On Thu, Nov 7, 2019 at 10:42 PM Alexei Starovoitov [off-list ref] wrote:

btf_resolve_helper_id() caching logic is a bit racy, since under root the
verifier can verify several programs in parallel. Fix it with READ/WRITE_ONCE.
Fix the type as well, since error is also recorded.

Fixes: a7658e1a4164 ("bpf: Check types of arguments passed into helpers")
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
---

looks good

Acked-by: Andrii Nakryiko <redacted>

 include/linux/bpf.h   |  5 +++--
 kernel/bpf/btf.c      | 26 +++++++++++++++++++++++++-
 kernel/bpf/verifier.c |  8 +++-----
 net/core/filter.c     |  2 +-
 4 files changed, 32 insertions(+), 9 deletions(-)

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