linux-stable/net
Sabrina Dubroca ebfa00c574 tcp: fix refcnt leak with ebpf congestion control
There are a few bugs around refcnt handling in the new BPF congestion
control setsockopt:

 - The new ca is assigned to icsk->icsk_ca_ops even in the case where we
   cannot get a reference on it. This would lead to a use after free,
   since that ca is going away soon.

 - Changing the congestion control case doesn't release the refcnt on
   the previous ca.

 - In the reinit case, we first leak a reference on the old ca, then we
   call tcp_reinit_congestion_control on the ca that we have just
   assigned, leading to deinitializing the wrong ca (->release of the
   new ca on the old ca's data) and releasing the refcount on the ca
   that we actually want to use.

This is visible by building (for example) BIC as a module and setting
net.ipv4.tcp_congestion_control=bic, and using tcp_cong_kern.c from
samples/bpf.

This patch fixes the refcount issues, and moves reinit back into tcp
core to avoid passing a ca pointer back to BPF.

Fixes: 91b5b21c7c ("bpf: Add support for changing congestion control")
Signed-off-by: Sabrina Dubroca <sd@queasysnail.net>
Acked-by: Lawrence Brakmo <brakmo@fb.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
2017-08-25 17:16:27 -07:00
..
6lowpan
9p Merge branch 'work.mount' of git://git.kernel.org/pub/scm/linux/kernel/git/viro/vfs 2017-07-15 12:00:42 -07:00
802 net: introduce __skb_put_[zero, data, u8] 2017-06-20 13:30:14 -04:00
8021q net: add netlink_ext_ack argument to rtnl_link_ops.validate 2017-06-26 23:13:22 -04:00
appletalk networking: make skb_push & __skb_push return void pointers 2017-06-16 11:48:40 -04:00
atm net, atm: convert eg_cache_entry.use from atomic_t to refcount_t 2017-07-04 22:35:16 +01:00
ax25 net, ax25: convert ax25_cb.refcount from atomic_t to refcount_t 2017-07-04 22:35:19 +01:00
batman-adv batman-adv: fix TT sync flag inconsistencies 2017-07-31 11:17:38 +02:00
bluetooth Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next 2017-07-05 12:31:59 -07:00
bpf
bridge net: bridge: fix dest lookup when vlan proto doesn't match 2017-07-14 08:19:23 -07:00
caif net: convert sock.sk_wmem_alloc from atomic_t to refcount_t 2017-07-01 07:39:08 -07:00
can networking: introduce and use skb_put_data() 2017-06-16 11:48:37 -04:00
ceph libceph: make RECOVERY_DELETES feature create a new interval 2017-08-01 16:46:45 +02:00
core tcp: fix refcnt leak with ebpf congestion control 2017-08-25 17:16:27 -07:00
dcb
dccp dccp: defer ccid_hc_tx_delete() at dismantle time 2017-08-16 14:26:26 -07:00
decnet net, decnet: convert dn_fib_info.fib_clntref from atomic_t to refcount_t 2017-07-04 22:35:15 +01:00
dns_resolver
dsa net: dsa: use consume_skb() 2017-08-23 22:13:34 -07:00
ethernet networking: make skb_push & __skb_push return void pointers 2017-06-16 11:48:40 -04:00
hsr net/hsr: Check skb_put_padto() return value 2017-08-22 13:40:23 -07:00
ieee802154 net: add netlink_ext_ack argument to rtnl_link_ops.validate 2017-06-26 23:13:22 -04:00
ife
ipv4 tcp: fix refcnt leak with ebpf congestion control 2017-08-25 17:16:27 -07:00
ipv6 ipv6: Fix may be used uninitialized warning in rt6_check 2017-08-25 17:05:27 -07:00
ipx net, ipx: convert ipx_route.refcnt from atomic_t to refcount_t 2017-07-04 22:35:17 +01:00
irda irda: do not leak initialized list.dev to userspace 2017-08-18 16:21:51 -07:00
