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-rw-r--r--drivers/char/random.c10
1 files changed, 6 insertions, 4 deletions
diff --git a/drivers/char/random.c b/drivers/char/random.c
index 397c714cf2ba..af274e5a25ee 100644
--- a/drivers/char/random.c
+++ b/drivers/char/random.c
@@ -1550,11 +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);
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