| Message ID | 20200828131606.7946-3-boyan.karatotev@arm.com (mailing list archive) |
|---|---|
| State | New |
| Headers | show |
| Series | kselftests/arm64: add PAuth tests | expand |
On 8/28/20 2:16 PM, Boyan Karatotev wrote: > 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. > Reviewed-by: Vincenzo Frascino <Vincenzo.Frascino@arm.com> > Cc: Shuah Khan <shuah@kernel.org> > Cc: Catalin Marinas <catalin.marinas@arm.com> > Cc: Will Deacon <will@kernel.org> > Signed-off-by: Boyan Karatotev <boyan.karatotev@arm.com> > --- > .../testing/selftests/arm64/pauth/.gitignore | 1 + > tools/testing/selftests/arm64/pauth/Makefile | 7 ++- > tools/testing/selftests/arm64/pauth/helper.c | 41 +++++++++++++++ > tools/testing/selftests/arm64/pauth/helper.h | 10 ++++ > tools/testing/selftests/arm64/pauth/pac.c | 51 +++++++++++++++++++ > 5 files changed, 108 insertions(+), 2 deletions(-) > create mode 100644 tools/testing/selftests/arm64/pauth/helper.c > > diff --git a/tools/testing/selftests/arm64/pauth/.gitignore b/tools/testing/selftests/arm64/pauth/.gitignore > index b557c916720a..155137d92722 100644 > --- a/tools/testing/selftests/arm64/pauth/.gitignore > +++ b/tools/testing/selftests/arm64/pauth/.gitignore > @@ -1 +1,2 @@ > +exec_target > pac > diff --git a/tools/testing/selftests/arm64/pauth/Makefile b/tools/testing/selftests/arm64/pauth/Makefile > index 785c775e5e41..a017d1c8dd58 100644 > --- a/tools/testing/selftests/arm64/pauth/Makefile > +++ b/tools/testing/selftests/arm64/pauth/Makefile > @@ -4,7 +4,7 @@ > CFLAGS += -mbranch-protection=pac-ret > > TEST_GEN_PROGS := pac > -TEST_GEN_FILES := pac_corruptor.o > +TEST_GEN_FILES := pac_corruptor.o helper.o > > include ../../lib.mk > > @@ -13,10 +13,13 @@ include ../../lib.mk > $(OUTPUT)/pac_corruptor.o: pac_corruptor.S > $(CC) -c $^ -o $@ $(CFLAGS) -march=armv8.3-a > > +$(OUTPUT)/helper.o: helper.c > + $(CC) -c $^ -o $@ $(CFLAGS) -march=armv8.3-a > + > # when -mbranch-protection is enabled and the target architecture is ARMv8.3 or > # greater, gcc emits pac* instructions which are not in HINT NOP space, > # preventing the tests from occurring at all. Compile for ARMv8.2 so tests can > # run on earlier targets and print a meaningful error messages > -$(OUTPUT)/pac: pac.c $(OUTPUT)/pac_corruptor.o > +$(OUTPUT)/pac: pac.c $(OUTPUT)/pac_corruptor.o $(OUTPUT)/helper.o > $(CC) $^ -o $@ $(CFLAGS) -march=armv8.2-a > > diff --git a/tools/testing/selftests/arm64/pauth/helper.c b/tools/testing/selftests/arm64/pauth/helper.c > new file mode 100644 > index 000000000000..8619afb16124 > --- /dev/null > +++ b/tools/testing/selftests/arm64/pauth/helper.c > @@ -0,0 +1,41 @@ > +// SPDX-License-Identifier: GPL-2.0 > +// Copyright (C) 2020 ARM Limited > + > +#include "helper.h" > + > + > +size_t keyia_sign(size_t ptr) > +{ > + asm volatile("paciza %0" : "+r" (ptr)); > + return ptr; > +} > + > +size_t keyib_sign(size_t ptr) > +{ > + asm volatile("pacizb %0" : "+r" (ptr)); > + return ptr; > +} > + > +size_t keyda_sign(size_t ptr) > +{ > + asm volatile("pacdza %0" : "+r" (ptr)); > + return ptr; > +} > + > +size_t keydb_sign(size_t ptr) > +{ > + asm volatile("pacdzb %0" : "+r" (ptr)); > + return ptr; > +} > + > +size_t keyg_sign(size_t ptr) > +{ > + /* output is encoded in the upper 32 bits */ > + size_t dest = 0; > + size_t modifier = 0; > + > + asm volatile("pacga %0, %1, %2" : "=r" (dest) : "r" (ptr), "r" (modifier)); > + > + return dest; > +} > + > diff --git a/tools/testing/selftests/arm64/pauth/helper.h b/tools/testing/selftests/arm64/pauth/helper.h > index f777f88acf0a..b3cf709e249d 100644 > --- a/tools/testing/selftests/arm64/pauth/helper.h > +++ b/tools/testing/selftests/arm64/pauth/helper.h > @@ -4,7 +4,17 @@ > #ifndef _HELPER_H_ > #define _HELPER_H_ > > +#include <stdlib.h> > + > + > void pac_corruptor(void); > > +/* PAuth sign a value with key ia and modifier value 0 */ > +size_t keyia_sign(size_t val); > +size_t keyib_sign(size_t val); > +size_t keyda_sign(size_t val); > +size_t keydb_sign(size_t val); > +size_t keyg_sign(size_t val); > + > #endif > > diff --git a/tools/testing/selftests/arm64/pauth/pac.c b/tools/testing/selftests/arm64/pauth/pac.c > index ed445050f621..cdbffa8bf61e 100644 > --- a/tools/testing/selftests/arm64/pauth/pac.c > +++ b/tools/testing/selftests/arm64/pauth/pac.c > @@ -12,12 +12,25 @@ > * future version of the arm architecture > */ > > +#define PAC_COLLISION_ATTEMPTS 10 > +/* > + * The kernel sets TBID by default. So bits 55 and above should remain > + * untouched no matter what. > + * The VA space size is 48 bits. Bigger is opt-in. > + */ > +#define PAC_MASK (~0xff80ffffffffffff) > #define ASSERT_PAUTH_ENABLED() \ > do { \ > unsigned long hwcaps = getauxval(AT_HWCAP); \ > /* data key instructions are not in NOP space. This prevents a SIGILL */ \ > ASSERT_NE(0, hwcaps & HWCAP_PACA) TH_LOG("PAUTH not enabled"); \ > } while (0) > +#define ASSERT_GENERIC_PAUTH_ENABLED() \ > +do { \ > + unsigned long hwcaps = getauxval(AT_HWCAP); \ > + /* generic key instructions are not in NOP space. This prevents a SIGILL */ \ > + ASSERT_NE(0, hwcaps & HWCAP_PACG) TH_LOG("Generic PAUTH not enabled"); \ > +} while (0) > > > /* check that a corrupted PAC results in SIGSEGV */ > @@ -28,5 +41,43 @@ TEST_SIGNAL(corrupt_pac, SIGSEGV) > pac_corruptor(); > } > > +/* > + * There are no separate pac* and aut* controls so checking only the pac* > + * instructions is sufficient > + */ > +TEST(pac_instructions_not_nop) > +{ > + size_t keyia = 0; > + size_t keyib = 0; > + size_t keyda = 0; > + size_t keydb = 0; > + > + ASSERT_PAUTH_ENABLED(); > + > + for (int i = 0; i < PAC_COLLISION_ATTEMPTS; i++) { > + keyia |= keyia_sign(i) & PAC_MASK; > + keyib |= keyib_sign(i) & PAC_MASK; > + keyda |= keyda_sign(i) & PAC_MASK; > + keydb |= keydb_sign(i) & PAC_MASK; > + } > + > + ASSERT_NE(0, keyia) TH_LOG("keyia instructions did nothing"); > + ASSERT_NE(0, keyib) TH_LOG("keyib instructions did nothing"); > + ASSERT_NE(0, keyda) TH_LOG("keyda instructions did nothing"); > + ASSERT_NE(0, keydb) TH_LOG("keydb instructions did nothing"); > +} > + > +TEST(pac_instructions_not_nop_generic) > +{ > + size_t keyg = 0; > + > + ASSERT_GENERIC_PAUTH_ENABLED(); > + > + for (int i = 0; i < PAC_COLLISION_ATTEMPTS; i++) > + keyg |= keyg_sign(i) & PAC_MASK; > + > + ASSERT_NE(0, keyg) TH_LOG("keyg instructions did nothing"); > +} > + > TEST_HARNESS_MAIN > >
