diff options
| -rw-r--r-- | kernel/bpf/verifier.c | 21 |
1 files changed, 9 insertions, 12 deletions
diff --git a/kernel/bpf/verifier.c b/kernel/bpf/verifier.c index 5133d0a5b0cb..6431b994b3f6 100644 --- a/kernel/bpf/verifier.c +++ b/kernel/bpf/verifier.c @@ -13057,18 +13057,19 @@ next: } } +static bool regs_exact(const struct bpf_reg_state *rold, + const struct bpf_reg_state *rcur) +{ + return memcmp(rold, rcur, offsetof(struct bpf_reg_state, parent)) == 0; +} + /* Returns true if (rold safe implies rcur safe) */ static bool regsafe(struct bpf_verifier_env *env, struct bpf_reg_state *rold, struct bpf_reg_state *rcur, struct bpf_id_pair *idmap) { - bool equal; - if (!(rold->live & REG_LIVE_READ)) /* explored state didn't use this */ return true; - - equal = memcmp(rold, rcur, offsetof(struct bpf_reg_state, parent)) == 0; - if (rold->type == NOT_INIT) /* explored state can't have used this */ return true; @@ -13101,7 +13102,7 @@ static bool regsafe(struct bpf_verifier_env *env, struct bpf_reg_state *rold, switch (base_type(rold->type)) { case SCALAR_VALUE: - if (equal) + if (regs_exact(rold, rcur)) return true; if (env->explore_alu_limits) return false; @@ -13144,15 +13145,11 @@ static bool regsafe(struct bpf_verifier_env *env, struct bpf_reg_state *rold, /* two stack pointers are equal only if they're pointing to * the same stack frame, since fp-8 in foo != fp-8 in bar */ - return equal && rold->frameno == rcur->frameno; + return regs_exact(rold, rcur) && rold->frameno == rcur->frameno; default: /* Only valid matches are exact, which memcmp() */ - return equal; + return regs_exact(rold, rcur); } - - /* Shouldn't get here; if we do, say it's not safe */ - WARN_ON_ONCE(1); - return false; } static bool stacksafe(struct bpf_verifier_env *env, struct bpf_func_state *old, |