diff mbox

[net-next,2/2] net: filter: use block statements in tcpdump tests

Message ID 1401128255-6545-3-git-send-email-dborkman@redhat.com
State Accepted, archived
Delegated to: David Miller
Headers show

Commit Message

Daniel Borkmann May 26, 2014, 6:17 p.m. UTC 
This patch converts raw opcodes for tcpdump tests into
BPF_STMT()/BPF_JUMP() combinations, which brings it into
conformity with the rest of the patches and it also makes
life easier to grasp what's going on in these particular
test cases when they ever fail. Also arrange payload from
the jump+holes test in a way as we have with other packet
payloads in the test suite.

Signed-off-by: Daniel Borkmann <dborkman@redhat.com>
---
 lib/test_bpf.c | 143 ++++++++++++++++++++++++++++++---------------------------
 1 file changed, 75 insertions(+), 68 deletions(-)

Comments

Alexei Starovoitov May 27, 2014, 6:20 a.m. UTC | #1 
On Mon, May 26, 2014 at 11:17 AM, Daniel Borkmann <dborkman@redhat.com> wrote:
> This patch converts raw opcodes for tcpdump tests into
> BPF_STMT()/BPF_JUMP() combinations, which brings it into
> conformity with the rest of the patches and it also makes
> life easier to grasp what's going on in these particular
> test cases when they ever fail. Also arrange payload from
> the jump+holes test in a way as we have with other packet
> payloads in the test suite.
>
> Signed-off-by: Daniel Borkmann <dborkman@redhat.com>

