diff mbox series

[v2,12/14] linux-user/aarch64: Use qemu_getrandom for arm_init_pauth_key

Message ID 20190314045526.13342-13-richard.henderson@linaro.org
State New
Headers show
Series Add qemu_getrandom and ARMv8.5-RNG | expand

Commit Message

Richard Henderson March 14, 2019, 4:55 a.m. UTC
Use a better interface for random numbers than rand * 3.

Cc: Laurent Vivier <laurent@vivier.eu>
Cc: Peter Maydell <peter.maydell@linaro.org>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>

---
 linux-user/aarch64/cpu_loop.c | 16 ++--------------
 1 file changed, 2 insertions(+), 14 deletions(-)

-- 
2.17.1

Comments

Philippe Mathieu-Daudé March 14, 2019, 9:55 p.m. UTC | #1
On 3/14/19 5:55 AM, Richard Henderson wrote:
> Use a better interface for random numbers than rand * 3.

> 

> Cc: Laurent Vivier <laurent@vivier.eu>

> Cc: Peter Maydell <peter.maydell@linaro.org>

> Signed-off-by: Richard Henderson <richard.henderson@linaro.org>

> ---

>  linux-user/aarch64/cpu_loop.c | 16 ++--------------

>  1 file changed, 2 insertions(+), 14 deletions(-)

> 

> diff --git a/linux-user/aarch64/cpu_loop.c b/linux-user/aarch64/cpu_loop.c

> index d75fd9d3e2..ad30cab52d 100644

> --- a/linux-user/aarch64/cpu_loop.c

> +++ b/linux-user/aarch64/cpu_loop.c

> @@ -20,6 +20,7 @@

>  #include "qemu/osdep.h"

>  #include "qemu.h"

>  #include "cpu_loop-common.h"

> +#include "qemu/random.h"

>  

>  #define get_user_code_u32(x, gaddr, env)                \

>      ({ abi_long __r = get_user_u32((x), (gaddr));       \

> @@ -147,22 +148,9 @@ void cpu_loop(CPUARMState *env)

>      }

>  }

>  

> -static uint64_t arm_rand64(void)

> -{

> -    int shift = 64 - clz64(RAND_MAX);

> -    int i, n = 64 / shift + (64 % shift != 0);

> -    uint64_t ret = 0;

> -

> -    for (i = 0; i < n; i++) {

> -        ret = (ret << shift) | rand();

> -    }

> -    return ret;

> -}

> -

>  void arm_init_pauth_key(ARMPACKey *key)

>  {

> -    key->lo = arm_rand64();

> -    key->hi = arm_rand64();

> +    qemu_getrandom(key, sizeof(*key), false);


PAC keys are define by a AA64 spec so are unlikely to have their
structure modified, thus:

Reviewed-by: Philippe Mathieu-Daudé <philmd@redhat.com>


>  }

>  

>  void target_cpu_copy_regs(CPUArchState *env, struct target_pt_regs *regs)

>
diff mbox series

Patch

diff --git a/linux-user/aarch64/cpu_loop.c b/linux-user/aarch64/cpu_loop.c
index d75fd9d3e2..ad30cab52d 100644
--- a/linux-user/aarch64/cpu_loop.c
+++ b/linux-user/aarch64/cpu_loop.c
@@ -20,6 +20,7 @@ 
 #include "qemu/osdep.h"
 #include "qemu.h"
 #include "cpu_loop-common.h"
+#include "qemu/random.h"
 
 #define get_user_code_u32(x, gaddr, env)                \
     ({ abi_long __r = get_user_u32((x), (gaddr));       \
@@ -147,22 +148,9 @@  void cpu_loop(CPUARMState *env)
     }
 }
 
-static uint64_t arm_rand64(void)
-{
-    int shift = 64 - clz64(RAND_MAX);
-    int i, n = 64 / shift + (64 % shift != 0);
-    uint64_t ret = 0;
-
-    for (i = 0; i < n; i++) {
-        ret = (ret << shift) | rand();
-    }
-    return ret;
-}
-
 void arm_init_pauth_key(ARMPACKey *key)
 {
-    key->lo = arm_rand64();
-    key->hi = arm_rand64();
+    qemu_getrandom(key, sizeof(*key), false);
 }
 
 void target_cpu_copy_regs(CPUArchState *env, struct target_pt_regs *regs)