- OP-TEE - lists.trustedfirmware.org

by Jens Wiklander

Hello arm-soc maintainers, Please pull this patch to enable loading of OP-TEE by the kernel. This feature is by default disabled and should probably always be so since it requires a quite specific security model to be secure. Thanks, Jens The following changes since commit eeac8ede17557680855031c6f305ece2378af326: Linux 6.3-rc2 (2023-03-12 16:36:44 -0700) are available in the Git repository at: https://git.linaro.org/people/jens.wiklander/linux-tee.git tags/optee-load-for-v6.4 for you to fetch changes up to f3040daab8104ac68e2b241bc93288f63b88a3c7: tee: optee: Add SMC for loading OP-TEE image (2023-04-03 08:57:49 +0200) ---------------------------------------------------------------- Add SMC for OP-TEE image loading Adds an SMC call for loading OP-TEE by the kernel. ---------------------------------------------------------------- Jeffrey Kardatzke (1): tee: optee: Add SMC for loading OP-TEE image Documentation/staging/tee.rst | 53 ++++++++++++++++ drivers/tee/optee/Kconfig | 17 ++++++ drivers/tee/optee/optee_msg.h | 12 ++++ drivers/tee/optee/optee_smc.h | 24 ++++++++ drivers/tee/optee/smc_abi.c | 137 ++++++++++++++++++++++++++++++++++++++++++ 5 files changed, 243 insertions(+)

2 years, 8 months

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[PATCH v13] tee: optee: Add SMC for loading OP-TEE image

