diff options
| author | Eduard Zingerman <eddyz87@gmail.com> | 2025-06-11 13:08:28 -0700 |
|---|---|---|
| committer | Alexei Starovoitov <ast@kernel.org> | 2025-06-12 16:52:42 -0700 |
| commit | 13f843c0177eeb367ac63467c538046b90785583 (patch) | |
| tree | bd13afd48407bd4f5681090dcb1ad635223bc69f /kernel | |
| parent | 96c6aa4c63af0bb0675c41b3e61a2fc7f6fed998 (diff) | |
bpf: frame_insn_idx() utility function
A function to return IP for a given frame in a call stack of a state.
Will be used by a next patch.
The `state->insn_idx = env->insn_idx;` assignment in the do_check()
allows to use frame_insn_idx with env->cur_state.
At the moment bpf_verifier_state->insn_idx is set when new cached
state is added in is_state_visited() and accessed only in the contexts
when the state is already in the cache. Hence this assignment does not
change verifier behaviour.
Signed-off-by: Eduard Zingerman <eddyz87@gmail.com>
Link: https://lore.kernel.org/r/20250611200836.4135542-3-eddyz87@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Diffstat (limited to 'kernel')
| -rw-r--r-- | kernel/bpf/verifier.c | 13 |
1 files changed, 10 insertions, 3 deletions
diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c index 75e4f6544b2a..ebb98a78c919 100644 --- a/kernel/bpf/verifier.c +++ b/kernel/bpf/verifier.c @@ -1964,6 +1964,14 @@ static void update_loop_entry(struct bpf_verifier_env *env, } } +/* Return IP for a given frame in a call stack */ +static u32 frame_insn_idx(struct bpf_verifier_state *st, u32 frame) +{ + return frame == st->curframe + ? st->insn_idx + : st->frame[frame + 1]->callsite; +} + static void update_branch_counts(struct bpf_verifier_env *env, struct bpf_verifier_state *st) { struct bpf_verifier_state_list *sl = NULL, *parent_sl; @@ -18790,9 +18798,7 @@ static bool states_equal(struct bpf_verifier_env *env, * and all frame states need to be equivalent */ for (i = 0; i <= old->curframe; i++) { - insn_idx = i == old->curframe - ? env->insn_idx - : old->frame[i + 1]->callsite; + insn_idx = frame_insn_idx(old, i); if (old->frame[i]->callsite != cur->frame[i]->callsite) return false; if (!func_states_equal(env, old->frame[i], cur->frame[i], insn_idx, exact)) @@ -19687,6 +19693,7 @@ static int do_check(struct bpf_verifier_env *env) } state->last_insn_idx = env->prev_insn_idx; + state->insn_idx = env->insn_idx; if (is_prune_point(env, env->insn_idx)) { err = is_state_visited(env, env->insn_idx); |