sctp: Error in calculation of RTTvar
authorSchoch Christian <e0326715@student.tuwien.ac.at>
Wed, 28 Nov 2012 05:18:29 +0000 (05:18 +0000)
committerDavid S. Miller <davem@davemloft.net>
Wed, 28 Nov 2012 16:13:40 +0000 (11:13 -0500)
commit92d64c261e77cb2a6117887617e2a629fea6b67c
tree0021d03d1c34acb7ab099ad66bbec6f28d658613
parent6e51fe7572590d8d86e93b547fab6693d305fd0d
sctp: Error in calculation of RTTvar

The calculation of RTTVAR involves the subtraction of two unsigned
numbers which
may causes rollover and results in very high values of RTTVAR when RTT > SRTT.
With this patch it is possible to set RTOmin = 1 to get the minimum of RTO at
4 times the clock granularity.

Change Notes:

v2)
        *Replaced abs() by abs64() and long by __s64, changed patch
description.

Signed-off-by: Christian Schoch <e0326715@student.tuwien.ac.at>
CC: Vlad Yasevich <vyasevich@gmail.com>
CC: Sridhar Samudrala <sri@us.ibm.com>
CC: Neil Horman <nhorman@tuxdriver.com>
CC: linux-sctp@vger.kernel.org
Acked-by: Vlad Yasevich <vyasevich@gmail.com>
Acked-by: Neil Horman <nhorman@tuxdriver.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
net/sctp/transport.c