Commit c7a429df authored by Alexei Starovoitov's avatar Alexei Starovoitov Committed by Kamal Mostafa

bpf/verifier: reject invalid LD_ABS | BPF_DW instruction

commit d82bccc6 upstream.

verifier must check for reserved size bits in instruction opcode and
reject BPF_LD | BPF_ABS | BPF_DW and BPF_LD | BPF_IND | BPF_DW instructions,
otherwise interpreter will WARN_RATELIMIT on them during execution.

Fixes: ddd872bc ("bpf: verifier: add checks for BPF_ABS | BPF_IND instructions")
Signed-off-by: default avatarAlexei Starovoitov <ast@kernel.org>
Acked-by: default avatarDaniel Borkmann <daniel@iogearbox.net>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
Signed-off-by: default avatarKamal Mostafa <kamal@canonical.com>
parent 2d1cda5b
......@@ -1213,6 +1213,7 @@ static int check_ld_abs(struct verifier_env *env, struct bpf_insn *insn)
}
if (insn->dst_reg != BPF_REG_0 || insn->off != 0 ||
BPF_SIZE(insn->code) == BPF_DW ||
(mode == BPF_ABS && insn->src_reg != BPF_REG_0)) {
verbose("BPF_LD_ABS uses reserved fields\n");
return -EINVAL;
......
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