rcu_random uses a counter rrs_count to occasionally mix data from
get_random_bytes into the state of its pseudorandom generator. However, the
rrs_counter gets declared as an unsigned long, and rcu_random checks for
--rrs_count < 0, so this code will never mix any real random data into the
state, and will thus always return the same sequence of random numbers.
Also, change the return value of rcu_random from long to unsigned long, to
avoid potential issues caused by the use of the % operator, which can return
negative values for negative left operands.
Signed-off-by: Josh Triplett <[email protected]>
---
kernel/rcutorture.c | 4 ++--
1 files changed, 2 insertions(+), 2 deletions(-)
diff --git a/kernel/rcutorture.c b/kernel/rcutorture.c
index 8b09c95..ef6a124 100644
--- a/kernel/rcutorture.c
+++ b/kernel/rcutorture.c
@@ -146,7 +146,7 @@ rcu_torture_free(struct rcu_torture *p)
struct rcu_random_state {
unsigned long rrs_state;
- unsigned long rrs_count;
+ long rrs_count;
};
#define RCU_RANDOM_MULT 39916801 /* prime */
@@ -159,7 +159,7 @@ #define DEFINE_RCU_RANDOM(name) struct r
* Crude but fast random-number generator. Uses a linear congruential
* generator, with occasional help from get_random_bytes().
*/
-static long
+static unsigned long
rcu_random(struct rcu_random_state *rrsp)
{
long refresh;
--
1.4.1.1
-
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/
[Index of Archives]
[Kernel Newbies]
[Netfilter]
[Bugtraq]
[Photo]
[Stuff]
[Gimp]
[Yosemite News]
[MIPS Linux]
[ARM Linux]
[Linux Security]
[Linux RAID]
[Video 4 Linux]
[Linux for the blind]
[Linux Resources]
