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2021-01-20efi_loader: Avoid emitting efi_var_buf to .GOTIlias Apalodimas1-1/+1
Atish reports that on RISC-V, accessing the EFI variables causes a kernel panic. An objdump of the file verifies that, since the global pointer for efi_var_buf ends up in .GOT section which is not mapped in virtual address space for Linux. <snip of efi_var_mem_find> 0000000000000084 <efi_var_mem_find>: 84: 715d addi sp,sp,-80 * objdump -dr 0000000000000086 <.LCFI2>: 86: e0a2 sd s0,64(sp) 88: fc26 sd s1,56(sp) 8a: e486 sd ra,72(sp) 8c: f84a sd s2,48(sp) 8e: f44e sd s3,40(sp) 90: f052 sd s4,32(sp) 92: ec56 sd s5,24(sp) 94: 00000497 auipc s1,0x0 94: R_RISCV_GOT_HI20 efi_var_buf 98: 0004b483 ld s1,0(s1) # 94 <.LCFI2+0xe> 98: R_RISCV_PCREL_LO12_I .L0 98: R_RISCV_RELAX *ABS* * objdump -t 0000000000000084 g F .text.efi_runtime 00000000000000b8 efi_var_mem_find With the patch applied: * objdump -dr 0000000000000086 <.LCFI2>: 86: e0a2 sd s0,64(sp) 88: fc26 sd s1,56(sp) 8a: e486 sd ra,72(sp) 8c: f84a sd s2,48(sp) 8e: f44e sd s3,40(sp) 90: f052 sd s4,32(sp) 92: ec56 sd s5,24(sp) 94: 00000497 auipc s1,0x0 94: R_RISCV_PCREL_HI20 .LANCHOR0 94: R_RISCV_RELAX *ABS* 98: 00048493 mv s1,s1 98: R_RISCV_PCREL_LO12_I .L0 98: R_RISCV_RELAX *ABS* * objdump -t 0000000000000008 l O .data.efi_runtime 0000000000000008 efi_var_buf On arm64 this works, because there's no .GOT entries for this and everything is converted to relative references. * objdump -dr (identical pre-post patch, only the new function shows up) 00000000000000b4 <efi_var_mem_find>: b4: aa0003ee mov x14, x0 b8: 9000000a adrp x10, 0 <efi_var_mem_compare> b8: R_AARCH64_ADR_PREL_PG_HI21 .data.efi_runtime bc: 91000140 add x0, x10, #0x0 bc: R_AARCH64_ADD_ABS_LO12_NC .data.efi_runtime c0: aa0103ed mov x13, x1 c4: 79400021 ldrh w1, [x1] c8: aa0203eb mov x11, x2 cc: f9400400 ldr x0, [x0, #8] d0: b940100c ldr w12, [x0, #16] d4: 8b0c000c add x12, x0, x12 So let's switch efi_var_buf to static and create a helper function for anyone that needs to update it. Fixes: e01aed47d6a0 ("efi_loader: Enable run-time variable support for tee based variables") Reported-by: Atish Patra <atishp@atishpatra.org> Tested-by: Atish Patra <atish.patra@wdc.com> Signed-off-by: Ilias Apalodimas <ilias.apalodimas@linaro.org> Reviewed-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
2020-12-26efi_loader: Extra checks while opening an OPTEE sessionIlias Apalodimas1-5/+15
When opening an OP-TEE session we need to check the internal return value of OP-TEE call arguments as well the return code of the function itself. The code was also ignoring to close the OP-TEE session in case the shared memory registration failed. Fixes: f042e47e8fb43 ("efi_loader: Implement EFI variable handling via OP-TEE") Signed-off-by: Ilias Apalodimas <ilias.apalodimas@linaro.org> Signed-off-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
2020-08-01efi_loader: Enable run-time variable support for tee based variablesIlias Apalodimas1-35/+47
We recently added functions for storing/restoring variables from a file to a memory backed buffer marked as __efi_runtime_data commit f1f990a8c958 ("efi_loader: memory buffer for variables") commit 5f7dcf079de8 ("efi_loader: UEFI variable persistence") Using the same idea we now can support GetVariable() and GetNextVariable() on the OP-TEE based variables as well. So let's re-arrange the code a bit and move the commmon code for accessing variables out of efi_variable.c. Create common functions for reading variables from memory that both implementations can use on run-time. Then just use those functions in the run-time variants of the OP-TEE based EFI variable implementation and initialize the memory buffer on ExitBootServices() Signed-off-by: Ilias Apalodimas <ilias.apalodimas@linaro.org> Reviewed-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
2020-08-01efi_loader: Trim output buffer size correctly for tee variablesIlias Apalodimas1-10/+3
