From 73916b6a0c714258f9c2619408a66c6696a761a7 Mon Sep 17 00:00:00 2001 From: Kai Huang Date: Fri, 19 Mar 2021 20:23:07 +1300 Subject: x86/sgx: Add helper to update SGX_LEPUBKEYHASHn MSRs Add a helper to update SGX_LEPUBKEYHASHn MSRs. SGX virtualization also needs to update those MSRs based on guest's "virtual" SGX_LEPUBKEYHASHn before EINIT from guest. Signed-off-by: Kai Huang Signed-off-by: Borislav Petkov Acked-by: Dave Hansen Acked-by: Jarkko Sakkinen Link: https://lkml.kernel.org/r/dfb7cd39d4dd62ea27703b64afdd8bccb579f623.1616136308.git.kai.huang@intel.com --- arch/x86/kernel/cpu/sgx/ioctl.c | 5 ++--- arch/x86/kernel/cpu/sgx/main.c | 16 ++++++++++++++++ arch/x86/kernel/cpu/sgx/sgx.h | 2 ++ 3 files changed, 20 insertions(+), 3 deletions(-) (limited to 'arch/x86/kernel') diff --git a/arch/x86/kernel/cpu/sgx/ioctl.c b/arch/x86/kernel/cpu/sgx/ioctl.c index 11e3f9635c24..7be9c064a640 100644 --- a/arch/x86/kernel/cpu/sgx/ioctl.c +++ b/arch/x86/kernel/cpu/sgx/ioctl.c @@ -495,7 +495,7 @@ static int sgx_encl_init(struct sgx_encl *encl, struct sgx_sigstruct *sigstruct, void *token) { u64 mrsigner[4]; - int i, j, k; + int i, j; void *addr; int ret; @@ -544,8 +544,7 @@ static int sgx_encl_init(struct sgx_encl *encl, struct sgx_sigstruct *sigstruct, preempt_disable(); - for (k = 0; k < 4; k++) - wrmsrl(MSR_IA32_SGXLEPUBKEYHASH0 + k, mrsigner[k]); + sgx_update_lepubkeyhash(mrsigner); ret = __einit(sigstruct, token, addr); diff --git a/arch/x86/kernel/cpu/sgx/main.c b/arch/x86/kernel/cpu/sgx/main.c index 1c8a228b0104..227f1e2ad9cf 100644 --- a/arch/x86/kernel/cpu/sgx/main.c +++ b/arch/x86/kernel/cpu/sgx/main.c @@ -727,6 +727,22 @@ static bool __init sgx_page_cache_init(void) return true; } +/* + * Update the SGX_LEPUBKEYHASH MSRs to the values specified by caller. + * Bare-metal driver requires to update them to hash of enclave's signer + * before EINIT. KVM needs to update them to guest's virtual MSR values + * before doing EINIT from guest. + */ +void sgx_update_lepubkeyhash(u64 *lepubkeyhash) +{ + int i; + + WARN_ON_ONCE(preemptible()); + + for (i = 0; i < 4; i++) + wrmsrl(MSR_IA32_SGXLEPUBKEYHASH0 + i, lepubkeyhash[i]); +} + static int __init sgx_init(void) { int ret; diff --git a/arch/x86/kernel/cpu/sgx/sgx.h b/arch/x86/kernel/cpu/sgx/sgx.h index e4cbc71bf136..4628acec0009 100644 --- a/arch/x86/kernel/cpu/sgx/sgx.h +++ b/arch/x86/kernel/cpu/sgx/sgx.h @@ -93,4 +93,6 @@ static inline int __init sgx_vepc_init(void) } #endif +void sgx_update_lepubkeyhash(u64 *lepubkeyhash); + #endif /* _X86_SGX_H */ -- cgit v1.2.3