Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]

Groups > linux.kernel > #1401884 > unrolled thread

[PATCH 4.5 006/101] bpf/verifier: reject invalid LD_ABS | BPF_DW instruction

Back to article view | Back to linux.kernel

This discussion starts older than the indexed window; earlier articles aren't shown. The article labeled Started by below is the oldest one visible, not the original post.

Contents

  [PATCH 4.5 006/101] bpf/verifier: reject invalid LD_ABS | BPF_DW instruction Greg Kroah-Hartman <gregkh@linuxfoundation.org> - 2016-05-17 03:30 +0200

#1401884 — [PATCH 4.5 006/101] bpf/verifier: reject invalid LD_ABS | BPF_DW instruction

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

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

From: Alexei Starovoitov <ast@fb.com>

[ Upstream commit d82bccc69041a51f7b7b9b4a36db0772f4cdba21 ]

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: ddd872bc3098 ("bpf: verifier: add checks for BPF_ABS | BPF_IND instructions")
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Acked-by: Daniel Borkmann <daniel@iogearbox.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 kernel/bpf/verifier.c |    1 +
 1 file changed, 1 insertion(+)

--- a/kernel/bpf/verifier.c
+++ b/kernel/bpf/verifier.c
@@ -1348,6 +1348,7 @@ static int check_ld_abs(struct verifier_
 	}
 
 	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;

[toc] | [standalone]

Back to top | Article view | linux.kernel

csiph-web