We must not use the pointer output without validating the success of the random read. Reviewed-by: Ard Biesheuvel <ardb@xxxxxxxxxx> Signed-off-by: Richard Henderson <rth@xxxxxxxxxxx> --- 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; } -- 2.17.1