From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.remote-ip=100.103.45.18 ARC-Seal: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; cv=none; t=1793675002; b=JH23PyH1SQGr74Tm5lWwdrHQWhdnj7yOLWw0laB711iTMziFUsgantkUVREq99sF6XMn EQM4IU5CkKeHnyERLIevLXF5YUpujoZYWeimbEpuDfbcFOA5kgsFXrmvo+Ic3ChXMqFUH uKYXLyIhYdHUT+UrjgIKJM6oVX9yurY5JrY9vNL4iSb2612x0y37QtQm2X1/YBWN6GkCo nGQaXdUyAEjBw7WynwAZo3tpsBlvh5RmX27dm+A+hrp/Dh6d7B5TUhK3fXH61RZmt4dcg nIzHmuiIT+W2gUmdT5eh89Ra5UaquQtiYvciy/N7/sTQ8YYdUT6hyEyOV8e3rXkRpEA== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1793675002; h=Received:DKIM-Signature:From:To:Cc:Subject:Date:Message-ID:X-Mailer: In-Reply-To:References:MIME-Version:Content-Transfer-Encoding; bh=Sb2XMtjKsz+jI29azHxtIIZugzSbewTBfgbly0UTNlM=; b=RsvukDG6X25F4W2HRntmYUjAbPtzYthkG+x5oRrvEBEQAMoR9Jt78CxUhlIJJzuT1x26 BAPrYG+4bTNab4X7Agtlx/ld6yWFLULNn7ALztUrAgd8Yydhjd+PLY0l+64F3lcQWpVqd Xepmr/sVG5Jds/IY3Gz8HqBIGqNkOXlg4cxqU7abeoq3qrRrOtnFzwVvJYHbx5WoJY6uW fPTmKuu5E2JwxWUuXW34YcliNaNrRzd4zQMGO5w4kVUI2t/8T7iKAQgcNt8Vzx6M67sz9 1XPvDXey7JqvO6thQJcvJoB/uyffQdd1TlvY8Egf3y1fTPWwwzsjnZtg/ML65T1XHjQ== ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20260515 header.b=B8ukt+bh; arc=none smtp.remote-ip=100.103.45.18 Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (prime256v1)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with UTF8SMTPS id 4B265606A32D; Tue, 3 Nov 2026 03:03:22 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key, unprotected) header.d=kernel.org header.i=@kernel.org header.a=rsa-sha256 header.s=k20260515 header.b=B8ukt+bh Received: by smtp.kernel.org (Postfix) with UTF8SMTPSA id 5CB4E1F00A15; Tue, 3 Nov 2026 03:03:21 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=kernel.org; s=k20260515; t=1793675001; bh=Sb2XMtjKsz+jI29azHxtIIZugzSbewTBfgbly0UTNlM=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=B8ukt+bhl8JyK9XykNxTse88EYFzR6NjbR4YSc7f1QJUPo4SzvzQdTkdXUrct8958 AE4RgEzzZMqAZesur7+M4PbSkcbHqpDap8BAYTYpYCD+Lg5+EMe3HpE5HmPTvkswRv JxHT6Q3tfKZO09Jhnx/3KuhoU8UFcHzpfF3J41JeWuBg784tMC389l2e47B33Mtw4t whMjeb9XSKayXCs5bEbgFZU5Je3/zEo6tvJsvzjLISBFP1+xpg8L678VbKqtOS6xFo JaY5E6tPzkgWjsym0P0/cpibY7KceHlELo7X4ZP2iPsUKwfojMQZqqlf9U6zl/MlcV p2tMBsieJK6bA== From: Jarkko Sakkinen To: David Howells Cc: Eric Biggers , linux-integrity@vger.kernel.org, Mimi Zohar , keyrings@vger.kernel.org, Jarkko Sakkinen , Roberto Sassu , Dmitry Kasatkin , Eric Snowberg , Paul Moore , James Morris , "Serge E. Hallyn" , James Bottomley , Sumit Garg , linux-security-module@vger.kernel.org (open list:SECURITY SUBSYSTEM), linux-kernel@vger.kernel.org (open list) Subject: [RFC PATCH v2 08/11] KEYS: trusted: TEE: Synchronize session lifetime Date: Tue, 3 Nov 2026 05:02:13 +0200 Message-ID: <20261103030226.2685251-9-jarkko@kernel.org> X-Mailer: git-send-email 2.47.3 In-Reply-To: <20261103030226.2685251-1-jarkko@kernel.org> References: <20261103030226.2685251-1-jarkko@kernel.org> X-Mailing-List: linux-security-module@vger.kernel.