFaNGz5RFLz/lHj2uS5PtYHi3XBHIZZxOQRog76w9cMY8n OdZWmlgp1fMWQfJiGh50BJnW+CR9miA3WCNmR/Ou7u45kEPDaFoMUEqUJHI/ia1od8 Vzq3WZvD2a4b1rsJKl9vl1/JpJznz+ExEyLqLyp9Nn1oKr5hDTyCha/rYP3UhTO/E1 GfPHW02MXldtQA/qD+JYagAyPpxF6JrhAvJzdDl2hGAsSclrywS50eTY5sv1GJBEk/ vR7LYgzTExPww== From: Jarkko Sakkinen To: linux-integrity@vger.kernel.org, Peter Huewe , Jarkko Sakkinen , Jason Gunthorpe , James Bottomley Cc: David Howells , Mimi Zohar , Roberto Sassu , Stefan Berger , linux-kernel@vger.kernel.org, stable@vger.kernel.org Subject: [PATCH v7 1/5] tpm: Return on tpm2_create_null_primary() failure Date: Mon, 21 Oct 2024 08:39:15 +0300 Message-ID: <20241021053921.33274-2-jarkko@kernel.org> X-Mailer: git-send-email 2.47.0 In-Reply-To: <20241021053921.33274-1-jarkko@kernel.org> References: <20241021053921.33274-1-jarkko@kernel.org> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" tpm2_sessions_init() does not ignore the result of tpm2_create_null_primary(). Address this by returning -ENODEV to the caller. Given that upper layers cannot help healing the situation further, deal with the TPM error here by Cc: stable@vger.kernel.org # v6.10+ Fixes: d2add27cf2b8 ("tpm: Add NULL primary creation") Signed-off-by: Jarkko Sakkinen --- v7: - Add the error message back but fix it up a bit: 1. Remove 'TPM:' given dev_err(). 2. s/NULL/null/ as this has nothing to do with the macro in libc. 3. Fix the reasoning: null key creation failed v6: - Address: https://lore.kernel.org/linux-integrity/69c893e7-6b87-4daa-80db-44d1120e8= 0fe@linux.ibm.com/ as TPM RC is taken care of at the call site. Add also the missing documentation for the return values. v5: - Do not print klog messages on error, as tpm2_save_context() already takes care of this. v4: - Fixed up stable version. v3: - Handle TPM and POSIX error separately and return -ENODEV always back to the caller. v2: - Refined the commit message. --- drivers/char/tpm/tpm2-sessions.c | 11 +++++++++-- 1 file changed, 9 insertions(+), 2 deletions(-) diff --git a/drivers/char/tpm/tpm2-sessions.c b/drivers/char/tpm/tpm2-sessi= ons.c index d3521aadd43e..1e12e0b2492e 100644 --- a/drivers/char/tpm/tpm2-sessions.c +++ b/drivers/char/tpm/tpm2-sessions.c @@ -1347,14 +1347,21 @@ static int tpm2_create_null_primary(struct tpm_chip= *chip) * * Derive and context save the null primary and allocate memory in the * struct tpm_chip for the authorizations. + * + * Return: + * * 0 - OK + * * -errno - A system error + * * TPM_RC - A TPM error */ int tpm2_sessions_init(struct tpm_chip *chip) { int rc; =20 rc =3D tpm2_create_null_primary(chip); - if (rc) - dev_err(&chip->dev, "TPM: security failed (NULL seed derivation): %d\n",= rc); + if (rc) { + dev_err(&chip->dev, "null primary key creation failed with %d\n", rc); + return rc; + } =20 chip->auth =3D kmalloc(sizeof(*chip->auth), GFP_KERNEL); if (!chip->auth) --=20 2.47.0 From nobody Tue Nov 26 06:40:25 2024 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 4ABD8194AF3; Mon, 21 Oct 2024 05:39:40 +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=1729489180; cv=none; b=OmkR7Lug7eBX0r4T663QeLfR6ODDpRvQ8Kp4rtKly2RwOjUDuT87Fy/ITZ2re3Zc7q7NN9pBZ51D0ogZSf2bdx2Zob2x6aOXN41ULWYywNDvX1SwtgYp3ZNbPrC1B2vYE0r51oUCFCJcjP9fEH6Vorb8La/mUnHxVtLYs+qBd+Q= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1729489180; c=relaxed/simple; bh=D0m4paxP6P0gzIZy7P2Jr7htyTZRIO+jDExebpPsZQ4=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=MI2XRKmuIZ9uQDS5DnNY+jdwcmqTTK7lcPxpCtC3Uc4ftM3vZZs9/8/VMo2NzBXisYwXbIKF1CZouZuXp5C+mAonFqQaiJS7NyXLXYgrMCw5vqZnF4aXRbBAD0TVQtrD7LDRhRICR1DmB6CinuN10Iv2XW63zGPtmeUqZQgKRw0= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=plF3Rzne; 