From: Theodore Ts'o <[email protected]>

                   -------------------
    This is a commit scheduled for the next v2.6.34 longterm release.
    http://git.kernel.org/?p=linux/kernel/git/paulg/longterm-queue-2.6.34.git
    If you see a problem with using this for longterm, please comment.
                   -------------------

commit 3e88bdff1c65145f7ba297ccec69c774afe4c785 upstream.

If there is an architecture-specific random number generator (such as
RDRAND for Intel architectures), use it to initialize /dev/random's
entropy stores.  Even in the worst case, if RDRAND is something like
AES(NSA_KEY, counter++), it won't hurt, and it will definitely help
against any other adversaries.

Signed-off-by: "Theodore Ts'o" <[email protected]>
Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: H. Peter Anvin <[email protected]>
Signed-off-by: Paul Gortmaker <[email protected]>
---
 drivers/char/random.c | 6 ++++++
 1 file changed, 6 insertions(+)

diff --git a/drivers/char/random.c b/drivers/char/random.c
index ed86cae..4874f55 100644
--- a/drivers/char/random.c
+++ b/drivers/char/random.c
@@ -958,6 +958,7 @@ EXPORT_SYMBOL(get_random_bytes);
  */
 static void init_std_data(struct entropy_store *r)
 {
+       int i;
        ktime_t now;
        unsigned long flags;
 
@@ -967,6 +968,11 @@ static void init_std_data(struct entropy_store *r)
 
        now = ktime_get_real();
        mix_pool_bytes(r, &now, sizeof(now));
+       for (i = r->poolinfo->poolwords; i; i--) {
+               if (!arch_get_random_long(&flags))
+                       break;
+               mix_pool_bytes(r, &flags, sizeof(flags));
+       }
        mix_pool_bytes(r, utsname(), sizeof(*(utsname())));
 }
 
-- 
1.7.12.rc2

--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to [email protected]
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

Reply via email to