Acked-by: Alexei Starovoitov <ast@plumgrid.com>

> ---
>  lib/test_bpf.c | 143 ++++++++++++++++++++++++++++++---------------------------
>  1 file changed, 75 insertions(+), 68 deletions(-)
>
> diff --git a/lib/test_bpf.c b/lib/test_bpf.c
> index 6be9119..3c4a1e3 100644
> --- a/lib/test_bpf.c
> +++ b/lib/test_bpf.c
> @@ -560,30 +560,30 @@ static struct bpf_test tests[] = {
>         {
>                 "tcpdump port 22",
>                 .u.insns = {
> -                       { 0x28,  0,  0, 0x0000000c },
> -                       { 0x15,  0,  8, 0x000086dd },
> -                       { 0x30,  0,  0, 0x00000014 },
> -                       { 0x15,  2,  0, 0x00000084 },
> -                       { 0x15,  1,  0, 0x00000006 },
> -                       { 0x15,  0, 17, 0x00000011 },
> -                       { 0x28,  0,  0, 0x00000036 },
> -                       { 0x15, 14,  0, 0x00000016 },
> -                       { 0x28,  0,  0, 0x00000038 },
> -                       { 0x15, 12, 13, 0x00000016 },
> -                       { 0x15,  0, 12, 0x00000800 },
> -                       { 0x30,  0,  0, 0x00000017 },
> -                       { 0x15,  2,  0, 0x00000084 },
> -                       { 0x15,  1,  0, 0x00000006 },
> -                       { 0x15,  0,  8, 0x00000011 },
> -                       { 0x28,  0,  0, 0x00000014 },
> -                       { 0x45,  6,  0, 0x00001fff },
> -                       { 0xb1,  0,  0, 0x0000000e },
> -                       { 0x48,  0,  0, 0x0000000e },
> -                       { 0x15,  2,  0, 0x00000016 },
> -                       { 0x48,  0,  0, 0x00000010 },
> -                       { 0x15,  0,  1, 0x00000016 },
> -                       { 0x06,  0,  0, 0x0000ffff },
> -                       { 0x06,  0,  0, 0x00000000 },
> +                       BPF_STMT(BPF_LD | BPF_H | BPF_ABS, 12),
> +                       BPF_JUMP(BPF_JMP | BPF_JEQ | BPF_K, 0x86dd, 0, 8), /* IPv6 */
> +                       BPF_STMT(BPF_LD | BPF_B | BPF_ABS, 20),
> +                       BPF_JUMP(BPF_JMP | BPF_JEQ | BPF_K, 0x84, 2, 0),
> +                       BPF_JUMP(BPF_JMP | BPF_JEQ | BPF_K, 0x6, 1, 0),
> +                       BPF_JUMP(BPF_JMP | BPF_JEQ | BPF_K, 0x11, 0, 17),
> +                       BPF_STMT(BPF_LD | BPF_H | BPF_ABS, 54),
> +                       BPF_JUMP(BPF_JMP | BPF_JEQ | BPF_K, 22, 14, 0),
> +                       BPF_STMT(BPF_LD | BPF_H | BPF_ABS, 56),
> +                       BPF_JUMP(BPF_JMP | BPF_JEQ | BPF_K, 22, 12, 13),
> +                       BPF_JUMP(BPF_JMP | BPF_JEQ | BPF_K, 0x0800, 0, 12), /* IPv4 */
> +                       BPF_STMT(BPF_LD | BPF_B | BPF_ABS, 23),
> +                       BPF_JUMP(BPF_JMP | BPF_JEQ | BPF_K, 0x84, 2, 0),
> +                       BPF_JUMP(BPF_JMP | BPF_JEQ | BPF_K, 0x6, 1, 0),
> +                       BPF_JUMP(BPF_JMP | BPF_JEQ | BPF_K, 0x11, 0, 8),
> +                       BPF_STMT(BPF_LD | BPF_H | BPF_ABS, 20),
> +                       BPF_JUMP(BPF_JMP | BPF_JSET | BPF_K, 0x1fff, 6, 0),
> +                       BPF_STMT(BPF_LDX | BPF_B | BPF_MSH, 14),
> +                       BPF_STMT(BPF_LD | BPF_H | BPF_IND, 14),
> +                       BPF_JUMP(BPF_JMP | BPF_JEQ | BPF_K, 22, 2, 0),
> +                       BPF_STMT(BPF_LD | BPF_H | BPF_IND, 16),
> +                       BPF_JUMP(BPF_JMP | BPF_JEQ | BPF_K, 22, 0, 1),
> +                       BPF_STMT(BPF_RET | BPF_K, 0xffff),
> +                       BPF_STMT(BPF_RET | BPF_K, 0),