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="plF3Rzne" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 3AB4DC4CEC3; Mon, 21 Oct 2024 05:39:39 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1729489179; bh=D0m4paxP6P0gzIZy7P2Jr7htyTZRIO+jDExebpPsZQ4=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=plF3RznebuLsmKn3P4aGm240QSdRrTVuIS0UgAMa/HJoG1/bdnZKuhXyXTR7kAAv2 FXMoworq4UGjARs+SBbjUSuhjqYM/DEYRtY6wfBDNV5jiKkqLL4GA753+VMBUwnjR3 Qu36XzfR1terhsaMf6ntNwMbYrrTQc9OTunYFFpb/nojFKbLJCbmYj7dfEt1rPsou1 53BGOeF8qDCqk9nudBwP2FNMBHPXp8nglYlTUDJnAcDPPj9x4Q/n+AO79K+V/bYqlC OL6YL9Bi3pSFTSgNkqySulTBZQlXL5YhpNsbCpdKIiAltNuIAJ3jdE5rmjhKK+B9OV 2U+r9yhmZJTHA== From: Jarkko Sakkinen To: linux-integrity@vger.kernel.org, Peter Huewe , Jarkko Sakkinen , Jason Gunthorpe , James Bottomley Cc: David Howells , Mimi Zohar , Roberto Sassu , Stefan Berger , linux-kernel@vger.kernel.org, stable@vger.kernel.org Subject: [PATCH v7 2/5] tpm: Implement tpm2_load_null() rollback Date: Mon, 21 Oct 2024 08:39:16 +0300 Message-ID: <20241021053921.33274-3-jarkko@kernel.org> X-Mailer: git-send-email 2.47.0 In-Reply-To: <20241021053921.33274-1-jarkko@kernel.org> References: <20241021053921.33274-1-jarkko@kernel.org> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" tpm2_load_null() has weak and broken error handling: - The return value of tpm2_create_primary() is ignored. - Leaks TPM return codes from tpm2_load_context() to the caller. - If the key name comparison succeeds returns previous error instead of zero to the caller. Implement a proper error rollback. Cc: stable@vger.kernel.org # v6.10+ Fixes: eb24c9788cd9 ("tpm: disable the TPM if NULL name changes") Signed-off-by: Jarkko Sakkinen -- v6: - Address Stefan's remark: https://lore.kernel.org/linux-integrity/def4ec2d-584b-405f-9d5e-99267013c= 3c0@linux.ibm.com/ v5: - Fix the TPM error code leak from tpm2_load_context(). v4: - No changes. v3: - Update log messages. Previously the log message incorrectly stated on load failure that integrity check had been failed, even tho the check is done *after* the load operation. v2: - Refined the commit message. - Reverted tpm2_create_primary() changes. They are not required if tmp_null_key is used as the parameter. Reviewed-by: Stefan Berger --- drivers/char/tpm/tpm2-sessions.c | 43 +++++++++++++++++--------------- 1 file changed, 23 insertions(+), 20 deletions(-) diff --git a/drivers/char/tpm/tpm2-sessions.c b/drivers/char/tpm/tpm2-sessi= ons.c index 1e12e0b2492e..bdac11964b55 100644 --- a/drivers/char/tpm/tpm2-sessions.c +++ b/drivers/char/tpm/tpm2-sessions.c @@ -915,33 +915,36 @@ static int tpm2_parse_start_auth_session(struct tpm2_= auth *auth, =20 static int tpm2_load_null(struct tpm_chip *chip, u32 *null_key) { - int rc; unsigned int offset =3D 0; /* dummy offset for null seed context */ u8 name[SHA256_DIGEST_SIZE + 2]; + u32 tmp_null_key; + int rc; =20 rc =3D tpm2_load_context(chip, chip->null_key_context, &offset, - null_key); - if (rc !=3D -EINVAL) - return rc; + &tmp_null_key); + if (rc !