diff options
| author | Kristina Martsenko <kristina.martsenko@arm.com> | 2020-03-13 14:34:56 +0530 |
|---|---|---|
| committer | Catalin Marinas <catalin.marinas@arm.com> | 2020-03-18 09:50:20 +0000 |
| commit | 33e45234987ea3ed4b05fc512f4441696478f12d (patch) | |
| tree | e7dbf5120c409f20c20d7b095dca1244ec3f3b85 /arch/arm64/mm/proc.S | |
| parent | 6982934e19f8ebb4152ba77308facdb1a38533f9 (diff) | |
arm64: initialize and switch ptrauth kernel keys
Set up keys to use pointer authentication within the kernel. The kernel
will be compiled with APIAKey instructions, the other keys are currently
unused. Each task is given its own APIAKey, which is initialized during
fork. The key is changed during context switch and on kernel entry from
EL0.
The keys for idle threads need to be set before calling any C functions,
because it is not possible to enter and exit a function with different
keys.
Reviewed-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Catalin Marinas <catalin.marinas@arm.com>
Reviewed-by: Vincenzo Frascino <Vincenzo.Frascino@arm.com>
Signed-off-by: Kristina Martsenko <kristina.martsenko@arm.com>
[Amit: Modified secondary cores key structure, comments]
Signed-off-by: Amit Daniel Kachhap <amit.kachhap@arm.com>
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
Diffstat (limited to 'arch/arm64/mm/proc.S')
| -rw-r--r-- | arch/arm64/mm/proc.S | 12 |
1 files changed, 12 insertions, 0 deletions
diff --git a/arch/arm64/mm/proc.S b/arch/arm64/mm/proc.S index 4cf19a26af2d..5a11a895e923 100644 --- a/arch/arm64/mm/proc.S +++ b/arch/arm64/mm/proc.S @@ -485,6 +485,10 @@ SYM_FUNC_START(__cpu_setup) ubfx x2, x2, #ID_AA64ISAR1_APA_SHIFT, #8 cbz x2, 3f + /* + * The primary cpu keys are reset here and can be + * re-initialised with some proper values later. + */ msr_s SYS_APIAKEYLO_EL1, xzr msr_s SYS_APIAKEYHI_EL1, xzr @@ -497,6 +501,14 @@ alternative_if_not ARM64_HAS_ADDRESS_AUTH b 3f alternative_else_nop_endif + /* Install ptrauth key for secondary cpus */ + adr_l x2, secondary_data + ldr x3, [x2, #CPU_BOOT_TASK] // get secondary_data.task + cbz x3, 2f // check for slow booting cpus + ldp x3, x4, [x2, #CPU_BOOT_PTRAUTH_KEY] + msr_s SYS_APIAKEYLO_EL1, x3 + msr_s SYS_APIAKEYHI_EL1, x4 + 2: /* Enable ptrauth instructions */ ldr x2, =SCTLR_ELx_ENIA | SCTLR_ELx_ENIB | \ SCTLR_ELx_ENDA | SCTLR_ELx_ENDB |