[v8,14/25] linux-user: Use qemu_guest_getrandom_nofail for AT_RANDOM

Commit Message

Richard Henderson May 17, 2019, 2:39 a.m. UTC

Use a better interface for random numbers than rand * 16.

Reviewed-by: Laurent Vivier <[e-mail]>
Reviewed-by: Philippe Mathieu-Daudé <[e-mail]>
Signed-off-by: Richard Henderson <[e-mail]>
---
 linux-user/elfload.c | 8 +++-----
 1 file changed, 3 insertions(+), 5 deletions(-)

Patch

diff --git a/linux-user/elfload.c b/linux-user/elfload.c
index ef42e02d82..1e06b908b7 100644
--- a/linux-user/elfload.c
+++ b/linux-user/elfload.c
@@ -7,6 +7,7 @@ 
 #include "qemu.h"
 #include "disas/disas.h"
 #include "qemu/path.h"
+#include "qemu/guest-random.h"
 
 #ifdef _ARCH_PPC64
 #undef ARCH_DLINFO
@@ -1883,12 +1884,9 @@  static abi_ulong create_elf_tables(abi_ulong p, int argc, int envc,
     }
 
     /*
-     * Generate 16 random bytes for userspace PRNG seeding (not
-     * cryptically secure but it's not the aim of QEMU).
+     * Generate 16 random bytes for userspace PRNG seeding.
      */
-    for (i = 0; i < 16; i++) {
-        k_rand_bytes[i] = rand();
-    }
+    qemu_guest_getrandom_nofail(k_rand_bytes, sizeof(k_rand_bytes));
     if (STACK_GROWS_DOWN) {
         sp -= 16;
         u_rand_bytes = sp;