=3D -EINVAL) { + if (!rc) + *null_key =3D tmp_null_key; + goto err; + } =20 - /* an integrity failure may mean the TPM has been reset */ - dev_err(&chip->dev, "NULL key integrity failure!\n"); - /* check the null name against what we know */ - tpm2_create_primary(chip, TPM2_RH_NULL, NULL, name); - if (memcmp(name, chip->null_key_name, sizeof(name)) =3D=3D 0) - /* name unchanged, assume transient integrity failure */ - return rc; - /* - * Fatal TPM failure: the NULL seed has actually changed, so - * the TPM must have been illegally reset. All in-kernel TPM - * operations will fail because the NULL primary can't be - * loaded to salt the sessions, but disable the TPM anyway so - * userspace programmes can't be compromised by it. - */ - dev_err(&chip->dev, "NULL name has changed, disabling TPM due to interfer= ence\n"); + rc =3D tpm2_create_primary(chip, TPM2_RH_NULL, &tmp_null_key, name); + if (rc) + goto err; + + /* Return the null key if the name has not been changed: */ + if (memcmp(name, chip->null_key_name, sizeof(name)) =3D=3D 0) { + *null_key =3D tmp_null_key; + return 0; + } + + /* Deduce from the name change TPM interference: */ + dev_err(&chip->dev, "the null key integrity check failedh\n"); + tpm2_flush_context(chip, tmp_null_key); chip->flags |=3D TPM_CHIP_FLAG_DISABLE; =20 - return rc; +err: + return rc ? -ENODEV : 0; } =20 /** --=20 2.47.0 From nobody Tue Nov 26 06:40:25 2024 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 C8FB41CEEAF; Mon, 21 Oct 2024 05:39:45 +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=1729489186; cv=none; b=e4FHZQ7nveDlE6/MpPAYK3Ah8Fw06/ziFWpYfHjWumlhUtSq6bo2jVM73CahOMqi1t6Pgvoh1Yxjdt2t5gecgG03aMfiVdKbdPhv1YM4IP8V+f5BFPwBtm7hDgU6vBaD7DuAwmZ4GxDXDWE/ki6f5iKPvMACXR67QoHd8xCKqhc= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1729489186; c=relaxed/simple; bh=sBQVOg/eM0xgxq2VxksERP5qeqkNKWn0D8iRZXy3xho=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=t2ofjmreodnKvvo4g1WbkHg3N56w8GyqpE6qoMZk7sPxlHf6NHBOdsC3b1XwNnWsHyTP/fWGoRoBjadSabgDZoxA6iQQ/SNkXc9WjzREkxEq8gxyUEyjGUsA81gLHUaCq0+whb5S1J+KOkk1YYwZy44XSLPCD/vCc6Ys0nZyIDE= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=VcpXxa1L; 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="VcpXxa1L" Received: by smtp.kernel.org (Postfix) with ESMTPSA id D72C0C4CEC3; Mon, 21 Oct 2024 05:39:44 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1729489185; bh=sBQVOg/eM0xgxq2VxksERP5qeqkNKWn0D8iRZXy3xho=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=VcpXxa1LXY6VcB6yfZJuUu1qwJqPY/5TBR9c4Jnv5JtlrMCPHz67D5oZ0LZ+1JOwJ dqZUfPTlQxsoP1wy8TBym5VNUK3v55zIahZVuLTqwSM/Gu3kO4axQ0a+tkhi1Rs6Zy Bmh53Wv8o8wZkP4Zr3FqnbR57w6qZJ+I0EyMNMlgwbagHDFiWOZU/QRVPdQn4UlhnY HV9tvN6dBGyzVCCl7GL9OqiYdp+wAEHSCyNAU9wWFkPjddlCNAHmRI9UjrhAY9Lk4f fnm5B3jUvcJozSwZ+w5UvgTPwYbaRDLiE8P4NBlqkqelF/Dc5zOCqDbX7W14K5c7Cj wC+SP8Ar2J69g== From: Jarkko Sakkinen To: linux-integrity@vger.kernel.org, Peter Huewe , Jarkko Sakkinen , Jason Gunthorpe , James Bottomley Cc: David Howells , Mimi Zohar , Roberto Sassu , Stefan Berger , linux-kernel@vger.kernel.org, stable@vger.kernel.org, Pengyu Ma Subject: [PATCH v7 3/5] tpm: flush the null key only when /dev/tpm0 is accessed Date: Mon, 21 Oct 2024 08:39:17 +0300 Message-ID: <20241021053921.33274-4-jarkko@kernel.org> X-Mailer: git-send-email 2.47.0 In-Reply-To: <20241021053921.33274-1-jarkko@kernel.org> References: <20241021053921.33274-1-jarkko@kernel.org> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" Instead of flushing and reloading the null key for every single auth session, flush it only when: 1. User space needs to access /dev/tpm{rm}0. 