Merge tag 'random_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/random
Pull random updates from Ted Ts'o:
"A few /dev/random improvements for the v3.8 merge window."
* tag 'random_for_linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tytso/random:
random: Mix cputime from each thread that exits to the pool
random: prime last_data value per fips requirements
random: fix debug format strings
random: make it possible to enable debugging without rebuild
diff --git a/drivers/char/random.c b/drivers/char/random.c
index b86eae9..85e81ec 100644
--- a/drivers/char/random.c
+++ b/drivers/char/random.c
@@ -399,7 +399,6 @@
static DECLARE_WAIT_QUEUE_HEAD(random_write_wait);
static struct fasync_struct *fasync;
-#if 0
static bool debug;
module_param(debug, bool, 0644);
#define DEBUG_ENT(fmt, arg...) do { \
@@ -410,9 +409,6 @@
blocking_pool.entropy_count,\
nonblocking_pool.entropy_count,\
## arg); } while (0)
-#else
-#define DEBUG_ENT(fmt, arg...) do {} while (0)
-#endif
/**********************************************************************
*
@@ -437,6 +433,7 @@
int entropy_count;
int entropy_total;
unsigned int initialized:1;
+ bool last_data_init;
__u8 last_data[EXTRACT_SIZE];
};
@@ -829,7 +826,7 @@
bytes = min_t(int, bytes, sizeof(tmp));
DEBUG_ENT("going to reseed %s with %d bits "
- "(%d of %d requested)\n",
+ "(%zu of %d requested)\n",
r->name, bytes * 8, nbytes * 8, r->entropy_count);
bytes = extract_entropy(r->pull, tmp, bytes,
@@ -860,7 +857,7 @@
spin_lock_irqsave(&r->lock, flags);
BUG_ON(r->entropy_count > r->poolinfo->POOLBITS);
- DEBUG_ENT("trying to extract %d bits from %s\n",
+ DEBUG_ENT("trying to extract %zu bits from %s\n",
nbytes * 8, r->name);
/* Can we pull enough? */
@@ -882,7 +879,7 @@
}
}
- DEBUG_ENT("debiting %d entropy credits from %s%s\n",
+ DEBUG_ENT("debiting %zu entropy credits from %s%s\n",
nbytes * 8, r->name, r->limit ? "" : " (unlimited)");
spin_unlock_irqrestore(&r->lock, flags);
@@ -957,6 +954,10 @@
ssize_t ret = 0, i;
__u8 tmp[EXTRACT_SIZE];
+ /* if last_data isn't primed, we need EXTRACT_SIZE extra bytes */
+ if (fips_enabled && !r->last_data_init)
+ nbytes += EXTRACT_SIZE;
+
trace_extract_entropy(r->name, nbytes, r->entropy_count, _RET_IP_);
xfer_secondary_pool(r, nbytes);
nbytes = account(r, nbytes, min, reserved);
@@ -967,6 +968,17 @@
if (fips_enabled) {
unsigned long flags;
+
+ /* prime last_data value if need be, per fips 140-2 */
+ if (!r->last_data_init) {
+ spin_lock_irqsave(&r->lock, flags);
+ memcpy(r->last_data, tmp, EXTRACT_SIZE);
+ r->last_data_init = true;
+ nbytes -= EXTRACT_SIZE;
+ spin_unlock_irqrestore(&r->lock, flags);
+ extract_buf(r, tmp);
+ }
+
spin_lock_irqsave(&r->lock, flags);
if (!memcmp(tmp, r->last_data, EXTRACT_SIZE))
panic("Hardware RNG duplicated output!\n");
@@ -1086,6 +1098,7 @@
r->entropy_count = 0;
r->entropy_total = 0;
+ r->last_data_init = false;
mix_pool_bytes(r, &now, sizeof(now), NULL);
for (i = r->poolinfo->POOLBYTES; i > 0; i -= sizeof(rv)) {
if (!arch_get_random_long(&rv))
@@ -1142,11 +1155,16 @@
if (n > SEC_XFER_SIZE)
n = SEC_XFER_SIZE;
- DEBUG_ENT("reading %d bits\n", n*8);
+ DEBUG_ENT("reading %zu bits\n", n*8);
n = extract_entropy_user(&blocking_pool, buf, n);
- DEBUG_ENT("read got %d bits (%d still needed)\n",
+ if (n < 0) {
+ retval = n;
+ break;
+ }
+
+ DEBUG_ENT("read got %zd bits (%zd still needed)\n",
n*8, (nbytes-n)*8);
if (n == 0) {
@@ -1171,10 +1189,6 @@
continue;
}
- if (n < 0) {
- retval = n;
- break;
- }
count += n;
buf += n;
nbytes -= n;
diff --git a/kernel/posix-cpu-timers.c b/kernel/posix-cpu-timers.c
index d738402..a278cad 100644
--- a/kernel/posix-cpu-timers.c
+++ b/kernel/posix-cpu-timers.c
@@ -9,6 +9,7 @@
#include <asm/uaccess.h>
#include <linux/kernel_stat.h>
#include <trace/events/timer.h>
+#include <linux/random.h>
/*
* Called after updating RLIMIT_CPU to run cpu timer and update
@@ -470,6 +471,8 @@
*/
void posix_cpu_timers_exit(struct task_struct *tsk)
{
+ add_device_randomness((const void*) &tsk->se.sum_exec_runtime,
+ sizeof(unsigned long long));
cleanup_timers(tsk->cpu_timers,
tsk->utime, tsk->stime, tsk->se.sum_exec_runtime);