On 8/28/20 6:46 PM, Boyan Karatotev wrote: > 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. > > Cc: Shuah Khan <shuah@kernel.org> > Cc: Catalin Marinas <catalin.marinas@arm.com> > Cc: Will Deacon <will@kernel.org> > Signed-off-by: Boyan Karatotev <boyan.karatotev@arm.com> The changes look fine so please free to add, Reviewed-by: Amit Daniel Kachhap <amit.kachhap@arm.com> > --- > .../testing/selftests/arm64/pauth/.gitignore | 1 + > tools/testing/selftests/arm64/pauth/Makefile | 7 ++- > tools/testing/selftests/arm64/pauth/helper.c | 41 +++++++++++++++ > tools/testing/selftests/arm64/pauth/helper.h | 10 ++++ > tools/testing/selftests/arm64/pauth/pac.c | 51 +++++++++++++++++++ > 5 files changed, 108 insertions(+), 2 deletions(-) > create mode 100644 tools/testing/selftests/arm64/pauth/helper.c > > diff --git a/tools/testing/selftests/arm64/pauth/.gitignore b/tools/testing/selftests/arm64/pauth/.gitignore > index b557c916720a..155137d92722 100644 > --- a/tools/testing/selftests/arm64/pauth/.gitignore > +++ b/tools/testing/selftests/arm64/pauth/.gitignore > @@ -1 +1,2 @@ > +exec_target > pac > diff --git a/tools/testing/selftests/arm64/pauth/Makefile b/tools/testing/selftests/arm64/pauth/Makefile > index 785c775e5e41..a017d1c8dd58 100644 > --- a/tools/testing/selftests/arm64/pauth/Makefile > +++ b/tools/testing/selftests/arm64/pauth/Makefile > @@ -4,7 +4,7 @@ > CFLAGS += -mbranch-protection=pac-ret > > TEST_GEN_PROGS := pac > -TEST_GEN_FILES := pac_corruptor.o > +TEST_GEN_FILES := pac_corruptor.o helper.o > > include ../../lib.mk > > @@ -13,10 +13,13 @@ include ../../lib.mk > $(OUTPUT)/pac_corruptor.o: pac_corruptor.S > $(CC) -c $^ -o $@ $(CFLAGS) -march=armv8.3-a > > +$(OUTPUT)/helper.o: helper.c > + $(CC) -c $^ -o $@ $(CFLAGS) -march=armv8.3-a > + > # when -mbranch-protection is enabled and the target architecture is ARMv8.3 or > # greater, gcc emits pac* instructions which are not in HINT NOP space, > # preventing the tests from occurring at all. Compile for ARMv8.2 so tests can > # run on earlier targets and print a meaningful error messages > -$(OUTPUT)/pac: pac.c $(OUTPUT)/pac_corruptor.o > +$(OUTPUT)/pac: pac.c $(OUTPUT)/pac_corruptor.o $(OUTPUT)/helper.o > $(CC) $^ -o $@ $(CFLAGS) -march=armv8.2-a > > diff --git a/tools/testing/selftests/arm64/pauth/helper.c b/tools/testing/selftests/arm64/pauth/helper.c > new file mode 100644 > index 000000000000..8619afb16124 > --- /dev/null > +++ b/tools/testing/selftests/arm64/pauth/helper.c > @@ -0,0 +1,41 @@ > +// SPDX-License-Identifier: GPL-2.0 > +// Copyright (C) 2020 ARM Limited > + > +#include "helper.h" > + > + > +size_t keyia_sign(size_t ptr) > +{ > + asm volatile("paciza %0" : "+r" (ptr)); > + return ptr; > +} > + > +size_t keyib_sign(size_t ptr) > +{ > + asm volatile("pacizb %0" : "+r" (ptr)); > + return ptr; > +} > + > +size_t keyda_sign(size_t ptr) > +{ > + asm volatile("pacdza %0" : "+r" (ptr)); > + return ptr; > +} > + > +size_t keydb_sign(size_t ptr) > +{ > + asm volatile("pacdzb %0" : "+r" (ptr)); > + return ptr; > +} > + > +size_t keyg_sign(size_t ptr) > +{ > + /* output is encoded in the upper 32 bits */ > + size_t dest = 0; > + size_t modifier = 0; > + > + asm volatile("pacga %0, %1, %2" : "=r" (dest) : "r" (ptr), "r" (modifier)); > + > + return dest; > +} > + > diff --git a/tools/testing/selftests/arm64/pauth/helper.h b/tools/testing/selftests/arm64/pauth/helper.h > index f777f88acf0a..b3cf709e249d 100644 > --- a/tools/testing/selftests/arm64/pauth/helper.h > +++ b/tools/testing/selftests/arm64/pauth/helper.h > @@ -4,7 +4,17 @@ > #ifndef _HELPER_H_ > #define _HELPER_H_ > > +#include <stdlib.h> > + > + > void pac_corruptor(void); > > +/* PAuth sign a value with key ia and modifier value 0 */ > +size_t keyia_sign(size_t val); > +size_t keyib_sign(size_t val); > +size_t keyda_sign(size_t val); > +size_t keydb_sign(size_t val); > +size_t keyg_sign(size_t val); > + > #endif > > diff --git a/tools/testing/selftests/arm64/pauth/pac.c b/tools/testing/selftests/arm64/pauth/pac.c > index ed445050f621..cdbffa8bf61e 100644 > --- a/tools/testing/selftests/arm64/pauth/pac.c > +++ b/tools/testing/selftests/arm64/pauth/pac.c > @@ -12,12 +12,25 @@ > * future version of the arm architecture > */ > > +#define PAC_COLLISION_ATTEMPTS 10 > +/* > + * The kernel sets TBID by default. So bits 55 and above should remain > + * untouched no matter what. > + * The VA space size is 48 bits. Bigger is opt-in. > + */ > +#define PAC_MASK (~0xff80ffffffffffff) > #define ASSERT_PAUTH_ENABLED() \ > do { \ > unsigned long hwcaps = getauxval(AT_HWCAP); \ > /* data key instructions are not in NOP space. This prevents a SIGILL */ \ > ASSERT_NE(0, hwcaps & HWCAP_PACA) TH_LOG("PAUTH not enabled"); \ > } while (0) > +#define ASSERT_GENERIC_PAUTH_ENABLED() \ > +do { \ > + unsigned long hwcaps = getauxval(AT_HWCAP); \ > + /* generic key instructions are not in NOP space. This prevents a SIGILL */ \ > + ASSERT_NE(0, hwcaps & HWCAP_PACG) TH_LOG("Generic PAUTH not enabled"); \ > +} while (0) > > > /* check that a corrupted PAC results in SIGSEGV */ > @@ -28,5 +41,43 @@ TEST_SIGNAL(corrupt_pac, SIGSEGV) > pac_corruptor(); > } > > +/* > + * There are no separate pac* and aut* controls so checking only the pac* > + * instructions is sufficient > + */ > +TEST(pac_instructions_not_nop) > +{ > + size_t keyia = 0; > + size_t keyib = 0; > + size_t keyda = 0; > + size_t keydb = 0; > + > + ASSERT_PAUTH_ENABLED(); > + > + for (int i = 0; i < PAC_COLLISION_ATTEMPTS; i++) { > + keyia |= keyia_sign(i) & PAC_MASK; > + keyib |= keyib_sign(i) & PAC_MASK; > + keyda |= keyda_sign(i) & PAC_MASK; > + keydb |= keydb_sign(i) & PAC_MASK; > + } > + > + ASSERT_NE(0, keyia) TH_LOG("keyia instructions did nothing"); > + ASSERT_NE(0, keyib) TH_LOG("keyib instructions did nothing"); > + ASSERT_NE(0, keyda) TH_LOG("keyda instructions did nothing"); > + ASSERT_NE(0, keydb) TH_LOG("keydb instructions did nothing"); > +} > + > +TEST(pac_instructions_not_nop_generic) > +{ > + size_t keyg = 0; > + > + ASSERT_GENERIC_PAUTH_ENABLED(); > + > + for (int i = 0; i < PAC_COLLISION_ATTEMPTS; i++) > + keyg |= keyg_sign(i) & PAC_MASK; > + > + ASSERT_NE(0, keyg) TH_LOG("keyg instructions did nothing"); > +} > + > TEST_HARNESS_MAIN > >
