linux/include
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
..
acpi ACPI: NUMA: add missing include in acpi_numa.h 2017-07-24 22:27:43 +02:00
asm-generic mm: fix MADV_[FREE|DONTNEED] TLB flush miss problem 2017-08-10 15:54:07 -07:00
clocksource
crypto
drm i915, amd and some core fixes + mediatek color support 2017-07-13 11:26:18 -07:00
dt-bindings Merge branch 'upstream' of git://git.linux-mips.org/pub/scm/ralf/upstream-linus 2017-07-15 10:59:54 -07:00
keys
kvm KVM: arm/arm64: PMU: Fix overflow interrupt injection 2017-07-25 14:18:01 +01:00
linux net: core: Specify skb_pad()/skb_put_padto() SKB freeing 2017-08-23 20:33:49 -07:00
math-emu
media media: platform: davinci: drop VPFE_CMD_S_CCDC_RAW_PARAMS 2017-07-26 06:14:33 -04:00
memory
misc cxl: Export library to support IBM XSL 2017-07-03 23:07:03 +10:00
net tcp: fix refcnt leak with ebpf congestion control 2017-08-25 17:16:27 -07:00
pcmcia
ras
rdma IB/cma: Fix reference count leak when no ipv4 addresses are set 2017-07-20 11:24:13 -04:00
rxrpc
scsi Merge branch 'for-next' of git://git.kernel.org/pub/scm/linux/kernel/git/nab/target-pending 2017-07-13 14:27:32 -07:00
soc Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/net-next 2017-07-05 12:31:59 -07:00
sound ASoC: fix pcm-creation regression 2017-07-17 15:50:32 +01:00
target iscsi-target: Fix iscsi_np reset hung task during parallel delete 2017-08-06 14:41:41 -07:00
trace ext4: remove unused metadata accounting variables 2017-07-30 22:30:11 -04:00
uapi drm/msm: Remove __user from __u64 data types 2017-08-01 19:11:48 -04:00
video
xen xen/balloon: don't online new memory initially 2017-07-23 08:13:18 +02:00