The current code does not trim the output buffer correctly. In fact it doesn't trim the buffer at all, since it calculates a wrong value for it, which isn't even applied. So let's remove the unused temporary size variable and trim the buffer correctly. Since we are editing efi_get_next_variable_name_int(), fix an indentation error along the way. Fixes: f042e47e8fb43 ("efi_loader: Implement EFI variable handling via OP-TEE") Signed-off-by: Ilias Apalodimas <ilias.apalodimas@linaro.org> Remove superfluous conversion to (u8 *) for memcpy argument. Reviewed-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
2020-07-22efi_loader: Check for the native OP-TEE result on mm_communicate callsIlias Apalodimas1-2/+2
Currently we only check for the return value of tee_invoke_func(). Although OP-TEE and StMM will correctly set param[1].u.value.a and we'll eventually return an error, the correct thing to do is check for the OP_TEE return code as well. So let's check for that and move tee_shm_free() and tee_close_session() before exiting with an error to make sure we always clear the registered memory. Fixes: f042e47e8fb43 ("efi_loader: Implement EFI variable handling via OP-TEE") Signed-off-by: Ilias Apalodimas <ilias.apalodimas@linaro.org> Use EFI_DEVICE_ERROR for TEE communication problems. Reviewed-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
2020-07-22efi_loader: Rename and correct values for ARM_SMC_MM_*Ilias Apalodimas1-4/+4
Instead of adding the definition for the specific MM SVC used in StandAloneMM we added the one used in the standard SMC calls. So change the value from -4 to -5 to match the correct one defined in EDK2 and rename them to avoid future confusion Fixes 23a397d2e2fb: ("efi_loader: Add headers for EDK2 StandAloneMM communication") Signed-off-by: Ilias Apalodimas <ilias.apalodimas@linaro.org> Reviewed-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
2020-07-16efi_loader: update secure stateHeinrich Schuchardt1-0/+10
Update the UEFI secure state when variable 'PK' is updated in the TEE variables implementation. Signed-off-by: Heinrich Schuchardt <xypron.glpk@gmx.de> Reviewed-by: Ilias Apalodimas <ilias.apalodimas@linaro.org>
2020-07-16efi_loader: display RO attribute with TEE-backed variablesIlias Apalodimas1-6/+136
A previous commit adds support for displaying variables RO flag. Let's add it on the TEE backed variable storage as well. Signed-off-by: Ilias Apalodimas <ilias.apalodimas@linaro.org> Reviewed-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
2020-07-12efi_loader: separate UEFI variable API from implemementationHeinrich Schuchardt1-46/+9
Separate the remaining UEFI variable API functions GetNextVariableName and QueryVariableInfo() from internal functions implementing them. Signed-off-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
2020-07-12efi_loader: prepare for read only OP-TEE variablesHeinrich Schuchardt1-54/+21
We currently have two implementations of UEFI variables: * variables provided via an OP-TEE module * variables stored in the U-Boot environment Read only variables are up to now only implemented in the U-Boot environment implementation. Provide a common interface for both implementations that allows handling read-only variables. As variable access is limited to very few source files put variable related definitions into new include efi_variable.h instead of efi_loader. Signed-off-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
2020-07-12efi_loader: cleanup for tee backed variablesIlias Apalodimas1-5/+3
There's 2 variables in efi_get_next_variable_name() checking the size of the variable name. Let's get rid of the reduntant definition and simplitfy the code a bit. Signed-off-by: Ilias Apalodimas <ilias.apalodimas@linaro.org> Signed-off-by: Heinrich Schuchardt <xypron.glpk@gmx.de>
2020-05-17efi_loader: Implement EFI variable handling via OP-TEEIlias Apalodimas1-0/+662
In OP-TEE we can run EDK2's StandAloneMM on a secure partition. StandAloneMM is responsible for the UEFI variable support. In combination with OP-TEE and it's U-Boot supplicant, variables are authenticated/validated in secure world and stored on an RPMB partition. So let's add a new config option in U-Boot implementing the necessary calls to OP-TEE for the variable management. Signed-off-by: Ilias Apalodimas <ilias.apalodimas@linaro.org> Signed-off-by: Pipat Methavanitpong <pipat1010@gmail.com> Signed-off-by: Sughosh Ganu <sughosh.ganu@linaro.org> Reviewed-by: Heinrich Schuchardt <xypron.glpk@gmx.de>