nfp: bpf: prevent integer overflow in nfp_bpf_event_output()

nfp: bpf: prevent integer overflow in nfp_bpf_event_output()

[ Upstream commit 16ebb6f5b6295c9688749862a39a4889c56227f8 ]

The "sizeof(struct cmsg_bpf_event) + pkt_size + data_size" math could
potentially have an integer wrapping bug on 32bit systems.  Check for
this and return an error.

Fixes: 9816dd35ecec ("nfp: bpf: perf event output helpers support")
Signed-off-by: Dan Carpenter <dan.carpenter@linaro.org>
Link: https://patch.msgid.link/6074805b-e78d-4b8a-bf05-e929b5377c28@stanley.mountain
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>