2. When going to sleep. 3. When unregistering the chip. This removes the need to load and swap the null key between TPM and regular memory per transaction, when the user space is not using the chip. Cc: stable@vger.kernel.org # v6.10+ Fixes: d2add27cf2b8 ("tpm: Add NULL primary creation") Tested-by: Pengyu Ma Signed-off-by: Jarkko Sakkinen --- v5: - No changes. v4: - Changed to bug fix as not having the patch there is a major hit to bootup times. v3: - Unchanged. v2: - Refined the commit message. - Added tested-by from Pengyu Ma . - Removed spurious pr_info() statement. --- drivers/char/tpm/tpm-chip.c | 13 +++++++++++++ drivers/char/tpm/tpm-dev-common.c | 7 +++++++ drivers/char/tpm/tpm-interface.c | 9 +++++++-- drivers/char/tpm/tpm2-cmd.c | 3 +++ drivers/char/tpm/tpm2-sessions.c | 17 ++++++++++++++--- include/linux/tpm.h | 2 ++ 6 files changed, 46 insertions(+), 5 deletions(-) diff --git a/drivers/char/tpm/tpm-chip.c b/drivers/char/tpm/tpm-chip.c index 854546000c92..0ea00e32f575 100644 --- a/drivers/char/tpm/tpm-chip.c +++ b/drivers/char/tpm/tpm-chip.c @@ -674,6 +674,19 @@ EXPORT_SYMBOL_GPL(tpm_chip_register); */ void tpm_chip_unregister(struct tpm_chip *chip) { +#ifdef CONFIG_TCG_TPM2_HMAC + int rc; + + rc =3D tpm_try_get_ops(chip); + if (!rc) { + if (chip->flags & TPM_CHIP_FLAG_TPM2) { + tpm2_flush_context(chip, chip->null_key); + chip->null_key =3D 0; + } + tpm_put_ops(chip); + } +#endif + tpm_del_legacy_sysfs(chip); if (tpm_is_hwrng_enabled(chip)) hwrng_unregister(&chip->hwrng); diff --git a/drivers/char/tpm/tpm-dev-common.c b/drivers/char/tpm/tpm-dev-c= ommon.c index 30b4c288c1bb..4eaa8e05c291 100644 --- a/drivers/char/tpm/tpm-dev-common.c +++ b/drivers/char/tpm/tpm-dev-common.c @@ -27,6 +27,13 @@ static ssize_t tpm_dev_transmit(struct tpm_chip *chip, s= truct tpm_space *space, struct tpm_header *header =3D (void *)buf; ssize_t ret, len; =20 +#ifdef CONFIG_TCG_TPM2_HMAC + if (chip->flags & TPM_CHIP_FLAG_TPM2) { + tpm2_flush_context(chip, chip->null_key); + chip->null_key =3D 0; + } +#endif + ret =3D tpm2_prepare_space(chip, space, buf, bufsiz); /* If the command is not implemented by the TPM, synthesize a * response with a TPM2_RC_COMMAND_CODE return for user-space. diff --git a/drivers/char/tpm/tpm-interface.c b/drivers/char/tpm/tpm-interf= ace.c index 5da134f12c9a..bfa47d48b0f2 100644 --- a/drivers/char/tpm/tpm-interface.c +++ b/drivers/char/tpm/tpm-interface.c @@ -379,10 +379,15 @@ int tpm_pm_suspend(struct device *dev) =20 rc =3D tpm_try_get_ops(chip); if (!rc) { - if (chip->flags & TPM_CHIP_FLAG_TPM2) + if (chip->flags & TPM_CHIP_FLAG_TPM2) { +#ifdef CONFIG_TCG_TPM2_HMAC + tpm2_flush_context(chip, chip->null_key); + chip->null_key =3D 0; +#endif tpm2_shutdown(chip, TPM2_SU_STATE); - else + } else { rc =3D tpm1_pm_suspend(chip, tpm_suspend_pcr); + } =20 tpm_put_ops(chip); } diff --git a/drivers/char/tpm/tpm2-cmd.c b/drivers/char/tpm/tpm2-cmd.c index 1e856259219e..aba024cbe7c5 100644 --- a/drivers/char/tpm/tpm2-cmd.c +++ b/drivers/char/tpm/tpm2-cmd.c @@ -364,6 +364,9 @@ void tpm2_flush_context(struct tpm_chip *chip, u32 hand= le) struct tpm_buf buf; int