Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit 6dd10a62 authored by Eric Dumazet's avatar Eric Dumazet Committed by David S. Miller
Browse files

[NET] random : secure_tcp_sequence_number should not assume CONFIG_KTIME_SCALAR 



All 32 bits machines but i386 dont have CONFIG_KTIME_SCALAR. On these
machines, ktime.tv64 is more than 4 times the (correct) result given
by ktime_to_ns()

Again on these machines, using ktime_get_real().tv64 >> 6 give a
32bits rollover every 64 seconds, which is not wanted (less than the
120 s MSL)

Using ktime_to_ns() is the portable way to get nsecs from a ktime, and
have correct code.

Signed-off-by: default avatarEric Dumazet <dada1@cosmosbay.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent cb4da1a3

drivers/char/random.c

+3 −3
Original line number Diff line number Diff line
@@ -1494,7 +1494,7 @@ __u32 secure_tcpv6_sequence_number(__be32 *saddr, __be32 *daddr, 
	seq = twothirdsMD4Transform((const __u32 *)daddr, hash) & HASH_MASK;

	seq += keyptr->count;



	seq += ktime_get_real().tv64;

	seq += ktime_to_ns(ktime_get_real());



	return seq;

}
@@ -1556,7 +1556,7 @@ __u32 secure_tcp_sequence_number(__be32 saddr, __be32 daddr, 
	 *	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 >> 6;

	seq += ktime_to_ns(ktime_get_real()) >> 6;

#if 0

	printk("init_seq(%lx, %lx, %d, %d) = %d\n",

	       saddr, daddr, sport, dport, seq);
@@ -1616,7 +1616,7 @@ u64 secure_dccp_sequence_number(__be32 saddr, __be32 daddr, 
	seq = half_md4_transform(hash, keyptr->secret);

	seq |= ((u64)keyptr->count) << (32 - HASH_BITS);



	seq += ktime_get_real().tv64;

	seq += ktime_to_ns(ktime_get_real());

	seq &= (1ull << 48) - 1;

#if 0

	printk("dccp init_seq(%lx, %lx, %d, %d) = %d\n",