Merge branch 'xen-upstream' of git://git.kernel.org/pub/scm/linux/kernel/git/jeremy/xen

[mv-sheeva.git] / drivers / char / random.c

diff --git a/drivers/char/random.c b/drivers/char/random.c
index 0474cac4a84ed882e4bb92d825beb1afcb6db69f..af274e5a25ee5ec57533eff3a4e869feac831924 100644 (file)
--- a/drivers/char/random.c
+++ b/drivers/char/random.c
@@ -693,9 +693,14 @@ static void xfer_secondary_pool(struct entropy_store *r, size_t nbytes)
 
        if (r->pull && r->entropy_count < nbytes * 8 &&
            r->entropy_count < r->poolinfo->POOLBITS) {
-               int bytes = max_t(int, random_read_wakeup_thresh / 8,
-                               min_t(int, nbytes, sizeof(tmp)));
+               /* If we're limited, always leave two wakeup worth's BITS */
                int rsvd = r->limit ? 0 : random_read_wakeup_thresh/4;
+               int bytes = nbytes;
+
+               /* pull at least as many as BYTES as wakeup BITS */
+               bytes = max_t(int, bytes, random_read_wakeup_thresh / 8);
+               /* but never more than the buffer size */
+               bytes = min_t(int, bytes, sizeof(tmp));
 
                DEBUG_ENT("going to reseed %s with %d bits "
                          "(%d of %d requested)\n",
@@ -794,7 +799,7 @@ static void extract_buf(struct entropy_store *r, __u8 *out)
 
        buf[0] ^= buf[3];
        buf[1] ^= buf[4];
-       buf[0] ^= rol32(buf[3], 16);
+       buf[2] ^= rol32(buf[2], 16);
        memcpy(out, buf, EXTRACT_SIZE);
        memset(buf, 0, sizeof(buf));
 }
@@ -1545,11 +1550,13 @@ __u32 secure_tcp_sequence_number(__be32 saddr, __be32 daddr,
         *      As close as possible to RFC 793, which
         *      suggests using a 250 kHz clock.
         *      Further reading shows this assumes 2 Mb/s networks.
-        *      For 10 Gb/s Ethernet, a 1 GHz clock is appropriate.
-        *      That's funny, Linux has one built in!  Use it!
-        *      (Networks are faster now - should this be increased?)
+        *      For 10 Mb/s Ethernet, a 1 MHz clock is appropriate.
+        *      For 10 Gb/s Ethernet, a 1 GHz clock should be ok, but
+        *      we also need to limit the resolution so that the u32 seq
+        *      overlaps less than one time per MSL (2 minutes).
+        *      Choosing a clock of 64 ns period is OK. (period of 274 s)
         */
-       seq += ktime_get_real().tv64;
+       seq += ktime_get_real().tv64 >> 6;
 #if 0
        printk("init_seq(%lx, %lx, %d, %d) = %d\n",
               saddr, daddr, sport, dport, seq);