diff --git a/tools/testing/selftests/arm64/pauth/.gitignore b/tools/testing/selftests/arm64/pauth/.gitignore index b557c916720a..155137d92722 100644 --- a/tools/testing/selftests/arm64/pauth/.gitignore +++ b/tools/testing/selftests/arm64/pauth/.gitignore @@ -1 +1,2 @@ +exec_target pac diff --git a/tools/testing/selftests/arm64/pauth/Makefile b/tools/testing/selftests/arm64/pauth/Makefile index 785c775e5e41..a017d1c8dd58 100644 --- a/tools/testing/selftests/arm64/pauth/Makefile +++ b/tools/testing/selftests/arm64/pauth/Makefile @@ -4,7 +4,7 @@ CFLAGS += -mbranch-protection=pac-ret TEST_GEN_PROGS := pac -TEST_GEN_FILES := pac_corruptor.o +TEST_GEN_FILES := pac_corruptor.o helper.o include ../../lib.mk @@ -13,10 +13,13 @@ include ../../lib.mk $(OUTPUT)/pac_corruptor.o: pac_corruptor.S $(CC) -c $^ -o $@ $(CFLAGS) -march=armv8.3-a +$(OUTPUT)/helper.o: helper.c + $(CC) -c $^ -o $@ $(CFLAGS) -march=armv8.3-a + # when -mbranch-protection is enabled and the target architecture is ARMv8.3 or # greater, gcc emits pac* instructions which are not in HINT NOP space, # preventing the tests from occurring at all. Compile for ARMv8.2 so tests can # run on earlier targets and print a meaningful error messages -$(OUTPUT)/pac: pac.c $(OUTPUT)/pac_corruptor.o +$(OUTPUT)/pac: pac.c $(OUTPUT)/pac_corruptor.o $(OUTPUT)/helper.o $(CC) $^ -o $@ $(CFLAGS) -march=armv8.2-a diff --git a/tools/testing/selftests/arm64/pauth/helper.c b/tools/testing/selftests/arm64/pauth/helper.c new file mode 100644 index 000000000000..8619afb16124 --- /dev/null +++ b/tools/testing/selftests/arm64/pauth/helper.c @@ -0,0 +1,41 @@ +// SPDX-License-Identifier: GPL-2.0 +// Copyright (C) 2020 ARM Limited + +#include "helper.h" + + +size_t keyia_sign(size_t ptr) +{ + asm volatile("paciza %0" : "+r" (ptr)); + return ptr; +} + +size_t keyib_sign(size_t ptr) +{ + asm volatile("pacizb %0" : "+r" (ptr)); + return ptr; +} + +size_t keyda_sign(size_t ptr) +{ + asm volatile("pacdza %0" : "+r" (ptr)); + return ptr; +} + +size_t keydb_sign(size_t ptr) +{ + asm volatile("pacdzb %0" : "+r" (ptr)); + return ptr; +} + +size_t keyg_sign(size_t ptr) +{ + /* output is encoded in the upper 32 bits */ + size_t dest = 0; + size_t modifier = 0; + + asm volatile("pacga %0, %1, %2" : "=r" (dest) : "r" (ptr), "r" (modifier)); + + return dest; +} + diff --git a/tools/testing/selftests/arm64/pauth/helper.h b/tools/testing/selftests/arm64/pauth/helper.h index f777f88acf0a..b3cf709e249d 100644 --- a/tools/testing/selftests/arm64/pauth/helper.h +++ b/tools/testing/selftests/arm64/pauth/helper.h @@ -4,7 +4,17 @@ #ifndef _HELPER_H_ #define _HELPER_H_ +#include <stdlib.h> + + void