by Jeffrey Kardatzke

Adds an SMC call that will pass an OP-TEE binary image to EL3 and instruct it to load it as the BL32 payload. This works in conjunction with a feature added to Trusted Firmware for ARMv8 and above architectures that supports this. The main purpose of this change is to facilitate updating the OP-TEE component on devices via a rootfs change rather than having to do a firmware update. Further details are linked to in the Kconfig file. Signed-off-by: Jeffrey Kardatzke <jkardatzke(a)chromium.org> Reviewed-by: Sumit Garg <sumit.garg(a)linaro.org> Signed-off-by: Jeffrey Kardatzke <jkardatzke(a)google.com> --- Changes in v13: - Documentation formatting changes Changes in v12: - Fixed checkpatch strict issues Changes in v11: - Fixed typo in tee.rst documentation Changes in v10: - Fixed tee.rst documentation formatting Changes in v9: - Add CPU hotplug callback to init on all cores at startup Changes in v8: - Renamed params and fixed alignment issue Changes in v7: - Added documentation to Documentation/staging/tee.rst Changes in v6: - Expanded Kconfig documentation Changes in v5: - Renamed config option - Added runtime warning when config is used Changes in v4: - Update commit message - Added more documentation - Renamed config option, added ARM64 dependency Changes in v3: - Removed state tracking for driver reload - Check UID of service to verify it needs image load Changes in v2: - Fixed compile issue when feature is disabled - Addressed minor comments - Added state tracking for driver reload Documentation/staging/tee.rst | 53 +++++++++++++ drivers/tee/optee/Kconfig | 17 +++++ drivers/tee/optee/optee_msg.h | 12 +++ drivers/tee/optee/optee_smc.h | 24 ++++++ drivers/tee/optee/smc_abi.c | 137 ++++++++++++++++++++++++++++++++++ 5 files changed, 243 insertions(+) diff --git a/Documentation/staging/tee.rst b/Documentation/staging/tee.rst index 498343c7ab08..22baa077a3b9 100644 --- a/Documentation/staging/tee.rst +++ b/Documentation/staging/tee.rst @@ -214,6 +214,57 @@ call is done from the thread assisting the interrupt handler. This is a building block for OP-TEE OS in secure world to implement the top half and bottom half style of device drivers. +OPTEE_INSECURE_LOAD_IMAGE Kconfig option +---------------------------------------- + +The OPTEE_INSECURE_LOAD_IMAGE Kconfig option enables the ability to load the +BL32 OP-TEE image from the kernel after the kernel boots, rather than loading +it from the firmware before the kernel boots. This also requires enabling the +corresponding option in Trusted Firmware for Arm. The Trusted Firmware for Arm +documentation [8] explains the security threat associated with enabling this as +well as mitigations at the firmware and platform level. + +There are additional attack vectors/mitigations for the kernel that should be +addressed when using this option. + +1. Boot chain security. + + * Attack vector: Replace the OP-TEE OS image in the rootfs to gain control of + the system. + + * Mitigation: There must be boot chain security that verifies the kernel and + rootfs, otherwise an attacker can modify the loaded OP-TEE binary by + modifying it in the rootfs. + +2. Alternate boot modes. + + * Attack vector: Using an alternate boot mode (i.e. recovery mode), the + OP-TEE driver isn't loaded, leaving the SMC hole open. + + * Mitigation: If there are alternate methods of booting the device, such as a + recovery mode, it should be ensured that the same mitigations are applied + in that mode. + +3. Attacks prior to SMC invocation. + + * Attack vector: Code that is executed prior to issuing the SMC call to load + OP-TEE can be exploited to then load an alternate OS image. + + * Mitigation: The OP-TEE driver must be loaded before any potential attack + vectors are opened up. This should include mounting of any modifiable + filesystems, opening of network ports or communicating with external + devices (e.g. USB). + +4. Blocking SMC call to load OP-TEE. + + * Attack vector: Prevent the driver from being probed, so the SMC call to + load OP-TEE isn't executed when desired, leaving it open to being executed + later and loading a modified OS. + + * Mitigation: It is recommended to build the OP-TEE driver as builtin driver + rather than as a module to prevent exploits that may cause the module to + not be loaded. + AMD-TEE driver ============== @@ -309,3 +360,5 @@ References [6] include/linux/psp-tee.h [7] drivers/tee/amdtee/amdtee_if.h + +[8] https://trustedfirmware-a.readthedocs.io/en/latest/threat_model/threat_mode… diff --git a/drivers/tee/optee/Kconfig b/drivers/tee/optee/Kconfig index f121c224e682..70898bbd5809 100644 --- a/drivers/tee/optee/Kconfig +++ b/drivers/tee/optee/Kconfig @@ -7,3 +7,20 @@ config OPTEE help This implements the OP-TEE Trusted Execution Environment (TEE) driver. + +config OPTEE_INSECURE_LOAD_IMAGE + bool "Load OP-TEE image as firmware" + default n + depends on OPTEE && ARM64 + help + This loads the BL32 image for OP-TEE as firmware when the driver is + probed. This returns -EPROBE_DEFER until the firmware is loadable from + the filesystem which is determined by checking the system_state until + it is in SYSTEM_RUNNING. This also requires enabling the corresponding + option in Trusted Firmware for Arm. The documentation there explains + the security threat associated with enabling this as well as + mitigations at the firmware and platform level. + https://trustedfirmware-a.readthedocs.io/en/latest/threat_model/threat_mode… + + Additional documentation on kernel security risks are at + Documentation/staging/tee.rst. diff --git a/drivers/tee/optee/optee_msg.h b/drivers/tee/optee/optee_msg.h index 70e9cc2ee96b..e8840a82b983 100644 --- a/drivers/tee/optee/optee_msg.h +++ b/drivers/tee/optee/optee_msg.h @@ -241,11 +241,23 @@ struct optee_msg_arg { * 384fb3e0-e7f8-11e3-af63-0002a5d5c51b. * Represented in 4 32-bit words in OPTEE_MSG_UID_0, OPTEE_MSG_UID_1, * OPTEE_MSG_UID_2, OPTEE_MSG_UID_3. + * + * In the case where the OP-TEE image is loaded by the kernel, this will + * initially return an alternate UID to reflect that we are communicating with + * the TF-A image loading service at that time instead of OP-TEE. That UID is: + * a3fbeab1-1246-315d-c7c4-06b9c03cbea4. + * Represented in 4 32-bit words in