This is a note to let you know that I've just added the patch titled
tcp_nv: fix division by zero in tcpnv_acked()
to the 4.9-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
tcp_nv-fix-division-by-zero-in-tcpnv_acked.patch
and it can be found in the queue-4.9 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
>From foo@baz Tue Nov 21 13:08:13 CET 2017
From: Konstantin Khlebnikov <khlebnikov@xxxxxxxxxxxxxx>
Date: Wed, 1 Nov 2017 16:32:15 +0300
Subject: tcp_nv: fix division by zero in tcpnv_acked()
From: Konstantin Khlebnikov <khlebnikov@xxxxxxxxxxxxxx>
[ Upstream commit 4eebff27ca4182bbf5f039dd60d79e2d7c0a707e ]
Average RTT could become zero. This happened in real life at least twice.
This patch treats zero as 1us.
Signed-off-by: Konstantin Khlebnikov <khlebnikov@xxxxxxxxxxxxxx>
Acked-by: Lawrence Brakmo <Brakmo@xxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
net/ipv4/tcp_nv.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
--- a/net/ipv4/tcp_nv.c
+++ b/net/ipv4/tcp_nv.c
@@ -263,7 +263,7 @@ static void tcpnv_acked(struct sock *sk,
/* rate in 100's bits per second */
rate64 = ((u64)sample->in_flight) * 8000000;
- rate = (u32)div64_u64(rate64, (u64)(avg_rtt * 100));
+ rate = (u32)div64_u64(rate64, (u64)(avg_rtt ?: 1) * 100);
/* Remember the maximum rate seen during this RTT
* Note: It may be more than one RTT. This function should be
Patches currently in stable-queue which might be from khlebnikov@xxxxxxxxxxxxxx are
queue-4.9/tcp_nv-fix-division-by-zero-in-tcpnv_acked.patch