pac_corruptor(void); +/* PAuth sign a value with key ia and modifier value 0 */ +size_t keyia_sign(size_t val); +size_t keyib_sign(size_t val); +size_t keyda_sign(size_t val); +size_t keydb_sign(size_t val); +size_t keyg_sign(size_t val); + #endif diff --git a/tools/testing/selftests/arm64/pauth/pac.c b/tools/testing/selftests/arm64/pauth/pac.c index ed445050f621..cdbffa8bf61e 100644 --- a/tools/testing/selftests/arm64/pauth/pac.c +++ b/tools/testing/selftests/arm64/pauth/pac.c @@ -12,12 +12,25 @@ * future version of the arm architecture */ +#define PAC_COLLISION_ATTEMPTS 10 +/* + * The kernel sets TBID by default. So bits 55 and above should remain + * untouched no matter what. + * The VA space size is 48 bits. Bigger is opt-in. + */ +#define PAC_MASK (~0xff80ffffffffffff) #define ASSERT_PAUTH_ENABLED() \ do { \ unsigned long hwcaps = getauxval(AT_HWCAP); \ /* data key instructions are not in NOP space. This prevents a SIGILL */ \ ASSERT_NE(0, hwcaps & HWCAP_PACA) TH_LOG("PAUTH not enabled"); \ } while (0) +#define ASSERT_GENERIC_PAUTH_ENABLED() \ +do { \ + unsigned long hwcaps = getauxval(AT_HWCAP); \ + /* generic key instructions are not in NOP space. This prevents a SIGILL */ \ + ASSERT_NE(0, hwcaps & HWCAP_PACG) TH_LOG("Generic PAUTH not enabled"); \ +} while (0) /* check that a corrupted PAC results in SIGSEGV */ @@ -28,5 +41,43 @@ TEST_SIGNAL(corrupt_pac, SIGSEGV) pac_corruptor(); } +/* + * There are no separate pac* and aut* controls so checking only the pac* + * instructions is sufficient + */ +TEST(pac_instructions_not_nop) +{ + size_t keyia = 0; + size_t keyib = 0; + size_t keyda = 0; + size_t keydb = 0; + + ASSERT_PAUTH_ENABLED(); + + for (int i = 0; i < PAC_COLLISION_ATTEMPTS; i++) { + keyia |= keyia_sign(i) & PAC_MASK; + keyib |= keyib_sign(i) & PAC_MASK; + keyda |= keyda_sign(i) & PAC_MASK; + keydb |= keydb_sign(i) & PAC_MASK; + } + + ASSERT_NE(0, keyia) TH_LOG("keyia instructions did nothing"); + ASSERT_NE(0, keyib) TH_LOG("keyib instructions did nothing"); + ASSERT_NE(0, keyda) TH_LOG("keyda instructions did nothing"); + ASSERT_NE(0, keydb) TH_LOG("keydb instructions did nothing"); +} + +TEST(pac_instructions_not_nop_generic) +{ + size_t keyg = 0; + + ASSERT_GENERIC_PAUTH_ENABLED(); + + for (int i = 0; i < PAC_COLLISION_ATTEMPTS; i++) + keyg |= keyg_sign(i) & PAC_MASK; + + ASSERT_NE(0, keyg) TH_LOG("keyg instructions did nothing"); +} + TEST_HARNESS_MAIN
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. Cc: Shuah Khan <shuah@kernel.org> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: Will Deacon <will@kernel.org> Signed-off-by: Boyan Karatotev <boyan.karatotev@arm.com> --- .../testing/selftests/arm64/pauth/.gitignore | 1 + tools/testing/selftests/arm64/pauth/Makefile | 7 ++- tools/testing/selftests/arm64/pauth/helper.c | 41 +++++++++++++++ tools/testing/selftests/arm64/pauth/helper.h | 10 ++++ tools/testing/selftests/arm64/pauth/pac.c | 51 +++++++++++++++++++ 5 files changed, 108 insertions(+), 2 deletions(-) create mode 100644 tools/testing/selftests/arm64/pauth/helper.c