February 2023 - OP-TEE - lists.trustedfirmware.org

[PATCH v3 0/3] introduce tee-based EFI Runtime Variable Service

by Masahisa Kojima

This series introduces the tee based EFI Runtime Variable Service. The eMMC device is typically owned by the non-secure world(linux in this case). There is an existing solution utilizing eMMC RPMB partition for EFI Variables, it is implemented by interacting with OP-TEE, StandaloneMM(as EFI Variable Service Pseudo TA), eMMC driver and tee-supplicant. The last piece is the tee-based variable access driver to interact with OP-TEE and StandaloneMM. Changelog: v2 -> v3: - add CONFIG_EFI dependency to TEE_STMM_EFI - add missing return code check for tee_client_invoke_func() - directly call efivars_register/unregister from tee_stmm_efi.c rfc v1 -> v2: - split patch into three patches, one for drivers/tee, one for include/linux/efi.h, and one for the driver/firmware/efi/stmm - context/session management into probe() and remove() same as other tee client driver - StMM variable driver is moved from driver/tee/optee to driver/firmware/efi - use "tee" prefix instead of "optee" in driver/firmware/efi/stmm/tee_stmm_efi.c, this file does not contain op-tee specific code, abstracted by tee layer and StMM variable driver will work on other tee implementation. - PTA_STMM_CMD_COMMUNICATE -> PTA_STMM_CMD_COMMUNICATE - implement query_variable_store() but currently not used - no use of TEEC_SUCCESS, it is defined in driver/tee/optee/optee_private.h. Other tee client drivers use 0 instead of using TEEC_SUCCESS - remove TEEC_ERROR_EXCESS_DATA status, it is refered just to output error message Masahisa Kojima (3): efi: expose efivar generic ops register function efi: Add EFI_ACCESS_DENIED status code efi: Add tee-based EFI variable driver drivers/firmware/efi/Kconfig | 15 + drivers/firmware/efi/Makefile | 1 + drivers/firmware/efi/efi.c | 12 + drivers/firmware/efi/stmm/mm_communication.h | 249 ++++++++ drivers/firmware/efi/stmm/tee_stmm_efi.c | 626 +++++++++++++++++++ include/linux/efi.h | 4 + 6 files changed, 907 insertions(+) create mode 100644 drivers/firmware/efi/stmm/mm_communication.h create mode 100644 drivers/firmware/efi/stmm/tee_stmm_efi.c -- 2.30.2

1 year, 6 months

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[PATCH] tee: optee: Fix typo Unuspported -> Unsupported

by Jules Maselbas

Fix typo Unuspported -> Unsupported Signed-off-by: Jules Maselbas <jmaselbas(a)kalray.eu> --- drivers/tee/optee/call.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/tee/optee/call.c b/drivers/tee/optee/call.c index 290b1bb0e9cd..df5fb5410b72 100644 --- a/drivers/tee/optee/call.c +++ b/drivers/tee/optee/call.c @@ -488,7 +488,7 @@ static bool is_normal_memory(pgprot_t p) #elif defined(CONFIG_ARM64) return (pgprot_val(p) & PTE_ATTRINDX_MASK) == PTE_ATTRINDX(MT_NORMAL); #else -#error "Unuspported architecture" +#error "Unsupported architecture" #endif } -- 2.17.1

1 year, 8 months

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Post-boot loading of OP-TEE

by Jens Wiklander

Hi, The recent patch [1] for the OP-TEE Dispatcher in TF-A proposes a way of post-boot loading OP-TEE by the Linux kernel with signature verification in the normal world only. This has previously been discussed in this mail thread [2] about half a year ago. Ultimately, it was concluded that this should in principle be accepted upstream as a platform choice to allow this or not. There are concerns that what we have in upstream TF-A should serve as good examples, and trusting the normal world to verify secure world software might not meet that criterion. There are also concerns about adding signature verification to BL31 Leaving the secure world wide open until the Linux kernel has been able to successfully load and verify an OP-TEE binary seems very risky. Even if it's claimed that the normal world can be trusted at this point, we're still giving up a critical level of defense without a good reason. I've started to review [1], but it should not be accepted for merging without support and approval from other maintainers. I would like to explore other options in this mail thread. In [2] it was suggested that a remnant of bl2 could be kept to verify OP-TEE before starting to execute it. This could be taken one step further and load a limited OP-TEE at boot which later is updated live, almost like what's discussed in [3]. This should minimize the impact on TF-A and also leave OP-TEE in charge of accepting an update instead of a divided responsibility between the normal world and TF-A. [1] https://review.trustedfirmware.org/c/TF-A/trusted-firmware-a/+/18635 [2] https://lists.trustedfirmware.org/archives/list/tf-a@lists.trustedfirmware.… [3] https://github.com/OP-TEE/optee_os/issues/5699 Thanks, Jens

