[SRU B/D/E/F/focal:linux-oem-5.6 0/2] cgroup refcount is bogus when cgroup_sk_alloc is disabled
Thadeu Lima de Souza Cascardo
cascardo at canonical.com
Mon Jul 27 13:28:38 UTC 2020
This is a followup from LP: #1886668.
When net_prio and net_cls cgroups are used, cgroup refcount is bogus, as it's
not incremented anymore, but decremented when sockets are closed.
This might lead to crashes possibly because of use-after-free when packets are
received as shown in LP #1886668.
Ran reproducer from comment #2.
We could break the use of cgroup bpf. The use of cgroup bpf looks to still be
working from the reproducer.
Cong Wang (2):
cgroup: fix cgroup_sk_alloc() for sk_clone_lock()
cgroup: Fix sock_cgroup_data on big-endian.
include/linux/cgroup-defs.h | 8 ++++++--
include/linux/cgroup.h | 4 +++-
kernel/cgroup/cgroup.c | 29 ++++++++++++++++++-----------
net/core/sock.c | 2 +-
4 files changed, 28 insertions(+), 15 deletions(-)
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