rc; =20 + if (!handle) + return; + rc =3D tpm_buf_init(&buf, TPM2_ST_NO_SESSIONS, TPM2_CC_FLUSH_CONTEXT); if (rc) { dev_warn(&chip->dev, "0x%08x was not flushed, out of memory\n", diff --git a/drivers/char/tpm/tpm2-sessions.c b/drivers/char/tpm/tpm2-sessi= ons.c index bdac11964b55..78c650ce4c9f 100644 --- a/drivers/char/tpm/tpm2-sessions.c +++ b/drivers/char/tpm/tpm2-sessions.c @@ -920,11 +920,19 @@ static int tpm2_load_null(struct tpm_chip *chip, u32 = *null_key) u32 tmp_null_key; int rc; =20 + /* fast path */ + if (chip->null_key) { + *null_key =3D chip->null_key; + return 0; + } + rc =3D tpm2_load_context(chip, chip->null_key_context, &offset, &tmp_null_key); if (rc !=3D -EINVAL) { - if (!rc) + if (!rc) { + chip->null_key =3D tmp_null_key; *null_key =3D tmp_null_key; + } goto err; } =20 @@ -934,6 +942,7 @@ static int tpm2_load_null(struct tpm_chip *chip, u32 *n= ull_key) =20 /* Return the null key if the name has not been changed: */ if (memcmp(name, chip->null_key_name, sizeof(name)) =3D=3D 0) { + chip->null_key =3D tmp_null_key; *null_key =3D tmp_null_key; return 0; } @@ -1006,7 +1015,6 @@ int tpm2_start_auth_session(struct tpm_chip *chip) tpm_buf_append_u16(&buf, TPM_ALG_SHA256); =20 rc =3D tpm_transmit_cmd(chip, &buf, 0, "start auth session"); - tpm2_flush_context(chip, null_key); =20 if (rc =3D=3D TPM2_RC_SUCCESS) rc =3D tpm2_parse_start_auth_session(auth, &buf); @@ -1338,7 +1346,10 @@ static int tpm2_create_null_primary(struct tpm_chip = *chip) =20 rc =3D tpm2_save_context(chip, null_key, chip->null_key_context, sizeof(chip->null_key_context), &offset); - tpm2_flush_context(chip, null_key); + if (rc) + tpm2_flush_context(chip, null_key); + else + chip->null_key =3D null_key; } =20 return rc; diff --git a/include/linux/tpm.h b/include/linux/tpm.h index e93ee8d936a9..4eb39db80e05 100644 --- a/include/linux/tpm.h +++ b/include/linux/tpm.h @@ -205,6 +205,8 @@ struct tpm_chip { #ifdef CONFIG_TCG_TPM2_HMAC /* details for communication security via sessions */ =20 + /* loaded null key */ + u32 null_key; /* saved context for NULL seed */ u8 null_key_context[TPM2_MAX_CONTEXT_SIZE]; /* name of NULL seed */ --=20 2.47.0 From nobody Tue Nov 26 06:40:25 2024 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 C567E1D0B9C; Mon, 21 Oct 2024 05:39:50 +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=1729489190; cv=none; b=erw2apU8YDlFbVbud3alKOkleU6uoA6NF1CDGsN/74dR4L4eOSyjiow/3zscrngcKQFqrepEmzzY+xtKoNVi5r9KdFrRBlx6vPWSw6TjWQmc504IPdY0n7cKOiF3eSucScD4gnOKqLLEUXP4LurAhCbe6vh+AsVTdi3qVeCoVNU= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1729489190; c=relaxed/simple; bh=zVwJDklgIRkad8lPk/v3KTWUu6spY32sDV7tSQf3Ico=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=sZXCu803Z+tmc1z4hzYkubWMDjGayO5u6qvq/kbo95V7ObFYQNLFe9C5SKSocSquo9Cw0JOe88z1xk723J4EnE0NoQtIVbI+VGPyiPptk2Vxs3bAsb2D0b1ESn8dReH9gOTFJibmiYUGMv4zHLMuiINLZKFOu7BaBHe2A5lC8mM= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=vOy04R3F; 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="vOy04R3F" Received: by smtp.kernel.org (Postfix) with ESMTPSA id A767FC4CEC3; Mon, 21 Oct 2024 05:39:49 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1729489190; bh=zVwJDklgIRkad8lPk/v3KTWUu6spY32sDV7tSQf3Ico=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=vOy04R3FlDlMdpsVknAi10CZtsPDha+rXagHZ5QT96NSjfSzCyZmBbfp46FM92H0o