1 year, 8 months

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[PATCH] 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 ARM that supports this. Signed-off-by: Jeffrey Kardatzke <jkardatzke(a)chromium.org> Signed-off-by: Jeffrey Kardatzke <jkardatzke(a)google.com> --- drivers/tee/optee/Kconfig | 10 +++++ drivers/tee/optee/optee_msg.h | 14 +++++++ drivers/tee/optee/optee_smc.h | 22 ++++++++++ drivers/tee/optee/smc_abi.c | 77 +++++++++++++++++++++++++++++++++++ 4 files changed, 123 insertions(+) diff --git a/drivers/tee/optee/Kconfig b/drivers/tee/optee/Kconfig index f121c224e682..5ffbeb3eaac0 100644 --- a/drivers/tee/optee/Kconfig +++ b/drivers/tee/optee/Kconfig @@ -7,3 +7,13 @@ config OPTEE help This implements the OP-TEE Trusted Execution Environment (TEE) driver. + +config OPTEE_LOAD_IMAGE + bool "Load Op-Tee image as firmware" + default n + depends on OPTEE + 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. diff --git a/drivers/tee/optee/optee_msg.h b/drivers/tee/optee/optee_msg.h index 70e9cc2ee96b..84c1b15032a9 100644 --- a/drivers/tee/optee/optee_msg.h +++ b/drivers/tee/optee/optee_msg.h @@ -284,6 +284,20 @@ struct optee_msg_arg { */ #define OPTEE_MSG_FUNCID_GET_OS_REVISION 0x0001 +/* + * 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 excute it as the Trusted OS. + * The first two params are the high and low 32 bits of the size of the payload + * and the third and fourth params are the high and low 32 bits of the physical + * address of the payload. The payload is in the OP-TEE image format. + * + * Returns 0 on success and an error code otherwise. + */ +#define OPTEE_MSG_FUNCID_LOAD_IMAGE 0x0002 + /* * Do a secure call with struct optee_msg_arg as argument * The OPTEE_MSG_CMD_* below defines what goes in struct optee_msg_arg::cmd diff --git a/drivers/tee/optee/optee_smc.h b/drivers/tee/optee/optee_smc.h index 73b5e7760d10..908b1005e9db 100644 --- a/drivers/tee/optee/optee_smc.h +++ b/drivers/tee/optee/optee_smc.h @@ -104,6 +104,28 @@ 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 excute 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 OPTEE_MSG_FUNCID_LOAD_IMAGE +#define OPTEE_SMC_CALL_LOAD_IMAGE \ + OPTEE_SMC_FAST_CALL_VAL(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..c1abbee86b39 100644 --- a/drivers/tee/optee/smc_abi.c +++ b/drivers/tee/optee/smc_abi.c @@ -8,9 +8,11 @@ #include <linux/arm-smccc.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> @@ -1354,6 +1356,77 @@ static void optee_shutdown(struct platform_device *pdev) optee_disable_shm_cache(optee); } +#ifdef CONFIG_OPTEE_LOAD_IMAGE + +#define OPTEE_FW_IMAGE "optee/tee.bin" + +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; + + 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 = data_pa_low = data_size_high = 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. + */ + 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); + + return rc; +} +#else +static inline int optee_load_fw(struct platform_device *__unused, + optee_invoke_fn *__unused) { + return 0; +} +#endif + static int optee_probe(struct platform_device *pdev) { optee_invoke_fn *invoke_fn; @@ -1372,6 +1445,10 @@ 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; -- 2.39.2.637.g21b0678d19-goog