OPTEE_MSG_IMAGE_LOAD_UID_0, + * OPTEE_MSG_IMAGE_LOAD_UID_1, OPTEE_MSG_IMAGE_LOAD_UID_2, + * OPTEE_MSG_IMAGE_LOAD_UID_3. */ #define OPTEE_MSG_UID_0 0x384fb3e0 #define OPTEE_MSG_UID_1 0xe7f811e3 #define OPTEE_MSG_UID_2 0xaf630002 #define OPTEE_MSG_UID_3 0xa5d5c51b +#define OPTEE_MSG_IMAGE_LOAD_UID_0 0xa3fbeab1 +#define OPTEE_MSG_IMAGE_LOAD_UID_1 0x1246315d +#define OPTEE_MSG_IMAGE_LOAD_UID_2 0xc7c406b9 +#define OPTEE_MSG_IMAGE_LOAD_UID_3 0xc03cbea4 #define OPTEE_MSG_FUNCID_CALLS_UID 0xFF01 /* diff --git a/drivers/tee/optee/optee_smc.h b/drivers/tee/optee/optee_smc.h index 73b5e7760d10..7d9fa426505b 100644 --- a/drivers/tee/optee/optee_smc.h +++ b/drivers/tee/optee/optee_smc.h @@ -104,6 +104,30 @@ struct optee_smc_call_get_os_revision_result { unsigned long reserved1; }; +/* + * Load Trusted OS from optee/tee.bin in the Linux firmware. + * + * WARNING: Use this cautiously as it could lead to insecure loading of the + * Trusted OS. + * This SMC instructs EL3 to load a binary and execute it as the Trusted OS. + * + * Call register usage: + * a0 SMC Function ID, OPTEE_SMC_CALL_LOAD_IMAGE + * a1 Upper 32bit of a 64bit size for the payload + * a2 Lower 32bit of a 64bit size for the payload + * a3 Upper 32bit of the physical address for the payload + * a4 Lower 32bit of the physical address for the payload + * + * The payload is in the OP-TEE image format. + * + * Returns result in a0, 0 on success and an error code otherwise. + */ +#define OPTEE_SMC_FUNCID_LOAD_IMAGE 2 +#define OPTEE_SMC_CALL_LOAD_IMAGE \ + ARM_SMCCC_CALL_VAL(ARM_SMCCC_FAST_CALL, ARM_SMCCC_SMC_32, \ + ARM_SMCCC_OWNER_TRUSTED_OS_END, \ + OPTEE_SMC_FUNCID_LOAD_IMAGE) + /* * Call with struct optee_msg_arg as argument * diff --git a/drivers/tee/optee/smc_abi.c b/drivers/tee/optee/smc_abi.c index a1c1fa1a9c28..6e1f023d50c6 100644 --- a/drivers/tee/optee/smc_abi.c +++ b/drivers/tee/optee/smc_abi.c @@ -7,10 +7,13 @@ #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt #include <linux/arm-smccc.h> +#include <linux/cpuhotplug.h> #include <linux/errno.h> +#include <linux/firmware.h> #include <linux/interrupt.h> #include <linux/io.h> #include <linux/irqdomain.h> +#include <linux/kernel.h> #include <linux/mm.h> #include <linux/module.h> #include <linux/of.h> @@ -1149,6 +1152,22 @@ static bool optee_msg_api_uid_is_optee_api(optee_invoke_fn *invoke_fn) return false; } +#ifdef CONFIG_OPTEE_INSECURE_LOAD_IMAGE +static bool optee_msg_api_uid_is_optee_image_load(optee_invoke_fn *invoke_fn) +{ + struct arm_smccc_res res; + + invoke_fn(OPTEE_SMC_CALLS_UID, 0, 0, 0, 0, 0, 0, 0, &res); + + if (res.a0 == OPTEE_MSG_IMAGE_LOAD_UID_0 && + res.a1 == OPTEE_MSG_IMAGE_LOAD_UID_1 && + res.a2 == OPTEE_MSG_IMAGE_LOAD_UID_2 && + res.a3 == OPTEE_MSG_IMAGE_LOAD_UID_3) + return true; + return false; +} +#endif + static void optee_msg_get_os_revision(optee_invoke_fn *invoke_fn) { union { @@ -1354,6 +1373,120 @@ static void optee_shutdown(struct platform_device *pdev) optee_disable_shm_cache(optee); } +#ifdef CONFIG_OPTEE_INSECURE_LOAD_IMAGE + +#define OPTEE_FW_IMAGE "optee/tee.bin" + +static optee_invoke_fn *cpuhp_invoke_fn; + +static int optee_cpuhp_probe(unsigned int cpu) +{ + /* + * Invoking a call on a CPU will cause OP-TEE to perform the required + * setup for that CPU. Just invoke the call to get the UID since that + * has no side effects. + */ + if (optee_msg_api_uid_is_optee_api(cpuhp_invoke_fn)) + return 0; + else + return -EINVAL; +} + +static int optee_load_fw(struct platform_device *pdev, + optee_invoke_fn *invoke_fn) +{ + const struct firmware *fw = NULL; + struct arm_smccc_res res; + phys_addr_t data_pa; + u8 *data_buf = NULL; + u64 data_size; + u32 data_pa_high, data_pa_low; + u32 data_size_high, data_size_low; + int rc; + int hp_state; + + if (!optee_msg_api_uid_is_optee_image_load(invoke_fn)) + return 0; + + rc = request_firmware(&fw, OPTEE_FW_IMAGE, &pdev->dev); + if (rc) { + /* + * The firmware in the rootfs will not be accessible until we + * are in the SYSTEM_RUNNING state, so return EPROBE_DEFER until + * that point. + */ + if (system_state < SYSTEM_RUNNING) + return -EPROBE_DEFER; + goto fw_err; + } + + data_size = fw->size; + /* + * This uses the GFP_DMA flag to ensure we are allocated memory in the + * 32-bit space since TF-A cannot map memory beyond the 32-bit boundary. + */ + data_buf = kmalloc(fw->size, GFP_KERNEL | GFP_DMA); + if (!data_buf) { + rc = -ENOMEM; + goto fw_err; + } + memcpy(data_buf, fw->data, fw->size); + data_pa = virt_to_phys(data_buf); + reg_pair_from_64(&data_pa_high, &data_pa_low, data_pa); + reg_pair_from_64(&data_size_high, &data_size_low, data_size); + goto fw_load; + +fw_err: + pr_warn("image loading failed\n"); + data_pa_high = 0; + data_pa_low = 0; + data_size_high = 0; + data_size_low = 0; + +fw_load: + /* + * Always invoke the SMC, even if loading the image fails, to indicate + * to EL3 that we have passed the point where it should allow invoking + * this SMC. + */ + pr_warn("OP-TEE image loaded from kernel, this can be insecure"); + invoke_fn(OPTEE_SMC_CALL_LOAD_IMAGE, data_size_high, data_size_low, + data_pa_high, data_pa_low, 0, 0, 0, &res); + if (!rc) + rc = res.a0; + if (fw) + release_firmware(fw); + kfree(data_buf); + + if (!rc) { + /* + * We need to initialize OP-TEE on all other running cores as + * well. Any cores that aren't running yet will get initialized + * when they are brought up by the power management functions in + * TF-A which are registered by the OP-TEE SPD. Due to that we + * can un-register the callback right after registering it. + */ + cpuhp_invoke_fn = invoke_fn; + hp_state = cpuhp_setup_state(CPUHP_AP_ONLINE_DYN, "optee:probe", + optee_cpuhp_probe, NULL); + if (hp_state < 0) { + pr_warn("Failed with CPU hotplug setup for OP-TEE"); + return -EINVAL; + } + cpuhp_remove_state(hp_state); + cpuhp_invoke_fn = NULL; + } + + return rc; +} +#else +static inline int optee_load_fw(struct platform_device *pdev, + optee_invoke_fn *invoke_fn) +{ + return 0; +} +#endif + static int optee_probe(struct platform_device *pdev) { optee_invoke_fn *invoke_fn; @@ -1372,6 +1505,10 @@ static int optee_probe(struct platform_device *pdev) if (IS_ERR(invoke_fn)) return PTR_ERR(invoke_fn); + rc = optee_load_fw(pdev, invoke_fn); + if (rc) + return rc; + if (!optee_msg_api_uid_is_optee_api(invoke_fn)) { pr_warn("api uid mismatch\n"); return -EINVAL; -- 2.40.0.348.gf938b09366-goog