JEIFNYsirVP51YGm1hwAQFFqCBf0YSnx4rYQZ/LJNpmBOaRVEffZ4sivB7H4oAC5jl U8jB2av5ENXCfYhh4VCW7/1CdvSMqY6K+EDA26atflD1TiJbYa8lsOnWMMS5d3dKiF 8PrVT6cI4r9/MLvytPAIpf7hQS6pvmsrKAkSAIRxI1CESPflsBCTorm1xVcStl63Ok 6QD0kIbtCmWM0TBMk5XP7I0LL+2WBYaRIcK+H0HZvGeoMp7N9skjRS7Jo2+GiAFNbu ovrSbubpiStPQ== From: Jarkko Sakkinen To: linux-integrity@vger.kernel.org, Peter Huewe , Jarkko Sakkinen , Jason Gunthorpe , James Bottomley , Ard Biesheuvel Cc: David Howells , Mimi Zohar , Roberto Sassu , Stefan Berger , linux-kernel@vger.kernel.org, stable@vger.kernel.org Subject: [PATCH v7 4/5] tpm: Allocate chip->auth in tpm2_start_auth_session() Date: Mon, 21 Oct 2024 08:39:18 +0300 Message-ID: <20241021053921.33274-5-jarkko@kernel.org> X-Mailer: git-send-email 2.47.0 In-Reply-To: <20241021053921.33274-1-jarkko@kernel.org> References: <20241021053921.33274-1-jarkko@kernel.org> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" Move allocation of chip->auth to tpm2_start_auth_session() so that the field can be used as flag to tell whether auth session is active or not. Cc: stable@vger.kernel.org # v6.10+ Fixes: 699e3efd6c64 ("tpm: Add HMAC session start and end functions") Signed-off-by: Jarkko Sakkinen Reviewed-by: Stefan Berger --- v5: - No changes. v4: - Change to bug. v3: - No changes. v2: - A new patch. --- drivers/char/tpm/tpm2-sessions.c | 43 +++++++++++++++++++------------- 1 file changed, 25 insertions(+), 18 deletions(-) diff --git a/drivers/char/tpm/tpm2-sessions.c b/drivers/char/tpm/tpm2-sessi= ons.c index 78c650ce4c9f..6e52785de9fd 100644 --- a/drivers/char/tpm/tpm2-sessions.c +++ b/drivers/char/tpm/tpm2-sessions.c @@ -484,7 +484,8 @@ static void tpm2_KDFe(u8 z[EC_PT_SZ], const char *str, = u8 *pt_u, u8 *pt_v, sha256_final(&sctx, out); } =20 -static void tpm_buf_append_salt(struct tpm_buf *buf, struct tpm_chip *chip) +static void tpm_buf_append_salt(struct tpm_buf *buf, struct tpm_chip *chip, + struct tpm2_auth *auth) { struct crypto_kpp *kpp; struct kpp_request *req; @@ -543,7 +544,7 @@ static void tpm_buf_append_salt(struct tpm_buf *buf, st= ruct tpm_chip *chip) sg_set_buf(&s[0], chip->null_ec_key_x, EC_PT_SZ); sg_set_buf(&s[1], chip->null_ec_key_y, EC_PT_SZ); kpp_request_set_input(req, s, EC_PT_SZ*2); - sg_init_one(d, chip->auth->salt, EC_PT_SZ); + sg_init_one(d, auth->salt, EC_PT_SZ); kpp_request_set_output(req, d, EC_PT_SZ); crypto_kpp_compute_shared_secret(req); kpp_request_free(req); @@ -554,8 +555,7 @@ static void tpm_buf_append_salt(struct tpm_buf *buf, st= ruct tpm_chip *chip) * This works because KDFe fully consumes the secret before it * writes the salt */ - tpm2_KDFe(chip->auth->salt, "SECRET", x, chip->null_ec_key_x, - chip->auth->salt); + tpm2_KDFe(auth->salt, "SECRET", x, chip->null_ec_key_x, auth->salt); =20 out: crypto_free_kpp(kpp); @@ -854,6 +854,8 @@ int tpm_buf_check_hmac_response(struct tpm_chip *chip, = struct tpm_buf *buf, /* manually close the session if it wasn't consumed */ tpm2_flush_context(chip, auth->handle); memzero_explicit(auth, sizeof(*auth)); + kfree(auth); + chip->auth =3D NULL; } else { /* reset for next use */ auth->session =3D TPM_HEADER_SIZE; @@ -882,6 +884,8 @@ void tpm2_end_auth_session(struct tpm_chip *chip) =20 tpm2_flush_context(chip, auth->handle); memzero_explicit(auth, sizeof(*auth)); + kfree(auth); + chip->auth =3D NULL; } EXPORT_SYMBOL(tpm2_end_auth_session); =20 @@ -970,25 +974,29 @@ static int tpm2_load_null(struct tpm_chip *chip, u32 = *null_key) */ int tpm2_start_auth_session(struct tpm_chip *chip) { + struct tpm2_auth *auth; struct tpm_buf buf; - struct tpm2_auth *auth =3D chip->auth; - int rc; u32 null_key; + int rc; =20 - if (!auth) { - dev_warn_once(&chip->dev, "auth session is not active\n"); + if (chip->auth) { + dev_warn_once(&chip->dev, "auth session is active\n"); return 0; } =20 + auth =3D kzalloc(sizeof(*auth), GFP_KERNEL); + if (!auth) + return -ENOMEM; + rc =3D tpm2_load_null(chip, &null_key); if (rc) - goto out; + goto err; =20 auth->session =3D TPM_HEADER_SIZE; =20 rc =3D tpm_buf_init(&buf, TPM2_ST_NO_SESSIONS, TPM2_CC_START_AUTH_SESS); if (rc) - goto out; + goto err; =20 /* salt key handle */ tpm_buf_append_u32(&buf, null_key); @@ -1000,7 +1008,7 @@ int tpm2_start_auth_session(struct tpm_chip *chip) tpm_buf_append(&buf, auth->our_nonce, sizeof(auth->our_nonce)); =20 /* append encrypted salt and squirrel away unencrypted in auth */ - tpm_buf_append_salt(&buf, chip); + tpm_buf_append_salt(&buf, chip, auth); /* session type (HMAC, audit or policy) */ tpm_buf_append_u8(&buf, TPM2_SE_HMAC); =20 @@ -1021,10 +1029,13 @@ int tpm2_start_auth_session(struct tpm_chip *chip) =20 tpm_buf_destroy(&buf); =20 - if (rc) - goto out; + if (rc =3D=3D TPM2_RC_SUCCESS) { + chip->auth =3D auth; + return 0; + } =20 - out: +err: + kfree(auth); return rc; } EXPORT_SYMBOL(tpm2_start_auth_session); @@ -1377,10 +1388,6 @@ int tpm2_sessions_init(struct tpm_chip *chip) return rc; } =20 - chip->auth =3D kmalloc(sizeof(*chip->auth), GFP_KERNEL); - if (!chip->auth) - return -ENOMEM; - return rc; } #endif /* CONFIG_TCG_TPM2_HMAC */ --=20 2.47.0 From nobody Tue Nov 26 06:40:25 2024 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 CBE741CF7B1; Mon, 21 Oct 2024 05:39:55 +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=1729489195; cv=none; b=jQPjkfdjb+SkXkNWgFuQYWzZl+6r32bIUuz6UoDPgw3p6RPYHDC0OEGUtHp/xvk4sSCriUtKxKdi0A24zb2JxV3Uh1g2YckwPcXEUBrNhWk0OTUNVzJCZkploPyXdOTJ00xb8Kv57svjhjPbLDwoDpo8iQU+6XqZcTN4YfTncBM= ARC-Message-Signature: i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1729489195; c=relaxed/simple; bh=EKbaumhrez1Xq9qGRGrCO5GSCxZW2UvHqIoq1v904RI=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=VQ0gb/OZi0AJfn05t8rM7ZrMqyzdhvsLNWKHhjyXE0Joc1nolsGHwhIoZRv+LHr+zbcAK+V6kGjmWec4MjO/BJgojHODz1OSIGqseFrd2l2afz8PLbZy7/lEp2fsNq2AnWwKHd4nfml20/HoAl9bIbR+FTMFvNRp7bhQyEnrqnc= ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b=MV++9lG2; 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="MV++9lG2" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 3470CC4CEC3; Mon, 21 Oct 2024 05:39:55 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1729489195; bh=EKbaumhrez1Xq9qGRGrCO5GSCxZW2UvHqIoq1v904RI=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=MV++9lG2tpZXVhTx+hx83+MRldld4SqTTvJ480HZ+28/awqvvh3LIV7oEA7i2DeiY g6b0ynx2otMSxNuzNvSLcqSU6ZtRit1kZM3QOcJFEASOdsZFj1N5T8qENfJu6Lc7Al TLMNDrhQFJKJZowpSXLxQAOYai2ulpzh0D16ZcT7CQQq5mQbqDcxIprBVuraznXO0n q7rdJh+9Wv2b+QAbOyGlSTuk9NTEWNRgk1JSzTer831U/b/8FiL+ftumHd3MXZ13d4 h/EX091bYWGqJJt0YR5c/nmCVOpza0tcDjexGPS9JbUTpHLqSGNSSydgDK0ZjfTNiG 9E3EfrXP58a1w== From: Jarkko Sakkinen To: linux-integrity@vger.kernel.org, Peter Huewe , Jarkko Sakkinen , Jason Gunthorpe Cc: David Howells , James Bottomley , Mimi Zohar , Roberto