Star64_linux/net/ipv4
Eric Dumazet b617158dc0 tcp: be more careful in tcp_fragment()
Some applications set tiny SO_SNDBUF values and expect
TCP to just work. Recent patches to address CVE-2019-11478
broke them in case of losses, since retransmits might
be prevented.

We should allow these flows to make progress.

This patch allows the first and last skb in retransmit queue
to be split even if memory limits are hit.

It also adds the some room due to the fact that tcp_sendmsg()
and tcp_sendpage() might overshoot sk_wmem_queued by about one full
TSO skb (64KB size). Note this allowance was already present
in stable backports for kernels < 4.15

Note for < 4.15 backports :
 tcp_rtx_queue_tail() will probably look like :

static inline struct sk_buff *tcp_rtx_queue_tail(const struct sock *sk)
{
	struct sk_buff *skb = tcp_send_head(sk);

	return skb ? tcp_write_queue_prev(sk, skb) : tcp_write_queue_tail(sk);
}

Fixes: f070ef2ac6 ("tcp: tcp_fragment() should apply sane memory limits")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: Andrew Prout <aprout@ll.mit.edu>
Tested-by: Andrew Prout <aprout@ll.mit.edu>
Tested-by: Jonathan Lemon <jonathan.lemon@gmail.com>
Tested-by: Michal Kubecek <mkubecek@suse.cz>
Acked-by: Neal Cardwell <ncardwell@google.com>
Acked-by: Yuchung Cheng <ycheng@google.com>
Acked-by: Christoph Paasch <cpaasch@apple.com>
Cc: Jonathan Looney <jtl@netflix.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2019-07-21 20:41:24 -07:00
..
bpfilter
netfilter netfilter: synproxy: fix erroneous tcp mss option 2019-07-16 13:17:01 +02:00
af_inet.c ipv4: use indirect call wrappers for {tcp, udp}_{recv, send}msg() 2019-07-03 13:51:54 -07:00
ah4.c
arp.c
cipso_ipv4.c
datagram.c
devinet.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2019-07-08 19:48:57 -07:00
esp4.c xfrm: remove get_mtu indirection from xfrm_type 2019-07-01 06:16:40 +02:00
esp4_offload.c Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/klassert/ipsec-next 2019-07-05 15:01:15 -07:00
fib_frontend.c fib: relax source validation check for loopback packets 2019-07-17 15:23:39 -07:00
fib_lookup.h
fib_notifier.c
fib_rules.c
fib_semantics.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2019-06-17 20:20:36 -07:00
fib_trie.c ipv4: Fix off-by-one in route dump counter without netlink strict checking 2019-07-02 14:06:47 -07:00
fou.c
gre_demux.c net: remove unused parameter from skb_checksum_try_convert 2019-07-05 15:30:36 -07:00
gre_offload.c
icmp.c
igmp.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2019-07-08 19:48:57 -07:00
inet_connection_sock.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2019-06-22 08:59:24 -04:00
inet_diag.c
inet_fragment.c inet: fix various use-after-free in defrags units 2019-06-19 11:37:47 -04:00
inet_hashtables.c
inet_timewait_sock.c
inetpeer.c
ip_forward.c
ip_fragment.c inet: fix various use-after-free in defrags units 2019-06-19 11:37:47 -04:00
ip_gre.c
ip_input.c
ip_options.c netfilter: nf_tables: add support for matching IPv4 options 2019-06-21 18:35:51 +02:00
ip_output.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2019-06-27 21:06:39 -07:00
ip_sockglue.c
ip_tunnel.c
ip_tunnel_core.c ip_tunnel: allow not to count pkts on tstats by setting skb's dev to NULL 2019-06-18 20:48:45 -04:00
ip_vti.c
ipcomp.c Merge branch 'master' of git://git.kernel.org/pub/scm/linux/kernel/git/klassert/ipsec-next 2019-07-05 15:01:15 -07:00
ipconfig.c
ipip.c
ipmr.c
ipmr_base.c
Kconfig
Makefile
metrics.c
netfilter.c
netlink.c
nexthop.c
ping.c
proc.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2019-06-17 20:20:36 -07:00
protocol.c
raw.c ipv4: Use return value of inet_iif() for __raw_v4_lookup in the while loop 2019-06-25 12:46:02 -07:00
raw_diag.c net: don't warn in inet diag when IPV6 is disabled 2019-07-03 11:26:35 -07:00
route.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2019-07-08 19:48:57 -07:00
syncookies.c
sysctl_net_ipv4.c proc/sysctl: add shared variables for range check 2019-07-18 17:08:07 -07:00
tcp.c tcp: fix tcp_set_congestion_control() use from bpf hook 2019-07-18 20:33:48 -07:00
tcp_bbr.c
tcp_bic.c
tcp_bpf.c
tcp_cdg.c
tcp_cong.c tcp: fix tcp_set_congestion_control() use from bpf hook 2019-07-18 20:33:48 -07:00
tcp_cubic.c
tcp_dctcp.c
tcp_dctcp.h
tcp_diag.c
tcp_fastopen.c net: fastopen: robustness and endianness fixes for SipHash 2019-06-22 16:30:37 -07:00
tcp_highspeed.c
tcp_htcp.c
tcp_hybla.c
tcp_illinois.c
tcp_input.c bpf: add BPF_CGROUP_SOCK_OPS callback that is executed on every RTT 2019-07-03 16:52:01 +02:00
tcp_ipv4.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2019-06-17 20:20:36 -07:00
tcp_lp.c
tcp_metrics.c
tcp_minisocks.c
tcp_nv.c
tcp_offload.c
tcp_output.c tcp: be more careful in tcp_fragment() 2019-07-21 20:41:24 -07:00
tcp_rate.c
tcp_recovery.c
tcp_scalable.c
tcp_timer.c tcp: enforce tcp_min_snd_mss in tcp_mtu_probing() 2019-06-15 18:47:31 -07:00
tcp_ulp.c
tcp_vegas.c
tcp_vegas.h
tcp_veno.c
tcp_westwood.c
tcp_yeah.c
tunnel4.c
udp.c udp: Fix typo in net/ipv4/udp.c 2019-07-18 11:49:46 -07:00
udp_diag.c
udp_impl.h
udp_offload.c Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net 2019-06-22 08:59:24 -04:00
udp_tunnel.c
udplite.c
xfrm4_input.c
xfrm4_output.c
xfrm4_policy.c
xfrm4_protocol.c
xfrm4_state.c
xfrm4_tunnel.c