2 years, 8 months

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[GIT PULL] OP-TEE per-cpu irq for v6.4.

by Jens Wiklander

Hello arm-soc maintainers, Please pull these patches which add support for using per-cpu interrutps to signal asynchronous notifications from OP-TEE in secure world to the OP-TEE driver. Thanks, Jens The following changes since commit eeac8ede17557680855031c6f305ece2378af326: Linux 6.3-rc2 (2023-03-12 16:36:44 -0700) are available in the Git repository at: https://git.linaro.org/people/jens.wiklander/linux-tee.git/ tags/optee-per-cpu-irq-for-v6.4 for you to fetch changes up to b3b4ced12c1bc829888803ce07fff317e590ec1c: optee: add per cpu asynchronous notification (2023-03-30 08:27:05 +0200) ---------------------------------------------------------------- Add OP-TEE per cpu asynchronous notification Adds support for signalling from secure world with per-cpu interrupts in addition to edge-triggered peripheral interrupts. ---------------------------------------------------------------- Etienne Carriere (2): dt-bindings: optee driver interrupt can be a per-cpu interrupt optee: add per cpu asynchronous notification .../bindings/arm/firmware/linaro,optee-tz.yaml | 3 +- drivers/tee/optee/optee_private.h | 24 ++++ drivers/tee/optee/smc_abi.c | 122 ++++++++++++++++++++- 3 files changed, 144 insertions(+), 5 deletions(-)

2 years, 8 months

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Re: rk3399 issue: no DMA in Linux with mainline TF-A and U-Boot SPL

by chf.fritz＠googlemail.com

The content of this message was lost. It was probably cross-posted to multiple lists and previously handled on another list.

