From: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
To: linux-kernel@vger.kernel.org
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
stable@vger.kernel.org, Guillaume Nault <gnault@redhat.com>,
Eric Dumazet <edumazet@google.com>,
"David S. Miller" <davem@davemloft.net>
Subject: [PATCH 5.4 19/37] tcp: Protect accesses to .ts_recent_stamp with {READ,WRITE}_ONCE()
Date: Tue, 17 Dec 2019 21:09:40 +0100 [thread overview]
Message-ID: <20191217200727.666289371@linuxfoundation.org> (raw)
In-Reply-To: <20191217200721.741054904@linuxfoundation.org>
From: Guillaume Nault <gnault@redhat.com>
[ Upstream commit 721c8dafad26ccfa90ff659ee19755e3377b829d ]
Syncookies borrow the ->rx_opt.ts_recent_stamp field to store the
timestamp of the last synflood. Protect them with READ_ONCE() and
WRITE_ONCE() since reads and writes aren't serialised.
Use of .rx_opt.ts_recent_stamp for storing the synflood timestamp was
introduced by a0f82f64e269 ("syncookies: remove last_synq_overflow from
struct tcp_sock"). But unprotected accesses were already there when
timestamp was stored in .last_synq_overflow.
Fixes: 1da177e4c3f4 ("Linux-2.6.12-rc2")
Signed-off-by: Guillaume Nault <gnault@redhat.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
include/net/tcp.h | 6 +++---
1 file changed, 3 insertions(+), 3 deletions(-)
--- a/include/net/tcp.h
+++ b/include/net/tcp.h
@@ -501,9 +501,9 @@ static inline void tcp_synq_overflow(con
}
}
- last_overflow = tcp_sk(sk)->rx_opt.ts_recent_stamp;
+ last_overflow = READ_ONCE(tcp_sk(sk)->rx_opt.ts_recent_stamp);
if (!time_between32(now, last_overflow, last_overflow + HZ))
- tcp_sk(sk)->rx_opt.ts_recent_stamp = now;
+ WRITE_ONCE(tcp_sk(sk)->rx_opt.ts_recent_stamp, now);
}
/* syncookies: no recent synqueue overflow on this listening socket? */
@@ -524,7 +524,7 @@ static inline bool tcp_synq_no_recent_ov
}
}
- last_overflow = tcp_sk(sk)->rx_opt.ts_recent_stamp;
+ last_overflow = READ_ONCE(tcp_sk(sk)->rx_opt.ts_recent_stamp);
/* If last_overflow <= jiffies <= last_overflow + TCP_SYNCOOKIE_VALID,
* then we're under synflood. However, we have to use
next prev parent reply other threads:[~2019-12-17 20:10 UTC|newest]
Thread overview: 48+ messages / expand[flat|nested] mbox.gz Atom feed top
2019-12-17 20:09 [PATCH 5.4 00/37] 5.4.5-stable review Greg Kroah-Hartman
2019-12-17 20:09 ` [PATCH 5.4 01/37] inet: protect against too small mtu values Greg Kroah-Hartman
2019-12-17 20:09 ` [PATCH 5.4 02/37] mqprio: Fix out-of-bounds access in mqprio_dump Greg Kroah-Hartman
2019-12-17 20:09 ` [PATCH 5.4 03/37] net: bridge: deny dev_set_mac_address() when unregistering Greg Kroah-Hartman
2019-12-17 20:09 ` [PATCH 5.4 04/37] net: dsa: fix flow dissection on Tx path Greg Kroah-Hartman
2019-12-17 20:09 ` [PATCH 5.4 05/37] net: ethernet: ti: cpsw: fix extra rx interrupt Greg Kroah-Hartman
2019-12-17 20:09 ` [PATCH 5.4 06/37] net: sched: fix dump qlen for sch_mq/sch_mqprio with NOLOCK subqueues Greg Kroah-Hartman
2019-12-17 20:09 ` [PATCH 5.4 07/37] net_sched: validate TCA_KIND attribute in tc_chain_tmplt_add() Greg Kroah-Hartman
2019-12-17 20:09 ` [PATCH 5.4 08/37] net-sysfs: Call dev_hold always in netdev_queue_add_kobject Greg Kroah-Hartman
2019-12-17 20:09 ` [PATCH 5.4 09/37] net: thunderx: start phy before starting autonegotiation Greg Kroah-Hartman
2019-12-17 20:09 ` [PATCH 5.4 10/37] net/tls: Fix return values to avoid ENOTSUPP Greg Kroah-Hartman
