diff options
| -rw-r--r-- | kernel/bpf/verifier.c | 16 | ||||
| -rw-r--r-- | tools/testing/selftests/bpf/verifier/precise.c | 9 |
2 files changed, 18 insertions, 7 deletions
diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c index 13bbaa2485fc..899122832d8e 100644 --- a/kernel/bpf/verifier.c +++ b/kernel/bpf/verifier.c @@ -3806,7 +3806,7 @@ static int __mark_chain_precision(struct bpf_verifier_env *env, int regno) err = backtrack_insn(env, i, bt); } if (err == -ENOTSUPP) { - mark_all_scalars_precise(env, st); + mark_all_scalars_precise(env, env->cur_state); bt_reset(bt); return 0; } else if (err) { @@ -3868,7 +3868,7 @@ static int __mark_chain_precision(struct bpf_verifier_env *env, int regno) * fp-8 and it's "unallocated" stack space. * In such case fallback to conservative. */ - mark_all_scalars_precise(env, st); + mark_all_scalars_precise(env, env->cur_state); bt_reset(bt); return 0; } @@ -3896,11 +3896,21 @@ static int __mark_chain_precision(struct bpf_verifier_env *env, int regno) } if (bt_empty(bt)) - break; + return 0; last_idx = st->last_insn_idx; first_idx = st->first_insn_idx; } + + /* if we still have requested precise regs or slots, we missed + * something (e.g., stack access through non-r10 register), so + * fallback to marking all precise + */ + if (!bt_empty(bt)) { + mark_all_scalars_precise(env, env->cur_state); + bt_reset(bt); + } + return 0; } diff --git a/tools/testing/selftests/bpf/verifier/precise.c b/tools/testing/selftests/bpf/verifier/precise.c index 77ea018582c5..b8c0aae8e7ec 100644 --- a/tools/testing/selftests/bpf/verifier/precise.c +++ b/tools/testing/selftests/bpf/verifier/precise.c @@ -159,8 +159,9 @@ mark_precise: frame0: regs=r4 stack= before 3\ mark_precise: frame0: regs= stack=-8 before 2\ mark_precise: frame0: falling back to forcing all scalars precise\ + force_precise: frame0: forcing r0 to be precise\ mark_precise: frame0: last_idx 5 first_idx 5\ - mark_precise: frame0: parent state regs=r0 stack=:", + mark_precise: frame0: parent state regs= stack=:", .result = VERBOSE_ACCEPT, .retval = -1, }, @@ -187,10 +188,10 @@ mark_precise: frame0: falling back to forcing all scalars precise\ force_precise: frame0: forcing r0 to be precise\ force_precise: frame0: forcing r0 to be precise\ + force_precise: frame0: forcing r0 to be precise\ + force_precise: frame0: forcing r0 to be precise\ mark_precise: frame0: last_idx 6 first_idx 6\ - mark_precise: frame0: parent state regs=r0 stack=:\ - mark_precise: frame0: last_idx 5 first_idx 3\ - mark_precise: frame0: regs=r0 stack= before 5", + mark_precise: frame0: parent state regs= stack=:", .result = VERBOSE_ACCEPT, .retval = -1, }, |