Eric Dumazet 99779c24bf tcp: fix SO_RCVLOWAT hangs with fat skbs ... [ Upstream commit 24adbc1676 ] We autotune rcvbuf whenever SO_RCVLOWAT is set to account for 100% overhead in tcp_set_rcvlowat() This works well when skb->len/skb->truesize ratio is bigger than 0.5 But if we receive packets with small MSS, we can end up in a situation where not enough bytes are available in the receive queue to satisfy RCVLOWAT setting. As our sk_rcvbuf limit is hit, we send zero windows in ACK packets, preventing remote peer from sending more data. Even autotuning does not help, because it only triggers at the time user process drains the queue. If no EPOLLIN is generated, this can not happen. Note poll() has a similar issue, after commit c7004482e8 ("tcp: Respect SO_RCVLOWAT in tcp_poll().") Fixes: 03f45c883c ("tcp: avoid extra wakeups for SO_RCVLOWAT users") Signed-off-by: Eric Dumazet <edumazet@google.com> Acked-by: Soheil Hassas Yeganeh <soheil@google.com> Signed-off-by: David S. Miller <davem@davemloft.net> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>		2020-05-20 08:18:38 +02:00
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acpi	x86: ACPI: fix CPU hotplug deadlock	2020-04-23 10:30:20 +02:00
asm-generic
clocksource
crypto
drm	drm/panel: make drm_panel.h self-contained	2020-01-27 14:51:01 +01:00
dt-bindings
keys	KEYS: Don't write out to userspace while holding key semaphore	2020-04-23 10:30:24 +02:00
kvm
linux	net: stricter validation of untrusted gso packets	2020-05-14 07:57:19 +02:00
math-emu
media	media: v4l2-device.h: Explicitly compare grp{id,mask} to zero in v4l2_device macros	2020-02-24 08:34:41 +01:00
memory
misc
net	tcp: fix SO_RCVLOWAT hangs with fat skbs	2020-05-20 08:18:38 +02:00
pcmcia
ras
rdma	RDMA/uverbs: Verify MR access flags	2020-02-14 16:33:23 -05:00
scsi	scsi: Revert "target: iscsi: Wait for all commands to finish before freeing a session"	2020-02-28 16:38:58 +01:00
soc
sound	ALSA: rawmidi: Avoid bit fields for state flags	2020-02-28 16:38:59 +01:00
target	scsi: target: fix hang when multiple threads try to destroy the same iscsi session	2020-04-21 09:03:11 +02:00
trace	svcrdma: Fix trace point use-after-free race	2020-05-02 17:25:51 +02:00
uapi	include/uapi/linux/swab.h: fix userspace breakage, use __BITS_PER_LONG for swap	2020-05-02 17:25:48 +02:00
video
xen