>                 },
>                 CLASSIC,
>                 /* 3c:07:54:43:e5:76 > 10:bf:48:d6:43:d6, ethertype IPv4(0x0800)
> @@ -609,39 +609,39 @@ static struct bpf_test tests[] = {
>                          * ((ip[0]&0xf)<<2)) - ((tcp[12]&0xf0)>>2)) != 0) and
>                          * (len > 115 or len < 30000000000)' -d
>                          */
> -                       { 0x28,  0,  0, 0x0000000c },
> -                       { 0x15, 30,  0, 0x000086dd },
> -                       { 0x15,  0, 29, 0x00000800 },
> -                       { 0x30,  0,  0, 0x00000017 },
> -                       { 0x15,  0, 27, 0x00000006 },
> -                       { 0x28,  0,  0, 0x00000014 },
> -                       { 0x45, 25,  0, 0x00001fff },
> -                       { 0xb1,  0,  0, 0x0000000e },
> -                       { 0x48,  0,  0, 0x0000000e },
> -                       { 0x15,  2,  0, 0x00000016 },
> -                       { 0x48,  0,  0, 0x00000010 },
> -                       { 0x15,  0, 20, 0x00000016 },
> -                       { 0x28,  0,  0, 0x00000010 },
> -                       { 0x02,  0,  0, 0x00000001 },
> -                       { 0x30,  0,  0, 0x0000000e },
> -                       { 0x54,  0,  0, 0x0000000f },
> -                       { 0x64,  0,  0, 0x00000002 },
> -                       { 0x07,  0,  0, 0x00000005 },
> -                       { 0x60,  0,  0, 0x00000001 },
> -                       { 0x1c,  0,  0, 0x00000000 },
> -                       { 0x02,  0,  0, 0x00000005 },
> -                       { 0xb1,  0,  0, 0x0000000e },
> -                       { 0x50,  0,  0, 0x0000001a },
> -                       { 0x54,  0,  0, 0x000000f0 },
> -                       { 0x74,  0,  0, 0x00000002 },
> -                       { 0x07,  0,  0, 0x00000009 },
> -                       { 0x60,  0,  0, 0x00000005 },
> -                       { 0x1d,  4,  0, 0x00000000 },
> -                       { 0x80,  0,  0, 0x00000000 },
> -                       { 0x25,  1,  0, 0x00000073 },
> -                       { 0x35,  1,  0, 0xfc23ac00 },
> -                       { 0x06,  0,  0, 0x0000ffff },
> -                       { 0x06,  0,  0, 0x00000000 },
> +                       BPF_STMT(BPF_LD | BPF_H | BPF_ABS, 12),
> +                       BPF_JUMP(BPF_JMP | BPF_JEQ | BPF_K, 0x86dd, 30, 0),
> +                       BPF_JUMP(BPF_JMP | BPF_JEQ | BPF_K, 0x800, 0, 29),
> +                       BPF_STMT(BPF_LD | BPF_B | BPF_ABS, 23),
> +                       BPF_JUMP(BPF_JMP | BPF_JEQ | BPF_K, 0x6, 0, 27),
> +                       BPF_STMT(BPF_LD | BPF_H | BPF_ABS, 20),
> +                       BPF_JUMP(BPF_JMP | BPF_JSET | BPF_K, 0x1fff, 25, 0),
> +                       BPF_STMT(BPF_LDX | BPF_B | BPF_MSH, 14),
> +                       BPF_STMT(BPF_LD | BPF_H | BPF_IND, 14),
> +                       BPF_JUMP(BPF_JMP | BPF_JEQ | BPF_K, 22, 2, 0),
> +                       BPF_STMT(BPF_LD | BPF_H | BPF_IND, 16),
> +                       BPF_JUMP(BPF_JMP | BPF_JEQ | BPF_K, 22, 0, 20),
> +                       BPF_STMT(BPF_LD | BPF_H | BPF_ABS, 16),
> +                       BPF_STMT(BPF_ST, 1),
> +                       BPF_STMT(BPF_LD | BPF_B | BPF_ABS, 14),
> +                       BPF_STMT(BPF_ALU | BPF_AND | BPF_K, 0xf),
> +                       BPF_STMT(BPF_ALU | BPF_LSH | BPF_K, 2),
> +                       BPF_STMT(BPF_MISC | BPF_TAX, 0x5), /* libpcap emits K on TAX */

