Commit 95253dc7 authored by Jakub Kicinski's avatar Jakub Kicinski
Browse files

Merge branch 'tcp-better-memory-control-for-not-yet-accepted-sockets' 

Eric Dumazet says:

====================
tcp: better memory control for not-yet-accepted sockets

Address a possible OOM condition caused by a recent change.

Add a new packetdrill test checking the expected behavior.
====================

Link: https://patch.msgid.link/20250707213900.1543248-1-edumazet@google.com


Signed-off-by: default avatarJakub Kicinski <kuba@kernel.org>
parents ffdde7bf b939c074

net/ipv4/tcp_input.c

+3 −1
Original line number Diff line number Diff line
@@ -5181,6 +5181,8 @@ static void tcp_data_queue_ofo(struct sock *sk, struct sk_buff *skb) 
		skb_condense(skb);

		skb_set_owner_r(skb, sk);

	}

	/* do not grow rcvbuf for not-yet-accepted or orphaned sockets. */

	if (sk->sk_socket)

		tcp_rcvbuf_grow(sk);

}

tools/testing/selftests/net/packetdrill/tcp_ooo-before-and-after-accept.pkt

0 → 100644
+53 −0
Original line number Diff line number Diff line 
// SPDX-License-Identifier: GPL-2.0



--mss=1000



`./defaults.sh

sysctl -q net.ipv4.tcp_rmem="4096 131072 $((32*1024*1024))"`



// Test that a not-yet-accepted socket does not change

// its initial sk_rcvbuf (tcp_rmem[1]) when receiving ooo packets.



   +0 socket(..., SOCK_STREAM, IPPROTO_TCP) = 3

   +0 setsockopt(3, SOL_SOCKET, SO_REUSEADDR, [1], 4) = 0

   +0 bind(3, ..., ...) = 0

   +0 listen(3, 1) = 0



   +0 < S 0:0(0) win 65535 <mss 1000,nop,nop,sackOK,nop,wscale 7>

   +0 > S. 0:0(0) ack 1 <mss 1460,nop,nop,sackOK,nop,wscale 10>

  +.1 < . 1:1(0) ack 1 win 257

  +0  < . 2001:41001(39000) ack 1 win 257

  +0  > . 1:1(0) ack 1 <nop,nop,sack 2001:41001>

  +0  < . 41001:101001(60000) ack 1 win 257

  +0  > . 1:1(0) ack 1 <nop,nop,sack 2001:101001>

  +0  < . 1:1001(1000) ack 1 win 257

  +0  > . 1:1(0) ack 1001 <nop,nop,sack 2001:101001>

  +0  < . 1001:2001(1000) ack 1 win 257

  +0  > . 1:1(0) ack 101001



  +0 accept(3, ..., ...) = 4



  +0 %{ assert SK_MEMINFO_RCVBUF == 131072, SK_MEMINFO_RCVBUF }%



  +0 close(4) = 0

  +0 close(3) = 0



// Test that ooo packets for accepted sockets do increase sk_rcvbuf

   +0 socket(..., SOCK_STREAM, IPPROTO_TCP) = 3

   +0 setsockopt(3, SOL_SOCKET, SO_REUSEADDR, [1], 4) = 0

   +0 bind(3, ..., ...) = 0

   +0 listen(3, 1) = 0



   +0 < S 0:0(0) win 65535 <mss 1000,nop,nop,sackOK,nop,wscale 7>

   +0 > S. 0:0(0) ack 1 <mss 1460,nop,nop,sackOK,nop,wscale 10>

  +.1 < . 1:1(0) ack 1 win 257



   +0 accept(3, ..., ...) = 4



  +0  < . 2001:41001(39000) ack 1 win 257

  +0  > . 1:1(0) ack 1 <nop,nop,sack 2001:41001>

  +0  < . 41001:101001(60000) ack 1 win 257

  +0  > . 1:1(0) ack 1 <nop,nop,sack 2001:101001>



  +0 %{ assert SK_MEMINFO_RCVBUF > 131072, SK_MEMINFO_RCVBUF }%