2 years, 8 months

1
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Re: rk3399 issue: no DMA in Linux with mainline TF-A and U-Boot SPL

by linux＠armlinux.org.uk

The content of this message was lost. It was probably cross-posted to multiple lists and previously handled on another list.

2 years, 8 months

1
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Re: rk3399 issue: no DMA in Linux with mainline TF-A and U-Boot SPL

by chf.fritz＠googlemail.com

The content of this message was lost. It was probably cross-posted to multiple lists and previously handled on another list.

2 years, 8 months

1
0
0 0

rk3399 issue: no DMA in Linux with mainline TF-A and U-Boot SPL

by chf.fritz＠googlemail.com

The content of this message was lost. It was probably cross-posted to multiple lists and previously handled on another list.

2 years, 8 months

1
0
0 0

[PATCH v12] tee: optee: Add SMC for loading OP-TEE image

by Jeffrey Kardatzke

Adds an SMC call that will pass an OP-TEE binary image to EL3 and instruct it to load it as the BL32 payload. This works in conjunction with a feature added to Trusted Firmware for ARMv8 and above architectures that supports this. The main purpose of this change is to facilitate updating the OP-TEE component on devices via a rootfs change rather than having to do a firmware update. Further details are linked to in the Kconfig file. Signed-off-by: Jeffrey Kardatzke <jkardatzke(a)chromium.org> Reviewed-by: Sumit Garg <sumit.garg(a)linaro.org> Signed-off-by: Jeffrey Kardatzke <jkardatzke(a)google.com> --- Changes in v12: - Fixed checkpatch strict issues Changes in v11: - Fixed typo in tee.rst documentation Changes in v10: - Fixed tee.rst documentation formatting Changes in v9: - Add CPU hotplug callback to init on all cores at startup Changes in v8: - Renamed params and fixed alignment issue Changes in v7: - Added documentation to Documentation/staging/tee.rst Changes in v6: - Expanded Kconfig documentation Changes in v5: - Renamed config option - Added runtime warning when config is used Changes in v4: - Update commit message - Added more documentation - Renamed config option, added ARM64 dependency Changes in v3: - Removed state tracking for driver reload - Check UID of service to verify it needs image load Changes in v2: - Fixed compile issue when feature is disabled - Addressed minor comments - Added state tracking for driver reload Documentation/staging/tee.rst | 41 ++++++++++ drivers/tee/optee/Kconfig | 17 +++++ drivers/tee/optee/optee_msg.h | 12 +++ drivers/tee/optee/optee_smc.h | 24 ++++++ drivers/tee/optee/smc_abi.c | 137 ++++++++++++++++++++++++++++++++++ 5 files changed, 231 insertions(+) diff --git a/Documentation/staging/tee.rst b/Documentation/staging/tee.rst index 498343c7ab08..b11e9053bc99 100644 --- a/Documentation/staging/tee.rst +++ b/Documentation/staging/tee.rst @@ -214,6 +214,47 @@ call is done from the thread assisting the interrupt handler. This is a building block for OP-TEE OS in secure world to implement the top half and bottom half style of device drivers. +OPTEE_INSECURE_LOAD_IMAGE Kconfig option +---------------------------------------- + +The OPTEE_INSECURE_LOAD_IMAGE Kconfig option enables the ability to load the +BL32 OP-TEE image from the kernel after the kernel boots, rather than loading +it from the firmware before the kernel boots. This also requires enabling the +corresponding option in Trusted Firmware for Arm. The documentation there +explains the security threat associated with enabling this as well as +mitigations at the firmware and platform level. +https://trustedfirmware-a.readthedocs.io/en/latest/threat_model/threat_model.html + +There are additional attack vectors/mitigations for the kernel that should be +addressed when using this option. + +1. Boot chain security. + Attack vector: Replace the OP-TEE OS image in the rootfs to gain control of + the system. + Mitigation: There must be boot chain security that verifies the kernel and + rootfs, otherwise an attacker can modify the loaded OP-TEE binary by + modifying it in the rootfs. +2. Alternate boot modes. + Attack vector: Using an alternate boot mode (i.e. recovery mode), the OP-TEE + driver isn't loaded, leaving the SMC hole open. + Mitigation: If there are alternate methods of booting the device, such as a + recovery mode, it should be ensured that the same mitigations are applied in + that mode. +3. Attacks prior to SMC invocation. + Attack