[PATCH v2 07/10] x86: Mark archrandom.h functions __must_check

Mark Brown
2020-01-10T14:54:43Z

We must not use the pointer output without validating the
success of the random read.

Reviewed-by: Ard Biesheuvel <ardb@kernel.org>
Signed-off-by: Richard Henderson <rth@twiddle.net>
Signed-off-by: Mark Brown <broonie@kernel.org>
---
arch/x86/include/asm/archrandom.h | 16 ++++++++--------
1 file changed, 8 insertions(+), 8 deletions(-)

diff --git a/arch/x86/include/asm/archrandom.h b/arch/x86/include/asm/archrandom.h
index feb59461046c..7a4bb1bd4bdb 100644
--- a/arch/x86/include/asm/archrandom.h
+++ b/arch/x86/include/asm/archrandom.h
@@ -27,7 +27,7 @@

/* Unconditional execution of RDRAND and RDSEED */

-static inline bool rdrand_long(unsigned long *v)
+static inline bool __must_check rdrand_long(unsigned long *v)
{
bool ok;
unsigned int retry = RDRAND_RETRY_LOOPS;
@@ -41,7 +41,7 @@ static inline bool rdrand_long(unsigned long *v)
return false;
}

-static inline bool rdrand_int(unsigned int *v)
+static inline bool __must_check rdrand_int(unsigned int *v)
{
bool ok;
unsigned int retry = RDRAND_RETRY_LOOPS;
@@ -55,7 +55,7 @@ static inline bool rdrand_int(unsigned int *v)
return false;
}

-static inline bool rdseed_long(unsigned long *v)
+static inline bool __must_check rdseed_long(unsigned long *v)
{
bool ok;
asm volatile(RDSEED_LONG
@@ -64,7 +64,7 @@ static inline bool rdseed_long(unsigned long *v)
return ok;
}

-static inline bool rdseed_int(unsigned int *v)
+static inline bool __must_check rdseed_int(unsigned int *v)
{
bool ok;
asm volatile(RDSEED_INT
@@ -80,22 +80,22 @@ static inline bool rdseed_int(unsigned int *v)
*/
#ifdef CONFIG_ARCH_RANDOM

-static inline bool arch_get_random_long(unsigned long *v)
+static inline bool __must_check arch_get_random_long(unsigned long *v)
{
return static_cpu_has(X86_FEATURE_RDRAND) ? rdrand_long(v) : false;
}

-static inline bool arch_get_random_int(unsigned int *v)
+static inline bool __must_check arch_get_random_int(unsigned int *v)
{
return static_cpu_has(X86_FEATURE_RDRAND) ? rdrand_int(v) : false;
}

-static inline bool arch_get_random_seed_long(unsigned long *v)
+static inline bool __must_check arch_get_random_seed_long(unsigned long *v)
{
return static_cpu_has(X86_FEATURE_RDSEED) ? rdseed_long(v) : false;
}

-static inline bool arch_get_random_seed_int(unsigned int *v)
+static inline bool __must_check arch_get_random_seed_int(unsigned int *v)
{
return static_cpu_has(X86_FEATURE_RDSEED) ? rdseed_int(v) : false;
}
--
2.20.1