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| author | Alexei Starovoitov <ast@fb.com> | 2017-12-01 08:31:36 +0300 |
|---|---|---|
| committer | Daniel Borkmann <daniel@iogearbox.net> | 2017-12-01 13:25:10 +0300 |
| commit | 4e92024a48ecbd06fba3ccfb2174abd3d2f54a83 (patch) | |
| tree | b030efd3163882d2a917529dbc2e361ae9b22840 | |
| parent | 12a3cc8424fe1237aaeb982dec4f0914ddd22f3e (diff) | |
| download | linux-4e92024a48ecbd06fba3ccfb2174abd3d2f54a83.tar.xz | |
bpf: print liveness info to verifier log
let verifier print register and stack liveness information
into verifier log
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
| -rw-r--r-- | kernel/bpf/verifier.c | 24 |
1 files changed, 20 insertions, 4 deletions
diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c index 71a9429fdbb5..f7229390c279 100644 --- a/kernel/bpf/verifier.c +++ b/kernel/bpf/verifier.c @@ -216,6 +216,17 @@ static const char * const reg_type_str[] = { [PTR_TO_PACKET_END] = "pkt_end", }; +static void print_liveness(struct bpf_verifier_env *env, + enum bpf_reg_liveness live) +{ + if (live & (REG_LIVE_READ | REG_LIVE_WRITTEN)) + verbose(env, "_"); + if (live & REG_LIVE_READ) + verbose(env, "r"); + if (live & REG_LIVE_WRITTEN) + verbose(env, "w"); +} + static void print_verifier_state(struct bpf_verifier_env *env, struct bpf_verifier_state *state) { @@ -228,7 +239,9 @@ static void print_verifier_state(struct bpf_verifier_env *env, t = reg->type; if (t == NOT_INIT) continue; - verbose(env, " R%d=%s", i, reg_type_str[t]); + verbose(env, " R%d", i); + print_liveness(env, reg->live); + verbose(env, "=%s", reg_type_str[t]); if ((t == SCALAR_VALUE || t == PTR_TO_STACK) && tnum_is_const(reg->var_off)) { /* reg->off should be 0 for SCALAR_VALUE */ @@ -277,10 +290,13 @@ static void print_verifier_state(struct bpf_verifier_env *env, } } for (i = 0; i < state->allocated_stack / BPF_REG_SIZE; i++) { - if (state->stack[i].slot_type[0] == STACK_SPILL) - verbose(env, " fp%d=%s", - (-i - 1) * BPF_REG_SIZE, + if (state->stack[i].slot_type[0] == STACK_SPILL) { + verbose(env, " fp%d", + (-i - 1) * BPF_REG_SIZE); + print_liveness(env, state->stack[i].spilled_ptr.live); + verbose(env, "=%s", reg_type_str[state->stack[i].spilled_ptr.type]); + } } verbose(env, "\n"); } |