2019-12-17 20:09 ` [PATCH 5.4 11/37] openvswitch: support asymmetric conntrack Greg Kroah-Hartman
2019-12-17 20:09 ` [PATCH 5.4 12/37] tcp: md5: fix potential overestimation of TCP option space Greg Kroah-Hartman
2019-12-17 20:09 ` [PATCH 5.4 13/37] tipc: fix ordering of tipc module init and exit routine Greg Kroah-Hartman
2019-12-17 20:09 ` [PATCH 5.4 14/37] net/mlx5e: Query global pause state before setting prio2buffer Greg Kroah-Hartman
2019-12-17 20:09 ` [PATCH 5.4 15/37] net: ipv6: add net argument to ip6_dst_lookup_flow Greg Kroah-Hartman
2019-12-17 20:09 ` [PATCH 5.4 16/37] net: ipv6_stub: use ip6_dst_lookup_flow instead of ip6_dst_lookup Greg Kroah-Hartman
2019-12-17 20:09 ` [PATCH 5.4 17/37] tcp: fix rejected syncookies due to stale timestamps Greg Kroah-Hartman
2019-12-17 20:09 ` [PATCH 5.4 18/37] tcp: tighten acceptance of ACKs not matching a child socket Greg Kroah-Hartman
2019-12-17 20:09 ` Greg Kroah-Hartman [this message]
2019-12-17 20:09 ` [PATCH 5.4 20/37] net: core: rename indirect block ingress cb function Greg Kroah-Hartman
2019-12-17 20:09 ` [PATCH 5.4 21/37] net: sched: allow indirect blocks to bind to clsact in TC Greg Kroah-Hartman
2019-12-17 20:09 ` [PATCH 5.4 22/37] cls_flower: Fix the behavior using port ranges with hw-offload Greg Kroah-Hartman
2019-12-17 20:09 ` [PATCH 5.4 23/37] gre: refetch erspan header from skb->data after pskb_may_pull() Greg Kroah-Hartman
2019-12-17 20:09 ` [PATCH 5.4 24/37] Fixed updating of ethertype in function skb_mpls_pop Greg Kroah-Hartman
2019-12-17 20:09 ` [PATCH 5.4 25/37] hsr: fix a NULL pointer dereference in hsr_dev_xmit() Greg Kroah-Hartman
2019-12-17 20:09 ` [PATCH 5.4 26/37] net: Fixed updating of ethertype in skb_mpls_push() Greg Kroah-Hartman
2019-12-17 20:09 ` [PATCH 5.4 27/37] net/mlx5e: Fix TXQ indices to be sequential Greg Kroah-Hartman
2019-12-17 20:09 ` [PATCH 5.4 28/37] act_ct: support asymmetric conntrack Greg Kroah-Hartman
2019-12-17 20:09 ` [PATCH 5.4 29/37] net/mlx5e: Fix SFF 8472 eeprom length Greg Kroah-Hartman
2019-12-17 20:09 ` [PATCH 5.4 30/37] net/mlx5e: Fix freeing flow with kfree() and not kvfree() Greg Kroah-Hartman
2019-12-17 20:09 ` [PATCH 5.4 31/37] net/mlx5e: Fix translation of link mode into speed Greg Kroah-Hartman
2019-12-17 20:09 ` [PATCH 5.4 32/37] net/mlx5e: ethtool, Fix analysis of speed setting Greg Kroah-Hartman
2019-12-17 20:09 ` [PATCH 5.4 33/37] page_pool: do not release pool until inflight == 0 Greg Kroah-Hartman
2019-12-17 20:09 ` [PATCH 5.4 34/37] xdp: obtain the mem_id mutex before trying to remove an entry Greg Kroah-Hartman
2019-12-17 20:09 ` [PATCH 5.4 35/37] ionic: keep users rss hash across lif reset Greg Kroah-Hartman
2019-12-17 20:09 ` [PATCH 5.4 36/37] net: mscc: ocelot: unregister the PTP clock on deinit Greg Kroah-Hartman
2019-12-17 20:09 ` [PATCH 5.4 37/37] r8169: add missing RX enabling for WoL on RTL8125 Greg Kroah-Hartman
2019-12-18 10:24 ` [PATCH 5.4 00/37] 5.4.5-stable review Jon Hunter
2019-12-18 14:34 ` Greg Kroah-Hartman
2019-12-18 14:22 ` Naresh Kamboju
2019-12-18 14:35 ` Greg Kroah-Hartman
2019-12-18 14:48 ` Guenter Roeck
2019-12-18 14:53 ` Greg Kroah-Hartman
2019-12-18 20:59 ` shuah
2019-12-19 8:44 ` Greg Kroah-Hartman
2019-12-18 21:02 ` Geert Uytterhoeven
2019-12-19 8:45 ` Greg Kroah-Hartman
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