iucv iucv: Convert sk_wmem_alloc accesses to refcount_t. 2017-07-03 02:31:22 -07:00
kcm net: convert sock.sk_wmem_alloc from atomic_t to refcount_t 2017-07-01 07:39:08 -07:00
key af_key: do not use GFP_KERNEL in atomic contexts 2017-08-14 22:18:12 -07:00
l2tp net, l2tp: convert l2tp_session.ref_count from atomic_t to refcount_t 2017-07-04 22:35:15 +01:00
l3mdev
lapb net, lapb: convert lapb_cb.refcnt from atomic_t to refcount_t 2017-07-04 22:35:16 +01:00
llc net, llc: convert llc_sap.refcnt from atomic_t to refcount_t 2017-07-04 22:35:15 +01:00
mac80211 mac80211: add api to start ba session timer expired flow 2017-08-09 09:49:42 +03:00
mac802154 net: Fix inconsistent teardown and release of private netdev state. 2017-06-07 15:53:24 -04:00
mpls mpls: fix uninitialized in_label var warning in mpls_getroute 2017-07-08 11:26:41 +01:00
ncsi networking: make skb_push & __skb_push return void pointers 2017-06-16 11:48:40 -04:00
netfilter Merge git://git.kernel.org/pub/scm/linux/kernel/git/pablo/nf 2017-08-24 11:49:19 -07:00
netlabel
netlink net: convert sock.sk_refcnt from atomic_t to refcount_t 2017-07-01 07:39:08 -07:00
netrom net, netrom: convert nr_node.refcount from atomic_t to refcount_t 2017-07-04 22:35:17 +01:00
nfc NFC: Add sockaddr length checks before accessing sa_family in bind handlers 2017-06-23 00:38:31 +02:00
openvswitch openvswitch: fix skb_panic due to the incorrect actions attrlen 2017-08-16 14:12:37 -07:00
packet packet: fix tp_reserve race in packet_set_ring 2017-08-10 09:52:12 -07:00
phonet net: convert sock.sk_refcnt from atomic_t to refcount_t 2017-07-01 07:39:08 -07:00
psample networking: make skb_put & friends return void pointers 2017-06-16 11:48:39 -04:00
qrtr networking: make skb_put & friends return void pointers 2017-06-16 11:48:39 -04:00
rds rds: Reintroduce statistics counting 2017-08-08 21:03:47 -07:00
rfkill net: rfkill: gpio: Switch to devm_acpi_dev_add_driver_gpios() 2017-06-13 11:07:51 +02:00
rose
rxrpc rxrpc: Fix oops when discarding a preallocated service call 2017-08-18 16:23:23 -07:00
sched net_sched: fix a refcount_t issue with noop_qdisc 2017-08-24 21:28:24 -07:00
sctp sctp: Avoid out-of-bounds reads from address storage 2017-08-23 22:35:15 -07:00
smc
strparser
sunrpc NFS client bugfixes for 4.13 2017-07-21 16:26:01 -07:00
switchdev net: switchdev: Change notifier chain to be atomic 2017-06-08 14:16:24 -04:00
tipc tipc: context imbalance at node read unlock 2017-08-24 21:54:34 -07:00
tls TLS: Fix length check in do_tls_getsockopt_tx() 2017-07-06 10:58:19 +01:00
unix datagram: When peeking datagrams with offset < 0 don't skip empty skbs 2017-08-18 15:12:54 -07:00
vmw_vsock net: manual clean code which call skb_put_[data:zero] 2017-06-20 13:30:15 -04:00
wimax
wireless netlink validation fixes for nl80211 2017-07-07 11:35:55 +01:00
x25 net, x25: convert x25_neigh.refcnt from atomic_t to refcount_t 2017-07-04 22:35:18 +01:00
xfrm xfrm: policy: check policy direction value 2017-08-03 10:15:22 +02:00
compat.c get_compat_bpf_fprog(): don't copyin field-by-field 2017-07-04 13:14:34 -04:00
Kconfig tls: kernel TLS support 2017-06-15 12:12:40 -04:00
Makefile tls: kernel TLS support 2017-06-15 12:12:40 -04:00
socket.c net/socket: fix type in assignment and trim long line 2017-07-24 14:17:01 -07:00
sysctl_net.c