interesting observation. It means that libpcap doesn't init memory
properly and other fields just have junk in them?
and because it was doing it forever we need to accept such 'valid'
instructions? Oh well. ok.
Note to self: make sure to check for tidy instructions in eBPF verifier.

> +                       BPF_STMT(BPF_LD | BPF_MEM, 1),
> +                       BPF_STMT(BPF_ALU | BPF_SUB | BPF_X, 0),
> +                       BPF_STMT(BPF_ST, 5),
> +                       BPF_STMT(BPF_LDX | BPF_B | BPF_MSH, 14),
> +                       BPF_STMT(BPF_LD | BPF_B | BPF_IND, 26),
> +                       BPF_STMT(BPF_ALU | BPF_AND | BPF_K, 0xf0),
> +                       BPF_STMT(BPF_ALU | BPF_RSH | BPF_K, 2),
> +                       BPF_STMT(BPF_MISC | BPF_TAX, 0x9), /* libpcap emits K on TAX */
> +                       BPF_STMT(BPF_LD | BPF_MEM, 5),
> +                       BPF_JUMP(BPF_JMP | BPF_JEQ | BPF_X, 0, 4, 0),
> +                       BPF_STMT(BPF_LD | BPF_LEN, 0),
> +                       BPF_JUMP(BPF_JMP | BPF_JGT | BPF_K, 0x73, 1, 0),
> +                       BPF_JUMP(BPF_JMP | BPF_JGE | BPF_K, 0xfc23ac00, 1, 0),
> +                       BPF_STMT(BPF_RET | BPF_K, 0xffff),
> +                       BPF_STMT(BPF_RET | BPF_K, 0),
>                 },
>                 CLASSIC,
>                 { 0x10, 0xbf, 0x48, 0xd6, 0x43, 0xd6,
> @@ -1453,17 +1453,24 @@ static struct bpf_test tests[] = {
>                         BPF_STMT(BPF_RET | BPF_A, 0),
>                 },
>                 CLASSIC,
> -               { 0x00, 0x1b, 0x21, 0x3c, 0x9d, 0xf8, 0x90, 0xe2,
> -                 0xba, 0x0a, 0x56, 0xb4, 0x08, 0x00, 0x45, 0x00,
> -                 0x00, 0x28, 0x00, 0x00, 0x20, 0x00, 0x40, 0x11,
> -                 0x00, 0x00, 0xc0, 0xa8, 0x33, 0x01, 0xc0, 0xa8,
> -                 0x33, 0x02, 0xbb, 0xb6, 0xa9, 0xfa, 0x00, 0x14,
> -                 0x00, 0x00, 0xcc, 0xcc, 0xcc, 0xcc, 0xcc, 0xcc,
> -                 0xcc, 0xcc, 0xcc, 0xcc, 0xcc, 0xcc, 0xcc, 0xcc,
> -                 0xcc, 0xcc, 0xcc, 0xcc, 0xcc, 0xcc, 0xcc, 0xcc,
> -                 0xcc, 0xcc, 0xcc, 0xcc, 0xcc, 0xcc, 0xcc, 0xcc,
> -                 0xcc, 0xcc, 0xcc, 0xcc, 0xcc, 0xcc, 0xcc, 0xcc,
> -                 0xcc, 0xcc, 0xcc, 0xcc, 0xcc, 0xcc, 0xcc, 0xcc },
> +               { 0x00, 0x1b, 0x21, 0x3c, 0x9d, 0xf8,
> +                 0x90, 0xe2, 0xba, 0x0a, 0x56, 0xb4,
> +                 0x08, 0x00,
> +                 0x45, 0x00, 0x00, 0x28, 0x00, 0x00,
> +                 0x20, 0x00, 0x40, 0x11, 0x00, 0x00, /* IP header */
> +                 0xc0, 0xa8, 0x33, 0x01,
> +                 0xc0, 0xa8, 0x33, 0x02,
> +                 0xbb, 0xb6,
> +                 0xa9, 0xfa,
> +                 0x00, 0x14, 0x00, 0x00,
> +                 0xcc, 0xcc, 0xcc, 0xcc, 0xcc, 0xcc,
> +                 0xcc, 0xcc, 0xcc, 0xcc, 0xcc, 0xcc,
> +                 0xcc, 0xcc, 0xcc, 0xcc, 0xcc, 0xcc,
> +                 0xcc, 0xcc, 0xcc, 0xcc, 0xcc, 0xcc,
> +                 0xcc, 0xcc, 0xcc, 0xcc, 0xcc, 0xcc,
> +                 0xcc, 0xcc, 0xcc, 0xcc, 0xcc, 0xcc,
> +                 0xcc, 0xcc, 0xcc, 0xcc, 0xcc, 0xcc,
> +                 0xcc, 0xcc, 0xcc, 0xcc },
>                 { { 88, 0x001b } }
>         },
>         {
> --
> 1.7.11.7
>
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Daniel Borkmann May 27, 2014, 5 p.m. UTC | #2 
On 05/27/2014 08:20 AM, Alexei Starovoitov wrote:
...
>> +                       BPF_STMT(BPF_ALU | BPF_LSH | BPF_K, 2),
>> +                       BPF_STMT(BPF_MISC | BPF_TAX, 0x5), /* libpcap emits K on TAX */
>
> interesting observation. It means that libpcap doesn't init memory
> properly and other fields just have junk in them?
> and because it was doing it forever we need to accept such 'valid'
> instructions? Oh well. ok.

