bpf: verifier: teach the verifier to reason about the BPF_JSET instruction

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Some JITs (nfp) try to optimize code on their own.  It could make
sense in case of BPF_JSET instruction which is currently not interpreted
by the verifier, meaning for instance that dead could would not be
detected if it was under BPF_JSET branch.

Teach the verifier basics of BPF_JSET, JIT optimizations will be
removed shortly.

Signed-off-by: Jakub Kicinski <jakub.kicinski@netronome.com>
Reviewed-by: Jiong Wang <jiong.wang@netronome.com>
Acked-by: Edward Cree <ecree@solarflare.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>

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Jakub Kicinski 2018-12-19 22:13:04 -08:00 • committed by Daniel Borkmann

parent 5a8d5209ac

commit 960ea05656

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kernel/bpf/verifier.c

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