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| author | Reinette Chatre <reinette.chatre@intel.com> | 2022-05-10 11:08:47 -0700 |
|---|---|---|
| committer | Dave Hansen <dave.hansen@linux.intel.com> | 2022-07-07 10:13:02 -0700 |
| commit | 8cb7b502f31e6cc4c6ebe2c5eeaa90dcab418cf1 (patch) | |
| tree | 844115367689621a8eac16de73c22eb7d2ade550 | |
| parent | dda03e2c331b9fc7bbc8fc0de12a6d92d8c18661 (diff) | |
| download | linux-8cb7b502f31e6cc4c6ebe2c5eeaa90dcab418cf1.tar.gz linux-8cb7b502f31e6cc4c6ebe2c5eeaa90dcab418cf1.tar.bz2 linux-8cb7b502f31e6cc4c6ebe2c5eeaa90dcab418cf1.zip | |
x86/sgx: Keep record of SGX page type
SGX2 functions are not allowed on all page types. For example,
ENCLS[EMODPR] is only allowed on regular SGX enclave pages and
ENCLS[EMODPT] is only allowed on TCS and regular pages. If these
functions are attempted on another type of page the hardware would
trigger a fault.
Keep a record of the SGX page type so that there is more
certainty whether an SGX2 instruction can succeed and faults
can be treated as real failures.
The page type is a property of struct sgx_encl_page
and thus does not cover the VA page type. VA pages are maintained
in separate structures and their type can be determined in
a different way. The SGX2 instructions needing the page type do not
operate on VA pages and this is thus not a scenario needing to
be covered at this time.
struct sgx_encl_page hosting this information is maintained for each
enclave page so the space consumed by the struct is important.
The existing sgx_encl_page->vm_max_prot_bits is already unsigned long
while only using three bits. Transition to a bitfield for the two
members to support the additional information without increasing
the space consumed by the struct.
Signed-off-by: Reinette Chatre <reinette.chatre@intel.com>
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Reviewed-by: Jarkko Sakkinen <jarkko@kernel.org>
Link: https://lkml.kernel.org/r/a0a6939eefe7ba26514f6c49723521cde372de64.1652137848.git.reinette.chatre@intel.com
| -rw-r--r-- | arch/x86/include/asm/sgx.h | 3 | ||||
| -rw-r--r-- | arch/x86/kernel/cpu/sgx/encl.h | 3 | ||||
| -rw-r--r-- | arch/x86/kernel/cpu/sgx/ioctl.c | 2 |
3 files changed, 7 insertions, 1 deletions
diff --git a/arch/x86/include/asm/sgx.h b/arch/x86/include/asm/sgx.h index d67810b50a81..eae20fa52b93 100644 --- a/arch/x86/include/asm/sgx.h +++ b/arch/x86/include/asm/sgx.h @@ -239,6 +239,9 @@ struct sgx_pageinfo { * %SGX_PAGE_TYPE_REG: a regular page * %SGX_PAGE_TYPE_VA: a VA page * %SGX_PAGE_TYPE_TRIM: a page in trimmed state + * + * Make sure when making changes to this enum that its values can still fit + * in the bitfield within &struct sgx_encl_page */ enum sgx_page_type { SGX_PAGE_TYPE_SECS, diff --git a/arch/x86/kernel/cpu/sgx/encl.h b/arch/x86/kernel/cpu/sgx/encl.h index f72a674e2605..799d4cdb12d5 100644 --- a/arch/x86/kernel/cpu/sgx/encl.h +++ b/arch/x86/kernel/cpu/sgx/encl.h @@ -27,7 +27,8 @@ struct sgx_encl_page { unsigned long desc; - unsigned long vm_max_prot_bits; + unsigned long vm_max_prot_bits:8; + enum sgx_page_type type:16; struct sgx_epc_page *epc_page; struct sgx_encl *encl; struct sgx_va_page *va_page; diff --git a/arch/x86/kernel/cpu/sgx/ioctl.c b/arch/x86/kernel/cpu/sgx/ioctl.c index a66795e0b685..21078c6643f7 100644 --- a/arch/x86/kernel/cpu/sgx/ioctl.c +++ b/arch/x86/kernel/cpu/sgx/ioctl.c @@ -107,6 +107,7 @@ static int sgx_encl_create(struct sgx_encl *encl, struct sgx_secs *secs) set_bit(SGX_ENCL_DEBUG, &encl->flags); encl->secs.encl = encl; + encl->secs.type = SGX_PAGE_TYPE_SECS; encl->base = secs->base; encl->size = secs->size; encl->attributes = secs->attributes; @@ -344,6 +345,7 @@ static int sgx_encl_add_page(struct sgx_encl *encl, unsigned long src, */ encl_page->encl = encl; encl_page->epc_page = epc_page; + encl_page->type = (secinfo->flags & SGX_SECINFO_PAGE_TYPE_MASK) >> 8; encl->secs_child_cnt++; if (flags & SGX_PAGE_MEASURE) { |