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Even with sysfs bind attributes suppressed on trusted_key_driver, the parent TEE device can still remove trusted_key_device while live trusted keys keep trusted.ko loaded, and init_trusted() updated static calls only after backend init() had already registered key_type_trusted. Update the static calls before invoking backend init() and reset them on failure. In the TEE backend, guard session context state with a mutex, publish pvt_data.dev before registering key_type_trusted, sanitize pvt_data on probe failure and remove, and reject seal/unseal/get_random with -ENODEV when no active TEE session is bound. Signed-off-by: Jarkko Sakkinen --- security/keys/trusted-keys/trusted_core.c | 15 ++-- security/keys/trusted-keys/trusted_tee.c | 86 +++++++++++++++++------ 2 files changed, 75 insertions(+), 26 deletions(-) diff --git a/security/keys/trusted-keys/trusted_core.c b/security/keys/trusted-keys/trusted_core.c index 0509d9955f2a..11d7d296d063 100644 --- a/security/keys/trusted-keys/trusted_core.c +++ b/security/keys/trusted-keys/trusted_core.c @@ -373,14 +373,19 @@ static int __init init_trusted(void) if (!get_random) get_random = kernel_get_random; + static_call_update(trusted_key_seal, trusted_key_sources[i].ops->seal); + static_call_update(trusted_key_unseal, trusted_key_sources[i].ops->unseal); + static_call_update(trusted_key_get_random, get_random); + migratable = trusted_key_sources[i].ops->migratable; + ret = trusted_key_sources[i].ops->init(); if (!ret) { - static_call_update(trusted_key_seal, trusted_key_sources[i].ops->seal); - static_call_update(trusted_key_unseal, trusted_key_sources[i].ops->unseal); - static_call_update(trusted_key_get_random, get_random); - trusted_key_exit = trusted_key_sources[i].ops->exit; - migratable = trusted_key_sources[i].ops->migratable; + } else { + static_call_update(trusted_key_seal, NULL); + static_call_update(trusted_key_unseal, NULL); + static_call_update(trusted_key_get_random, NULL); + migratable = 0; } if (!ret || ret != -ENODEV) diff --git a/security/keys/trusted-keys/trusted_tee.c b/security/keys/trusted-keys/trusted_tee.c index 5d1288189e5c..a2ed16e0db3f 100644 --- a/security/keys/trusted-keys/trusted_tee.c +++ b/security/keys/trusted-keys/trusted_tee.c @@ -9,6 +9,7 @@ #include #include #include +#include #include #include #include @@ -56,6 +57,8 @@ struct trusted_key_tee_private { }; static struct trusted_key_tee_private pvt_data; +/* Do not hold this mutex across key type registration or unregistration. */ +static DEFINE_MUTEX(trusted_key_tee_mutex); /* * Have the TEE seal(encrypt) the symmetric key @@ -67,6 +70,12 @@ static int trusted_tee_seal(struct trusted_key_payload *p, char *datablob) struct tee_param param[4]; struct tee_shm *reg_shm = NULL; + mutex_lock(&trusted_key_tee_mutex); + if (!pvt_data.ctx) { + ret = -ENODEV; + goto out_unlock; + } + memset(&inv_arg, 0, sizeof(inv_arg)); memset(¶m, 0, sizeof(param)); @@ -74,7 +83,8 @@ static int trusted_tee_seal(struct trusted_key_payload *p, char *datablob) sizeof(p->key) + sizeof(p->blob)); if (IS_ERR(reg_shm)) { dev_err(pvt_data.dev, "shm register failed\n"); - return PTR_ERR(reg_shm); + ret = PTR_ERR(reg_shm); + goto out_unlock; } inv_arg.func = TA_CMD_SEAL; @@ -100,7 +110,8 @@ static int trusted_tee_seal(struct trusted_key_payload *p, char *datablob) } tee_shm_free(reg_shm); - +out_unlock: + mutex_unlock(&trusted_key_tee_mutex); return ret; } @@ -114,6 +125,12 @@ static int trusted_tee_unseal(struct trusted_key_payload *p, char *datablob) struct tee_param param[4]; struct tee_shm *reg_shm = NULL; + mutex_lock(&trusted_key_tee_mutex); + if (!pvt_data.ctx) { + ret = -ENODEV; + goto out_unlock; + } + memset(&inv_arg, 0, sizeof(inv_arg)); memset(¶m, 0, sizeof(param)); @@ -121,7 +138,8 @@ static int trusted_tee_unseal(struct