vector: Code that is executed prior to issuing the SMC call to load + OP-TEE can be exploited to then load an alternate OS image. + Mitigation: The OP-TEE driver must be loaded before any potential attack + vectors are opened up. This should include mounting of any modifiable + filesystems, opening of network ports or communicating with external devices + (e.g. USB). +4. Blocking SMC call to load OP-TEE. + Attack vector: Prevent the driver from being probed, so the SMC call to load + OP-TEE isn't executed when desired, leaving it open to being executed later + and loading a modified OS. + Mitigation: It is recommended to build the OP-TEE driver as an included + driver rather than a module to prevent exploits that may cause the module to + not be loaded. + AMD-TEE driver ============== diff --git a/drivers/tee/optee/Kconfig b/drivers/tee/optee/Kconfig index f121c224e682..70898bbd5809 100644 --- a/drivers/tee/optee/Kconfig +++ b/drivers/tee/optee/Kconfig @@ -7,3 +7,20 @@ config OPTEE help This implements the OP-TEE Trusted Execution Environment (TEE) driver. + +config OPTEE_INSECURE_LOAD_IMAGE + bool "Load OP-TEE image as firmware" + default n + depends on OPTEE && ARM64 + help + This loads the BL32 image for OP-TEE as firmware when the driver is + probed. This returns -EPROBE_DEFER until the firmware is loadable from + the filesystem which is determined by checking the system_state until + it is in SYSTEM_RUNNING. This also requires enabling the corresponding + option in Trusted Firmware for Arm. The documentation there explains + the security threat associated with enabling this as well as + mitigations at the firmware and platform level. + https://trustedfirmware-a.readthedocs.io/en/latest/threat_model/threat_mode… + + Additional documentation on kernel security risks are at + Documentation/staging/tee.rst. diff --git a/drivers/tee/optee/optee_msg.h b/drivers/tee/optee/optee_msg.h index 70e9cc2ee96b..e8840a82b983 100644 --- a/drivers/tee/optee/optee_msg.h +++ b/drivers/tee/optee/optee_msg.h @@ -241,11 +241,23 @@ struct optee_msg_arg { * 384fb3e0-e7f8-11e3-af63-0002a5d5c51b. * Represented in 4 32-bit words in OPTEE_MSG_UID_0, OPTEE_MSG_UID_1, * OPTEE_MSG_UID_2, OPTEE_MSG_UID_3. + * + * In the case where the OP-TEE image is loaded by the kernel, this will + * initially return an alternate UID to reflect that we are communicating with + * the TF-A image loading service at that time instead of OP-TEE. That UID is: + * a3fbeab1-1246-315d-c7c4-06b9c03cbea4. + * Represented in 4 32-bit words in OPTEE_MSG_IMAGE_LOAD_UID_0, + * OPTEE_MSG_IMAGE_LOAD_UID_1, OPTEE_MSG_IMAGE_LOAD_UID_2, + * OPTEE_MSG_IMAGE_LOAD_UID_3. */ #define OPTEE_MSG_UID_0 0x384fb3e0 #define OPTEE_MSG_UID_1 0xe7f811e3 #define OPTEE_MSG_UID_2 0xaf630002 #define OPTEE_MSG_UID_3 0xa5d5c51b +#define OPTEE_MSG_IMAGE_LOAD_UID_0 0xa3fbeab1 +#define OPTEE_MSG_IMAGE_LOAD_UID_1 0x1246315d +#define OPTEE_MSG_IMAGE_LOAD_UID_2 0xc7c406b9 +#define OPTEE_MSG_IMAGE_LOAD_UID_3 0xc03cbea4 #define OPTEE_MSG_FUNCID_CALLS_UID 0xFF01 /* diff --git a/drivers/tee/optee/optee_smc.h b/drivers/tee/optee/optee_smc.h index 73b5e7760d10..7d9fa426505b 100644 --- a/drivers/tee/optee/optee_smc.h +++ b/drivers/tee/optee/optee_smc.h @@ -104,6 +104,30 @@ struct optee_smc_call_get_os_revision_result { unsigned long reserved1; }; +/* + * Load Trusted OS from optee/tee.bin in the Linux firmware. + * + * WARNING: Use this cautiously as it could lead to insecure loading of the + * Trusted OS. + * This SMC instructs EL3 to load a binary and execute it as the Trusted OS. + * + * Call register usage: + * a0 SMC Function ID, OPTEE_SMC_CALL_LOAD_IMAGE + * a1 Upper 32bit of a 64bit size for the payload + * a2 Lower 32bit of a 64bit size for the payload + * a3 Upper 32bit of the physical address for the payload + * a4 Lower 32bit of the physical address for the payload + * + * The payload is in the OP-TEE image format. + * + * Returns result in a0, 0 on success and an error code otherwise. + */ +#define OPTEE_SMC_FUNCID_LOAD_IMAGE 2 +#define OPTEE_SMC_CALL_LOAD_IMAGE \ + ARM_SMCCC_CALL_VAL(ARM_SMCCC_FAST_CALL, ARM_SMCCC_SMC_32, \ + ARM_SMCCC_OWNER_TRUSTED_OS_END, \ + OPTEE_SMC_FUNCID_LOAD_IMAGE) + /* * Call with struct optee_msg_arg as argument * diff --git a/drivers/tee/optee/smc_abi.c b/drivers/tee/optee/smc_abi.c index a1c1fa1a9c28..6e1f023d50c6 100644 --- a/drivers/tee/optee/smc_abi.c +++ b/drivers/tee/optee/smc_abi.c @@ -7,10 +7,13 @@ #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt #include <linux/arm-smccc.h> +#include <linux/cpuhotplug.h> #include <linux/errno.h> +#include <linux/firmware.h> #include <linux/interrupt.h> #include <linux/io.h> #include <linux/irqdomain.h> +#include <linux/kernel.h> #include <linux/mm.h> #include <linux/module.h> #include <linux/of.h> @@ -1149,6 +1152,22 @@ static bool optee_msg_api_uid_is_optee_api(optee_invoke_fn *invoke_fn) return false; } +#ifdef CONFIG_OPTEE_INSECURE_LOAD_IMAGE +static bool optee_msg_api_uid_is_optee_image_load(optee_invoke_fn *invoke_fn) +{ + struct arm_smccc_res res; + + invoke_fn(OPTEE_SMC_CALLS_UID, 0, 0, 0, 0, 0, 0, 0, &res); + + if (res.a0 == OPTEE_MSG_IMAGE_LOAD_UID_0 && + res.a1 == OPTEE_MSG_IMAGE_LOAD_UID_1 && + res.a2 == OPTEE_MSG_IMAGE_LOAD_UID_2 && + res.a3 == OPTEE_MSG_IMAGE_LOAD_UID_3) + return true; + return false; +} +#endif + static void optee_msg_get_os_revision(optee_invoke_fn *invoke_fn) { union { @@ -1354,6 +1373,120 @@ static void optee_shutdown(struct platform_device *pdev) optee_disable_shm_cache(optee); } +#ifdef CONFIG_OPTEE_INSECURE_LOAD_IMAGE + +#define OPTEE_FW_IMAGE "optee/tee.bin" + +static optee_invoke_fn *cpuhp_invoke_fn; + +static int optee_cpuhp_probe(unsigned int cpu) +{ + /* + * Invoking a call on a CPU will cause OP-TEE to perform the required + * setup for that CPU. Just invoke the call to get the UID since that + * has no side effects. + */ + if (optee_msg_api_uid_is_optee_api(cpuhp_invoke_fn)) + return 0; + else + return -EINVAL; +} + +static int optee_load_fw(struct platform_device *pdev, + optee_invoke_fn *invoke_fn) +{ + const struct firmware *fw = NULL; + struct arm_smccc_res res; + phys_addr_t data_pa; + u8 *data_buf = NULL; + u64 data_size; + u32 data_pa_high, data_pa_low; + u32 data_size_high, data_size_low; + int rc; + int hp_state; + + if (!optee_msg_api_uid_is_optee_image_load(invoke_fn)) + return 0; + + rc = request_firmware(&fw, OPTEE_FW_IMAGE, &pdev->dev); + if (rc) { + /* + * The firmware in the rootfs will not be accessible until we + * are in the SYSTEM_RUNNING state, so return EPROBE_DEFER until + * that point. + */ + if (system_state < SYSTEM_RUNNING) + return -EPROBE_DEFER; + goto fw_err; + } + + data_size = fw->size; + /* + * This uses the GFP_DMA flag to ensure we are allocated memory in the + * 32-bit space since TF-A cannot map memory beyond the 32-bit boundary. + */ + data_buf = kmalloc(fw->size, GFP_KERNEL | GFP_DMA); + if (!data_buf) { + rc = -ENOMEM; + goto fw_err; + } + memcpy(data_buf, fw->data, fw->size); + data_pa = virt_to_phys(data_buf); + reg_pair_from_64(&data_pa_high, &data_pa_low, data_pa); + reg_pair_from_64(&data_size_high, &data_size_low, data_size); + goto fw_load; + +fw_err: + pr_warn("image loading failed\n"); + data_pa_high = 0; + data_pa_low = 0; + data_size_high = 0; + data_size_low = 0; + +fw_load: + /* + * Always invoke the SMC, even if loading the image fails, to indicate + * to EL3 that we have passed the point where it should allow invoking + * this SMC. + */ + pr_warn("OP-TEE image loaded from kernel, this can be insecure"); + invoke_fn(OPTEE_SMC_CALL_LOAD_IMAGE, data_size_high, data_size_low, + data_pa_high, data_pa_low, 0, 0, 0, &res); + if (!rc) + rc = res.a0; + if (fw) + release_firmware(fw); + kfree(data_buf); + + if (!rc) { + /* + * We need to initialize OP-TEE on all other running cores as + * well. Any cores that aren't running yet will get initialized + * when they are brought up by the power management functions in + * TF-A which are registered by the OP-TEE SPD. Due to that we + * can un-register the callback right after registering it. + */ + cpuhp_invoke_fn = invoke_fn; + hp_state = cpuhp_setup_state(CPUHP_AP_ONLINE_DYN, "optee:probe", + optee_cpuhp_probe, NULL); + if (hp_state < 0) { + pr_warn("Failed with CPU hotplug setup for OP-TEE"); + return -EINVAL; + } + cpuhp_remove_state(hp_state); + cpuhp_invoke_fn = NULL; + } + + return rc; +} +#else +static inline int optee_load_fw(struct platform_device *pdev, + optee_invoke_fn *invoke_fn) +{ + return 0; +} +#endif + static int optee_probe(struct platform_device *pdev) { optee_invoke_fn *invoke_fn; @@ -1372,6 +1505,10 @@ static int optee_probe(struct platform_device *pdev) if (IS_ERR(invoke_fn)) return PTR_ERR(invoke_fn); + rc = optee_load_fw(pdev, invoke_fn); + if (rc) + return rc; + if (!optee_msg_api_uid_is_optee_api(invoke_fn)) { pr_warn("api uid mismatch\n"); return -EINVAL; -- 2.40.0.348.gf938b09366-goog

