linux/include
John Fastabend 9635720b7c bpf, sockmap: Fix memleak on ingress msg enqueue
If backlog handler is running during a tear down operation we may enqueue
data on the ingress msg queue while tear down is trying to free it.

 sk_psock_backlog()
   sk_psock_handle_skb()
     skb_psock_skb_ingress()
       sk_psock_skb_ingress_enqueue()
         sk_psock_queue_msg(psock,msg)
                                           spin_lock(ingress_lock)
                                            sk_psock_zap_ingress()
                                             _sk_psock_purge_ingerss_msg()
                                              _sk_psock_purge_ingress_msg()
                                            -- free ingress_msg list --
                                           spin_unlock(ingress_lock)
           spin_lock(ingress_lock)
           list_add_tail(msg,ingress_msg) <- entry on list with no one
                                             left to free it.
           spin_unlock(ingress_lock)

To fix we only enqueue from backlog if the ENABLED bit is set. The tear
down logic clears the bit with ingress_lock set so we wont enqueue the
msg in the last step.

Fixes: 799aa7f98d ("skmsg: Avoid lock_sock() in sk_psock_backlog()")
Signed-off-by: John Fastabend <john.fastabend@gmail.com>
Signed-off-by: Andrii Nakryiko <andrii@kernel.org>
Acked-by: Jakub Sitnicki <jakub@cloudflare.com>
Acked-by: Martin KaFai Lau <kafai@fb.com>
Link: https://lore.kernel.org/bpf/20210727160500.1713554-4-john.fastabend@gmail.com
2021-07-27 14:55:30 -07:00
..
acpi IOMMU Updates for Linux v5.14 2021-07-02 13:22:47 -07:00
asm-generic This pull request contains the following changes for UML: 2021-07-09 10:19:13 -07:00
clocksource
crypto
drm
dt-bindings ARM: Drivers for 5.14 2021-07-10 09:46:20 -07:00
keys
kunit linux-kselftest-kunit-fixes-5.14-rc1 2021-07-02 12:58:26 -07:00
kvm
linux bpf, sockmap: Fix memleak on ingress msg enqueue 2021-07-27 14:55:30 -07:00
math-emu
media
memory
misc
net Networking fixes for 5.14-rc2, including fixes from bpf and netfilter. 2021-07-14 09:24:32 -07:00
pcmcia
ras
rdma
scsi SCSI misc on 20210702 2021-07-02 15:14:36 -07:00
soc ARM: Drivers for 5.14 2021-07-10 09:46:20 -07:00
sound ASoC: Updates for v5.14 2021-07-01 08:36:12 +02:00
target
trace net_sched: introduce tracepoint trace_qdisc_enqueue() 2021-07-15 10:32:38 -07:00
uapi Networking fixes for 5.14-rc2, including fixes from bpf and netfilter. 2021-07-14 09:24:32 -07:00
vdso
video
xen xen: sync include/xen/interface/io/ring.h with Xen's newest version 2021-07-05 09:49:45 +02:00