GitHub-Mirror/Star64_linux
2
0
Fork 0
mirror of https://github.com/Fishwaldo/Star64_linux.git synced 2025-06-22 06:32:08 +00:00
Code Issues Projects Releases Packages Wiki Activity Actions

tcp: avoid possible arithmetic overflows

Browse source 
icsk_rto is a 32bit field, and icsk_backoff can reach 15 by default,
or more if some sysctl (eg tcp_retries2) are changed.

Better use 64bit to perform icsk_rto << icsk_backoff operations

As Joe Perches suggested, add a helper for this.

Yuchung spotted the tcp_v4_err() case.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Eric Dumazet 2014-09-22 13:19:44 -07:00 • committed by David S. Miller
parent 35f7aa5309
commit fcdd1cf4dd
5 changed files with 23 additions and 14 deletions
Download patch file Download diff file Expand all files Collapse all files

5
net/ipv4/tcp_input.c
View file

@ -3208,9 +3208,10 @@ static void tcp_ack_probe(struct sock *sk)
* This function is not for random using!
*/
} else {
unsigned long when = inet_csk_rto_backoff(icsk, TCP_RTO_MAX);
inet_csk_reset_xmit_timer(sk, ICSK_TIME_PROBE0,
min(icsk->icsk_rto << icsk->icsk_backoff, TCP_RTO_MAX),
TCP_RTO_MAX);
when, TCP_RTO_MAX);
}
}