Commit Graph

5 Commits

Author SHA1 Message Date
Mark Brown
0c69bd2ca6 kselftest/arm64: pac: Fix skipping of tests on systems without PAC
The PAC tests check to see if the system supports the relevant PAC features
but instead of skipping the tests if they can't be executed they fail the
tests which makes things look like they're not working when they are.

Signed-off-by: Mark Brown <broonie@kernel.org>
Link: https://lore.kernel.org/r/20210819165723.43903-1-broonie@kernel.org
Signed-off-by: Catalin Marinas <catalin.marinas@arm.com>
2021-08-20 12:06:59 +01:00
Boyan Karatotev
d21435e967 kselftests/arm64: add PAuth tests for single threaded consistency and differently initialized keys
PAuth adds 5 different keys that can be used to sign addresses.

Add a test that verifies that the kernel initializes them to different
values and preserves them across context switches.

Signed-off-by: Boyan Karatotev <boyan.karatotev@arm.com>
Reviewed-by: Vincenzo Frascino <Vincenzo.Frascino@arm.com>
Reviewed-by: Amit Daniel Kachhap <amit.kachhap@arm.com>
Acked-by: Shuah Khan <skhan@linuxfoundation.org>
Cc: Shuah Khan <shuah@kernel.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will@kernel.org>
Link: https://lore.kernel.org/r/20200918104715.182310-5-boian4o1@gmail.com
Signed-off-by: Will Deacon <will@kernel.org>
2020-09-18 14:07:20 +01:00
Boyan Karatotev
806a15b254 kselftests/arm64: add PAuth test for whether exec() changes keys
Kernel documentation states that it will change PAuth keys on exec() calls.

Verify that all keys are correctly switched to new ones.

Signed-off-by: Boyan Karatotev <boyan.karatotev@arm.com>
Reviewed-by: Vincenzo Frascino <Vincenzo.Frascino@arm.com>
Reviewed-by: Amit Daniel Kachhap <amit.kachhap@arm.com>
Acked-by: Shuah Khan <skhan@linuxfoundation.org>
Cc: Shuah Khan <shuah@kernel.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will@kernel.org>
Link: https://lore.kernel.org/r/20200918104715.182310-4-boian4o1@gmail.com
Signed-off-by: Will Deacon <will@kernel.org>
2020-09-18 14:07:20 +01:00
Boyan Karatotev
766d95b1ed kselftests/arm64: add nop checks for PAuth tests
PAuth adds sign/verify controls to enable and disable groups of
instructions in hardware for compatibility with libraries that do not
implement PAuth. The kernel always enables them if it detects PAuth.

Add a test that checks that each group of instructions is enabled, if the
kernel reports PAuth as detected.

Note: For groups, for the purpose of this patch, we intend instructions
that use a certain key.

Signed-off-by: Boyan Karatotev <boyan.karatotev@arm.com>
Reviewed-by: Vincenzo Frascino <Vincenzo.Frascino@arm.com>
Reviewed-by: Amit Daniel Kachhap <amit.kachhap@arm.com>
Acked-by: Shuah Khan <skhan@linuxfoundation.org>
Cc: Shuah Khan <shuah@kernel.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will@kernel.org>
Link: https://lore.kernel.org/r/20200918104715.182310-3-boian4o1@gmail.com
Signed-off-by: Will Deacon <will@kernel.org>
2020-09-18 14:07:20 +01:00
Boyan Karatotev
e74e1d5572 kselftests/arm64: add a basic Pointer Authentication test
PAuth signs and verifies return addresses on the stack. It does so by
inserting a Pointer Authentication code (PAC) into some of the unused top
bits of an address. This is achieved by adding paciasp/autiasp instructions
at the beginning and end of a function.

This feature is partially backwards compatible with earlier versions of the
ARM architecture. To coerce the compiler into emitting fully backwards
compatible code the main file is compiled to target an earlier ARM version.
This allows the tests to check for the feature and print meaningful error
messages instead of crashing.

Add a test to verify that corrupting the return address results in a
SIGSEGV on return.

Signed-off-by: Boyan Karatotev <boyan.karatotev@arm.com>
Reviewed-by: Vincenzo Frascino <Vincenzo.Frascino@arm.com>
Reviewed-by: Amit Daniel Kachhap <amit.kachhap@arm.com>
Acked-by: Shuah Khan <skhan@linuxfoundation.org>
Cc: Shuah Khan <shuah@kernel.org>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Will Deacon <will@kernel.org>
Link: https://lore.kernel.org/r/20200918104715.182310-2-boian4o1@gmail.com
Signed-off-by: Will Deacon <will@kernel.org>
2020-09-18 14:07:20 +01:00