Sassu , Stefan Berger , linux-kernel@vger.kernel.org, Pengyu Ma , stable@vger.kernel.org Subject: [PATCH v7 5/5] tpm: flush the auth session only when /dev/tpm0 is open Date: Mon, 21 Oct 2024 08:39:19 +0300 Message-ID: <20241021053921.33274-6-jarkko@kernel.org> X-Mailer: git-send-email 2.47.0 In-Reply-To: <20241021053921.33274-1-jarkko@kernel.org> References: <20241021053921.33274-1-jarkko@kernel.org> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable Content-Type: text/plain; charset="utf-8" Instead of flushing and reloading the auth session for every single transaction, keep the session open unless /dev/tpm0 is used. In practice this means applying TPM2_SA_CONTINUE_SESSION to the session attributes. Flush the session always when /dev/tpm0 is written. Reported-by: Pengyu Ma Closes: https://bugzilla.kernel.org/show_bug.cgi?id=3D219229 Cc: stable@vger.kernel.org # v6.10+ Fixes: 7ca110f2679b ("tpm: Address !chip->auth in tpm_buf_append_hmac_sessi= on*()") Tested-by: Pengyu Ma Signed-off-by: Jarkko Sakkinen --- v5: - No changes. v4: - Changed as bug. v3: - Refined the commit message. - Removed the conditional for applying TPM2_SA_CONTINUE_SESSION only when /dev/tpm0 is open. It is not required as the auth session is flushed, not saved. v2: - A new patch. --- drivers/char/tpm/tpm-chip.c | 1 + drivers/char/tpm/tpm-dev-common.c | 1 + drivers/char/tpm/tpm-interface.c | 1 + drivers/char/tpm/tpm2-sessions.c | 3 +++ 4 files changed, 6 insertions(+) diff --git a/drivers/char/tpm/tpm-chip.c b/drivers/char/tpm/tpm-chip.c index 0ea00e32f575..7a6bb30d1f32 100644 --- a/drivers/char/tpm/tpm-chip.c +++ b/drivers/char/tpm/tpm-chip.c @@ -680,6 +680,7 @@ void tpm_chip_unregister(struct tpm_chip *chip) rc =3D tpm_try_get_ops(chip); if (!rc) { if (chip->flags & TPM_CHIP_FLAG_TPM2) { + tpm2_end_auth_session(chip); tpm2_flush_context(chip, chip->null_key); chip->null_key =3D 0; } diff --git a/drivers/char/tpm/tpm-dev-common.c b/drivers/char/tpm/tpm-dev-c= ommon.c index 4eaa8e05c291..a3ed7a99a394 100644 --- a/drivers/char/tpm/tpm-dev-common.c +++ b/drivers/char/tpm/tpm-dev-common.c @@ -29,6 +29,7 @@ static ssize_t tpm_dev_transmit(struct tpm_chip *chip, st= ruct tpm_space *space, =20 #ifdef CONFIG_TCG_TPM2_HMAC if (chip->flags & TPM_CHIP_FLAG_TPM2) { + tpm2_end_auth_session(chip); tpm2_flush_context(chip, chip->null_key); chip->null_key =3D 0; } diff --git a/drivers/char/tpm/tpm-interface.c b/drivers/char/tpm/tpm-interf= ace.c index bfa47d48b0f2..2363018fa8fb 100644 --- a/drivers/char/tpm/tpm-interface.c +++ b/drivers/char/tpm/tpm-interface.c @@ -381,6 +381,7 @@ int tpm_pm_suspend(struct device *dev) if (!rc) { if (chip->flags & TPM_CHIP_FLAG_TPM2) { #ifdef CONFIG_TCG_TPM2_HMAC + tpm2_end_auth_session(chip); tpm2_flush_context(chip, chip->null_key); chip->null_key =3D 0; #endif diff --git a/drivers/char/tpm/tpm2-sessions.c b/drivers/char/tpm/tpm2-sessi= ons.c index 6e52785de9fd..a7079c7ec6d1 100644 --- a/drivers/char/tpm/tpm2-sessions.c +++ b/drivers/char/tpm/tpm2-sessions.c @@ -333,6 +333,9 @@ void tpm_buf_append_hmac_session(struct tpm_chip *chip,= struct tpm_buf *buf, } =20 #ifdef CONFIG_TCG_TPM2_HMAC + /* The first write to /dev/tpm{rm0} will flush the session. */ + attributes |=3D TPM2_SA_CONTINUE_SESSION; + /* * The Architecture Guide requires us to strip trailing zeros * before computing the HMAC --=20 2.47.0