diff options
| author | Roman Gushchin <guro@fb.com> | 2018-07-13 12:41:11 -0700 |
|---|---|---|
| committer | Daniel Borkmann <daniel@iogearbox.net> | 2018-07-18 15:01:54 +0200 |
| commit | 3960f4fd6585608e8cc285d9665821985494e147 (patch) | |
| tree | 3123a66bc1149da0330645b49bb331a482669318 /kernel/bpf | |
| parent | d29ab6e1fa21ebc2a8a771015dd9e0e5d4e28dc1 (diff) | |
| download | linux-3960f4fd6585608e8cc285d9665821985494e147.tar.bz2 | |
bpf: fix rcu annotations in compute_effective_progs()
The progs local variable in compute_effective_progs() is marked
as __rcu, which is not correct. This is a local pointer, which
is initialized by bpf_prog_array_alloc(), which also now
returns a generic non-rcu pointer.
The real rcu-protected pointer is *array (array is a pointer
to an RCU-protected pointer), so the assignment should be performed
using rcu_assign_pointer().
Fixes: 324bda9e6c5a ("bpf: multi program support for cgroup+bpf")
Signed-off-by: Roman Gushchin <guro@fb.com>
Cc: Alexei Starovoitov <ast@kernel.org>
Cc: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Diffstat (limited to 'kernel/bpf')
| -rw-r--r-- | kernel/bpf/cgroup.c | 7 |
1 files changed, 3 insertions, 4 deletions
diff --git a/kernel/bpf/cgroup.c b/kernel/bpf/cgroup.c index 3d83ee7df381..badabb0b435c 100644 --- a/kernel/bpf/cgroup.c +++ b/kernel/bpf/cgroup.c @@ -95,7 +95,7 @@ static int compute_effective_progs(struct cgroup *cgrp, enum bpf_attach_type type, struct bpf_prog_array __rcu **array) { - struct bpf_prog_array __rcu *progs; + struct bpf_prog_array *progs; struct bpf_prog_list *pl; struct cgroup *p = cgrp; int cnt = 0; @@ -120,13 +120,12 @@ static int compute_effective_progs(struct cgroup *cgrp, &p->bpf.progs[type], node) { if (!pl->prog) continue; - rcu_dereference_protected(progs, 1)-> - progs[cnt++] = pl->prog; + progs->progs[cnt++] = pl->prog; } p = cgroup_parent(p); } while (p); - *array = progs; + rcu_assign_pointer(*array, progs); return 0; } |