trusted_key_payload *p, char *datablob) sizeof(p->key) + sizeof(p->blob)); if (IS_ERR(reg_shm)) { dev_err(pvt_data.dev, "shm register failed\n"); - return PTR_ERR(reg_shm); + ret = PTR_ERR(reg_shm); + goto out_unlock; } inv_arg.func = TA_CMD_UNSEAL; @@ -147,7 +165,8 @@ static int trusted_tee_unseal(struct trusted_key_payload *p, char *datablob) } tee_shm_free(reg_shm); - +out_unlock: + mutex_unlock(&trusted_key_tee_mutex); return ret; } @@ -161,13 +180,20 @@ static int trusted_tee_get_random(unsigned char *key, size_t key_len) struct tee_param param[4]; struct tee_shm *reg_shm = NULL; + mutex_lock(&trusted_key_tee_mutex); + if (!pvt_data.ctx) { + ret = -ENODEV; + goto out_unlock; + } + memset(&inv_arg, 0, sizeof(inv_arg)); memset(¶m, 0, sizeof(param)); reg_shm = tee_shm_register_kernel_buf(pvt_data.ctx, key, key_len); if (IS_ERR(reg_shm)) { dev_err(pvt_data.dev, "key shm register failed\n"); - return PTR_ERR(reg_shm); + ret = PTR_ERR(reg_shm); + goto out_unlock; } inv_arg.func = TA_CMD_GET_RANDOM; @@ -189,7 +215,8 @@ static int trusted_tee_get_random(unsigned char *key, size_t key_len) } tee_shm_free(reg_shm); - +out_unlock: + mutex_unlock(&trusted_key_tee_mutex); return ret; } @@ -205,50 +232,67 @@ static int optee_ctx_match(struct tee_ioctl_version_data *ver, const void *data) static int trusted_key_probe(struct tee_client_device *rng_device) { struct device *dev = &rng_device->dev; + struct tee_context *ctx; int ret; struct tee_ioctl_open_session_arg sess_arg; + mutex_lock(&trusted_key_tee_mutex); + if (pvt_data.ctx) { + ret = -EBUSY; + goto out_unlock; + } + memset(&sess_arg, 0, sizeof(sess_arg)); - pvt_data.ctx = tee_client_open_context(NULL, optee_ctx_match, NULL, - NULL); - if (IS_ERR(pvt_data.ctx)) - return -ENODEV; + ctx = tee_client_open_context(NULL, optee_ctx_match, NULL, NULL); + if (IS_ERR(ctx)) { + ret = -ENODEV; + goto out_unlock; + } memcpy(sess_arg.uuid, rng_device->id.uuid.b, TEE_IOCTL_UUID_LEN); sess_arg.clnt_login = TEE_IOCTL_LOGIN_REE_KERNEL; sess_arg.num_params = 0; - ret = tee_client_open_session(pvt_data.ctx, &sess_arg, NULL); + ret = tee_client_open_session(ctx, &sess_arg, NULL); if ((ret < 0) || (sess_arg.ret != 0)) { dev_err(dev, "tee_client_open_session failed, err: %x\n", sess_arg.ret); ret = -EINVAL; goto out_ctx; } + pvt_data.ctx = ctx; pvt_data.session_id = sess_arg.session; - - ret = register_key_type(&key_type_trusted); - if (ret < 0) - goto out_sess; - pvt_data.dev = dev; + mutex_unlock(&trusted_key_tee_mutex); - return 0; + ret = register_key_type(&key_type_trusted); + if (!ret) + return 0; -out_sess: - tee_client_close_session(pvt_data.ctx, pvt_data.session_id); + mutex_lock(&trusted_key_tee_mutex); + tee_client_close_session(ctx, pvt_data.session_id); out_ctx: - tee_client_close_context(pvt_data.ctx); - + tee_client_close_context(ctx); + pvt_data.ctx = NULL; + pvt_data.dev = NULL; + pvt_data.session_id = 0; +out_unlock: + mutex_unlock(&trusted_key_tee_mutex); return ret; } static void trusted_key_remove(struct tee_client_device *dev) { unregister_key_type(&key_type_trusted); + + mutex_lock(&trusted_key_tee_mutex); tee_client_close_session(pvt_data.ctx, pvt_data.session_id); tee_client_close_context(pvt_data.ctx); + pvt_data.ctx = NULL; + pvt_data.dev = NULL; + pvt_data.session_id = 0; + mutex_unlock(&trusted_key_tee_mutex); } static const struct tee_client_device_id trusted_key_id_table[] = { -- 2.47.3