1 year, 8 months

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[GIT PULL] Fix race condition in AMDTEE driver

by Jens Wiklander

Hello arm-soc maintainers, Please pull this fix for the AMDTEE driver in the TEE subsystem. Note that this isn't a usual Arm driver update. This targets AMD instead, but is part of the TEE subsystem. Thanks, Jens The following changes since commit c9c3395d5e3dcc6daee66c6908354d47bf98cb0c: Linux 6.2 (2023-02-19 14:24:22 -0800) are available in the Git repository at: https://git.linaro.org/people/jens.wiklander/linux-tee.git/ tags/amdtee-fix-for-v6.3 for you to fetch changes up to f8502fba45bd30e1a6a354d9d898bc99d1a11e6d: tee: amdtee: fix race condition in amdtee_open_session (2023-02-28 18:39:19 +0100) ---------------------------------------------------------------- AMDTEE fix race condition in amdtee_open_session() ---------------------------------------------------------------- Rijo Thomas (1): tee: amdtee: fix race condition in amdtee_open_session drivers/tee/amdtee/core.c | 29 ++++++++++++++--------------- 1 file changed, 14 insertions(+), 15 deletions(-)

1 year, 8 months

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[PATCH 1/1] tee: amdtee: fix race condition in amdtee_open_session

by Rijo Thomas

There is a potential race condition in amdtee_open_session that may lead to use-after-free. For instance, in amdtee_open_session() after sess->sess_mask is set, and before setting: sess->session_info[i] = session_info; if amdtee_close_session() closes this same session, then 'sess' data structure will be released, causing kernel panic when 'sess' is accessed within amdtee_open_session(). The solution is to set the bit sess->sess_mask as the last step in amdtee_open_session(). Fixes: 757cc3e9ff1d ("tee: add AMD-TEE driver") Cc: stable(a)vger.kernel.org Signed-off-by: Rijo Thomas <Rijo-john.Thomas(a)amd.com> --- drivers/tee/amdtee/core.c | 29 ++++++++++++++--------------- 1 file changed, 14 insertions(+), 15 deletions(-) diff --git a/drivers/tee/amdtee/core.c b/drivers/tee/amdtee/core.c index 297dc62bca29..372d64756ed6 100644 --- a/drivers/tee/amdtee/core.c +++ b/drivers/tee/amdtee/core.c @@ -267,35 +267,34 @@ int amdtee_open_session(struct tee_context *ctx, goto out; } + /* Open session with loaded TA */ + handle_open_session(arg, &session_info, param); + if (arg->ret != TEEC_SUCCESS) { + pr_err("open_session failed %d\n", arg->ret); + handle_unload_ta(ta_handle); + kref_put(&sess->refcount, destroy_session); + goto out; + } + /* Find an empty session index for the given TA */ spin_lock(&sess->lock); i = find_first_zero_bit(sess->sess_mask, TEE_NUM_SESSIONS); - if (i < TEE_NUM_SESSIONS) + if (i < TEE_NUM_SESSIONS) { + sess->session_info[i] = session_info; + set_session_id(ta_handle, i, &arg->session); set_bit(i, sess->sess_mask); + } spin_unlock(&sess->lock); if (i >= TEE_NUM_SESSIONS) { pr_err("reached maximum session count %d\n", TEE_NUM_SESSIONS); + handle_close_session(ta_handle, session_info); handle_unload_ta(ta_handle); kref_put(&sess->refcount, destroy_session); rc = -ENOMEM; goto out; } - /* Open session with loaded TA */ - handle_open_session(arg, &session_info, param); - if (arg->ret != TEEC_SUCCESS) { - pr_err("open_session failed %d\n", arg->ret); - spin_lock(&sess->lock); - clear_bit(i, sess->sess_mask); - spin_unlock(&sess->lock); - handle_unload_ta(ta_handle); - kref_put(&sess->refcount, destroy_session); - goto out; - } - - sess->session_info[i] = session_info; - set_session_id(ta_handle, i, &arg->session); out: free_pages((u64)ta, get_order(ta_size)); return rc; -- 2.25.1

1 year, 8 months

2
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Hafnium Dynamic Shared Memory

by 梅建强(禹夜)

