linux/include
Yuchung Cheng 27cde44a25 tcp: do not cancel delay-AcK on DCTCP special ACK
Currently when a DCTCP receiver delays an ACK and receive a
data packet with a different CE mark from the previous one's, it
sends two immediate ACKs acking previous and latest sequences
respectly (for ECN accounting).

Previously sending the first ACK may mark off the delayed ACK timer
(tcp_event_ack_sent). This may subsequently prevent sending the
second ACK to acknowledge the latest sequence (tcp_ack_snd_check).
The culprit is that tcp_send_ack() assumes it always acknowleges
the latest sequence, which is not true for the first special ACK.

The fix is to not make the assumption in tcp_send_ack and check the
actual ack sequence before cancelling the delayed ACK. Further it's
safer to pass the ack sequence number as a local variable into
tcp_send_ack routine, instead of intercepting tp->rcv_nxt to avoid
future bugs like this.

Reported-by: Neal Cardwell <ncardwell@google.com>
Signed-off-by: Yuchung Cheng <ycheng@google.com>
Acked-by: Neal Cardwell <ncardwell@google.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2018-07-20 14:32:23 -07:00
..
acpi ACPI / processor: Finish making acpi_processor_ppc_has_changed() void 2018-06-20 10:50:40 +02:00
asm-generic mm: allow arch to supply p??_free_tlb functions 2018-07-14 11:11:09 -07:00
clocksource
crypto Revert changes to convert to ->poll_mask() and aio IOCB_CMD_POLL 2018-06-28 10:40:47 -07:00
drm drm for v4.18-rc1 2018-06-06 08:16:33 -07:00
dt-bindings dt-bindings: clock: imx6ul: Do not change the clock definition order 2018-06-29 11:40:20 -07:00
keys docs: Fix some broken references 2018-06-15 18:10:01 -03:00
kvm KVM: arm/arm64: Bump VGIC_V3_MAX_CPUS to 512 2018-05-25 12:29:27 +01:00
linux Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2018-07-18 19:32:54 -07:00
math-emu
media media: v4l2-core: push taking ioctl mutex down to ioctl handler 2018-05-28 16:31:44 -04:00
memory
misc ocxl: Expose the thread_id needed for wait on POWER9 2018-06-03 20:40:32 +10:00
net tcp: do not cancel delay-AcK on DCTCP special ACK 2018-07-20 14:32:23 -07:00
pcmcia
ras
rdma 4.18-rc 2018-06-21 07:22:30 +09:00
scsi SCSI misc on 20180610 2018-06-10 13:01:12 -07:00
soc ARM: SoC: late updates 2018-06-11 18:19:45 -07:00
sound sound updates for 4.18 2018-06-06 09:08:38 -07:00
target
trace NFS client updates for Linux 4.18 2018-06-12 10:09:03 -07:00
uapi Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2018-07-18 19:32:54 -07:00
video fbdev changes for v4.18: 2018-06-17 05:00:24 +09:00
xen xen: fixes for 4.18-rc2 2018-06-23 20:44:11 +08:00