[PATCH 4.4 05/46] bpf/verifier: reject BPF_ALU64|BPF_END

[Greg Kroah-Hartman]

4.4-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Edward Cree <ec...@solarflare.com>


[ Upstream commit e67b8a685c7c984e834e3181ef4619cd7025a136 ]

Neither ___bpf_prog_run nor the JITs accept it.
Also adds a new test case.

Fixes: 17a5267067f3 ("bpf: verifier (add verifier core)")
Signed-off-by: Edward Cree <ec...@solarflare.com>
Acked-by: Alexei Starovoitov <a...@kernel.org>
Acked-by: Daniel Borkmann <dan...@iogearbox.net>
Signed-off-by: David S. Miller <da...@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gre...@linuxfoundation.org>
---
 kernel/bpf/verifier.c |    3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

--- a/kernel/bpf/verifier.c
+++ b/kernel/bpf/verifier.c
@@ -1033,7 +1033,8 @@ static int check_alu_op(struct verifier_
                        }
                } else {
                        if (insn->src_reg != BPF_REG_0 || insn->off != 0 ||
-                           (insn->imm != 16 && insn->imm != 32 && insn->imm != 
64)) {
+                           (insn->imm != 16 && insn->imm != 32 && insn->imm != 
64) ||
+                           BPF_CLASS(insn->code) == BPF_ALU64) {
                                verbose("BPF_END uses reserved fields\n");
                                return -EINVAL;
                        }