Hi, experts Here are the comments I saw in the Hafnium code. /* * Hafnium doesn't support fragmentation of memory retrieve requests * (because it doesn't support caller-specified mappings, so a request * will never be larger than a single page), so this must be part of a * memory send (i.e. donate, lend or share) request. * * We can tell from the handle whether the memory transaction is for the * TEE or not. */ I have a few questions about this description. 1. In the case of Hafnium as SPMC, optee should register memory fragments allocated by linux. What does Hafnium do with these memory fragments since doesn't support fragmentation of memory retrieve requests? 2. How does Hafnium map the page tables of stage-2 in dynamic shared memory for CA/TA, and are these page tables stored in the heap, or where? 3. What does HF_MAILBOX for dynamic shared memory mean? How does it relate to RX/TX buffer? Where can I see the related introduction in detail? Regards, Yuye

1 year, 8 months

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Linaro OP-TEE Contribution (LOC) monthly meeting February 28

by Jens Wiklander

Hi, It's soon time for another LOC monthly meeting. For time and connection details see the calendar at https://www.trustedfirmware.org/meetings/ I have recently seen interest in OP-TEE and S-EL2. As you may know, we have a working setup with OP-TEE and Hafnium with most of the needed patches upstream. Any other topics? Thanks, Jens

1 year, 8 months

2
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[PATCH v2] 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 ARM that supports this. Signed-off-by: Jeffrey Kardatzke <jkardatzke(a)chromium.org> Signed-off-by: Jeffrey Kardatzke <jkardatzke(a)google.com> --- Changes in v2: - Fixed compile issue when feature is disabled - Addressed minor comments - Added state tracking for driver reload drivers/tee/optee/Kconfig | 10 +++++ drivers/tee/optee/optee_smc.h | 22 ++++++++++ drivers/tee/optee/smc_abi.c | 82 +++++++++++++++++++++++++++++++++++ 3 files changed, 114 insertions(+) diff --git a/drivers/tee/optee/Kconfig b/drivers/tee/optee/Kconfig index f121c224e682..f0f12b146add 100644 --- a/drivers/tee/optee/Kconfig +++ b/drivers/tee/optee/Kconfig @@ -7,3 +7,13 @@ config OPTEE help This implements the OP-TEE Trusted Execution Environment (TEE) driver. + +config OPTEE_LOAD_IMAGE + bool "Load OP-TEE image as firmware" + default n + depends on OPTEE + 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. diff --git a/drivers/tee/optee/optee_smc.h b/drivers/tee/optee/optee_smc.h index 73b5e7760d10..a24c524b44fa 100644 --- a/drivers/tee/optee/optee_smc.h +++ b/drivers/tee/optee/optee_smc.h @@ -104,6 +104,28 @@ 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 \ + OPTEE_SMC_FAST_CALL_VAL(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..79ddfb0f9aca 100644 --- a/drivers/tee/optee/smc_abi.c +++ b/drivers/tee/optee/smc_abi.c @@ -8,9 +8,11 @@ #include <linux/arm-smccc.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> @@ -1354,6 +1356,82 @@ static void optee_shutdown(struct platform_device *pdev) optee_disable_shm_cache(optee); } +#ifdef CONFIG_OPTEE_LOAD_IMAGE + +#define OPTEE_FW_IMAGE "optee/tee.bin" + +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; + static int rc; + static bool already_loaded; + + if (already_loaded) + return rc; + + 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 = data_pa_low = data_size_high = 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. + */ + 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); + already_loaded = true; + + return rc; +} +#else +static inline int optee_load_fw(struct platform_device *__unused1, + optee_invoke_fn *__unused2) { + return 0; +} +#endif + static int optee_probe(struct platform_device *pdev) { optee_invoke_fn *invoke_fn; @@ -1372,6 +1450,10 @@ 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; -- 2.39.2.637.g21b0678d19-goog