2 years, 8 months

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[GIT PULL] TEE fix for v6.3

by Jens Wiklander

Hello arm-soc maintainers, Please pull this small fix of a call to virt_to_page() in the TEE subsystem. Thanks, Jens The following changes since commit eeac8ede17557680855031c6f305ece2378af326: Linux 6.3-rc2 (2023-03-12 16:36:44 -0700) are available in the Git repository at: https://git.linaro.org/people/jens.wiklander/linux-tee.git/ tags/tee-fix-for-v6.3 for you to fetch changes up to 8671133082176d1388e20ac33d61cf7e3b05adf5: tee: Pass a pointer to virt_to_page() (2023-03-30 08:34:52 +0200) ---------------------------------------------------------------- Add explicit cast to (void *) for virt_to_page() argument ---------------------------------------------------------------- Linus Walleij (1): tee: Pass a pointer to virt_to_page() drivers/tee/tee_shm.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)

2 years, 8 months

1
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[PATCH] tee: Pass a pointer to virt_to_page()

by Linus Walleij

Like the other calls in this function virt_to_page() expects a pointer, not an integer. However since many architectures implement virt_to_pfn() as a macro, this function becomes polymorphic and accepts both a (unsigned long) and a (void *). Fix this up with an explicit cast. Signed-off-by: Linus Walleij <linus.walleij(a)linaro.org> --- drivers/tee/tee_shm.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/tee/tee_shm.c b/drivers/tee/tee_shm.c index b1c6231defad..673cf0359494 100644 --- a/drivers/tee/tee_shm.c +++ b/drivers/tee/tee_shm.c @@ -32,7 +32,7 @@ static int shm_get_kernel_pages(unsigned long start, size_t page_count, is_kmap_addr((void *)start))) return -EINVAL; - page = virt_to_page(start); + page = virt_to_page((void *)start); for (n = 0; n < page_count; n++) { pages[n] = page + n; get_page(pages[n]); -- 2.34.1

2 years, 8 months

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