diff options
| author | Eduard Zingerman <eddyz87@gmail.com> | 2025-06-11 13:08:31 -0700 |
|---|---|---|
| committer | Alexei Starovoitov <ast@kernel.org> | 2025-06-12 16:52:43 -0700 |
| commit | dfb2d4c64b82ac1e7a03e0b28b4326458705d26f (patch) | |
| tree | fd8f75823c550f9c5dcaf3464ca88355242db0d0 | |
| parent | 23b37d616565c89dd202febc68d926345727d092 (diff) | |
bpf: set 'changed' status if propagate_liveness() did any updates
Add an out parameter to `propagate_liveness()` to record whether any
new liveness bits were set during its execution.
Signed-off-by: Eduard Zingerman <eddyz87@gmail.com>
Link: https://lore.kernel.org/r/20250611200836.4135542-6-eddyz87@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
| -rw-r--r-- | kernel/bpf/verifier.c | 9 |
1 files changed, 7 insertions, 2 deletions
diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c index b00769ceef8c..e49bdce05049 100644 --- a/kernel/bpf/verifier.c +++ b/kernel/bpf/verifier.c @@ -18856,12 +18856,15 @@ static int propagate_liveness_reg(struct bpf_verifier_env *env, */ static int propagate_liveness(struct bpf_verifier_env *env, const struct bpf_verifier_state *vstate, - struct bpf_verifier_state *vparent) + struct bpf_verifier_state *vparent, + bool *changed) { struct bpf_reg_state *state_reg, *parent_reg; struct bpf_func_state *state, *parent; int i, frame, err = 0; + bool tmp; + changed = changed ?: &tmp; if (vparent->curframe != vstate->curframe) { WARN(1, "propagate_live: parent frame %d current frame %d\n", vparent->curframe, vstate->curframe); @@ -18880,6 +18883,7 @@ static int propagate_liveness(struct bpf_verifier_env *env, &parent_reg[i]); if (err < 0) return err; + *changed |= err > 0; if (err == REG_LIVE_READ64) mark_insn_zext(env, &parent_reg[i]); } @@ -18891,6 +18895,7 @@ static int propagate_liveness(struct bpf_verifier_env *env, state_reg = &state->stack[i].spilled_ptr; err = propagate_liveness_reg(env, state_reg, parent_reg); + *changed |= err > 0; if (err < 0) return err; } @@ -19266,7 +19271,7 @@ hit: * they'll be immediately forgotten as we're pruning * this state and will pop a new one. */ - err = propagate_liveness(env, &sl->state, cur); + err = propagate_liveness(env, &sl->state, cur, NULL); /* if previous state reached the exit with precision and * current state is equivalent to it (except precision marks) |