1 year, 9 months

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

by Jeffrey Kardatzke

This is the kernel patch corresponding to the change landed in TF-A here: https://review.trustedfirmware.org/c/TF-A/trusted-firmware-a/+/18635 This appears to be the right place to post this, let me know if not please. From 81d97a06a48d01eb53661b41905768271f07b870 Mon Sep 17 00:00:00 2001 From: Jeffrey Kardatzke <jkardatzke(a)google.com> Date: Fri, 3 Feb 2023 11:33:17 -0800 Subject: [PATCH] tee: optee: Add SMC for loading OP-TEE image 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 ARM that supports this. Signed-off-by: Jeffrey Kardatzke <jkardatzke(a)google.com> --- drivers/tee/optee/Kconfig | 9 +++++ drivers/tee/optee/optee_msg.h | 14 +++++++ drivers/tee/optee/optee_smc.h | 22 +++++++++++ drivers/tee/optee/smc_abi.c | 70 +++++++++++++++++++++++++++++++++++ 4 files changed, 115 insertions(+) diff --git a/drivers/tee/optee/Kconfig b/drivers/tee/optee/Kconfig index f121c224e682..b96b5db52b37 100644 --- a/drivers/tee/optee/Kconfig +++ b/drivers/tee/optee/Kconfig @@ -7,3 +7,12 @@ config OPTEE help This implements the OP-TEE Trusted Execution Environment (TEE) driver. + +config OPTEE_LOAD_IMAGE + bool "Load Op-Tee image as firmware" + default n + depends on OPTEE + 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. diff --git a/drivers/tee/optee/optee_msg.h b/drivers/tee/optee/optee_msg.h index 70e9cc2ee96b..84c1b15032a9 100644 --- a/drivers/tee/optee/optee_msg.h +++ b/drivers/tee/optee/optee_msg.h @@ -284,6 +284,20 @@ struct optee_msg_arg { */ #define OPTEE_MSG_FUNCID_GET_OS_REVISION 0x0001 +/* + * 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 excute it as the Trusted OS. + * The first two params are the high and low 32 bits of the size of the payload + * and the third and fourth params are the high and low 32 bits of the physical + * address of the payload. The payload is in the OP-TEE image format. + * + * Returns 0 on success and an error code otherwise. + */ +#define OPTEE_MSG_FUNCID_LOAD_IMAGE 0x0002 + /* * Do a secure call with struct optee_msg_arg as argument * The OPTEE_MSG_CMD_* below defines what goes in struct optee_msg_arg::cmd diff --git a/drivers/tee/optee/optee_smc.h b/drivers/tee/optee/optee_smc.h index 73b5e7760d10..908b1005e9db 100644 --- a/drivers/tee/optee/optee_smc.h +++ b/drivers/tee/optee/optee_smc.h @@ -104,6 +104,28 @@ 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 excute 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 OPTEE_MSG_FUNCID_LOAD_IMAGE +#define OPTEE_SMC_CALL_LOAD_IMAGE \ + OPTEE_SMC_FAST_CALL_VAL(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..b1e6c4a807db 100644 --- a/drivers/tee/optee/smc_abi.c +++ b/drivers/tee/optee/smc_abi.c @@ -8,6 +8,7 @@ #include <linux/arm-smccc.h> #include <linux/errno.h> +#include <linux/firmware.h> #include <linux/interrupt.h> #include <linux/io.h> #include <linux/irqdomain.h> @@ -1354,6 +1355,69 @@ static void optee_shutdown(struct platform_device *pdev) optee_disable_shm_cache(optee); } +#ifdef CONFIG_OPTEE_LOAD_IMAGE + +#define OPTEE_FW_IMAGE "optee/tee.bin" + +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; + + rc = request_firmware(&fw, OPTEE_FW_IMAGE, &pdev->dev); + if (rc) + return -EPROBE_DEFER; + + 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 = data_pa_low = data_size_high = 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. + */ + 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); + + return rc; +} +#else +static inline int optee_load_fw(struct platform_device *__unused, + optee_invoke_fn *__unused) { + return 0; +} +#endif + static int optee_probe(struct platform_device *pdev) { optee_invoke_fn *invoke_fn; @@ -1372,6 +1436,12 @@ 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) { + pr_warn("image loading failed\n"); + return rc; + } + if (!optee_msg_api_uid_is_optee_api(invoke_fn)) { pr_warn("api uid mismatch\n"); return -EINVAL; -- 2.39.1.519.gcb327c4b5f-goog

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OP-TEE February 2023