Hmm, doesn't look like totally random. Perhaps they're
storing some intermediate value in it or something, and
don't clear that out as we have accepted that since ever,
but that shouldn't do anything anyway here. ;)
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diff mbox

Patch

diff --git a/lib/test_bpf.c b/lib/test_bpf.c
index 6be9119..3c4a1e3 100644
--- a/lib/test_bpf.c
+++ b/lib/test_bpf.c
@@ -560,30 +560,30 @@  static struct bpf_test tests[] = {
 	{
 		"tcpdump port 22",
 		.u.insns = {
-			{ 0x28,  0,  0, 0x0000000c },
-			{ 0x15,  0,  8, 0x000086dd },
-			{ 0x30,  0,  0, 0x00000014 },
-			{ 0x15,  2,  0, 0x00000084 },
-			{ 0x15,  1,  0, 0x00000006 },
-			{ 0x15,  0, 17, 0x00000011 },
-			{ 0x28,  0,  0, 0x00000036 },
-			{ 0x15, 14,  0, 0x00000016 },
-			{ 0x28,  0,  0, 0x00000038 },
-			{ 0x15, 12, 13, 0x00000016 },
-			{ 0x15,  0, 12, 0x00000800 },
-			{ 0x30,  0,  0, 0x00000017 },
-			{ 0x15,  2,  0, 0x00000084 },
-			{ 0x15,  1,  0, 0x00000006 },
-			{ 0x15,  0,  8, 0x00000011 },
-			{ 0x28,  0,  0, 0x00000014 },
-			{ 0x45,  6,  0, 0x00001fff },
-			{ 0xb1,  0,  0, 0x0000000e },
-			{ 0x48,  0,  0, 0x0000000e },
-			{ 0x15,  2,  0, 0x00000016 },
-			{ 0x48,  0,  0, 0x00000010 },
-			{ 0x15,  0,  1, 0x00000016 },
-			{ 0x06,  0,  0, 0x0000ffff },
-			{ 0x06,  0,  0, 0x00000000 },
+			BPF_STMT(BPF_LD | BPF_H | BPF_ABS, 12),
+			BPF_JUMP(BPF_JMP | BPF_JEQ | BPF_K, 0x86dd, 0, 8), /* IPv6 */
+			BPF_STMT(BPF_LD | BPF_B | BPF_ABS, 20),
+			BPF_JUMP(BPF_JMP | BPF_JEQ | BPF_K, 0x84, 2, 0),
+			BPF_JUMP(BPF_JMP | BPF_JEQ | BPF_K, 0x6, 1, 0),
+			BPF_JUMP(BPF_JMP | BPF_JEQ | BPF_K, 0x11, 0, 17),
+			BPF_STMT(BPF_LD | BPF_H | BPF_ABS, 54),
+			BPF_JUMP(BPF_JMP | BPF_JEQ | BPF_K, 22, 14, 0),
+			BPF_STMT(BPF_LD | BPF_H | BPF_ABS, 56),
+			BPF_JUMP(BPF_JMP | BPF_JEQ | BPF_K, 22, 12, 13),
+			BPF_JUMP(BPF_JMP | BPF_JEQ | BPF_K, 0x0800, 0, 12), /* IPv4 */
+			BPF_STMT(BPF_LD | BPF_B | BPF_ABS, 23),
+			BPF_JUMP(BPF_JMP | BPF_JEQ | BPF_K, 0x84, 2, 0),
+			BPF_JUMP(BPF_JMP | BPF_JEQ | BPF_K, 0x6, 1, 0),
+			BPF_JUMP(BPF_JMP | BPF_JEQ | BPF_K, 0x11, 0, 8),
+			BPF_STMT(BPF_LD | BPF_H | BPF_ABS, 20),
+			BPF_JUMP(BPF_JMP | BPF_JSET | BPF_K, 0x1fff, 6, 0),
+			BPF_STMT(BPF_LDX | BPF_B | BPF_MSH, 14),
+			BPF_STMT(BPF_LD | BPF_H | BPF_IND, 14),
+			BPF_JUMP(BPF_JMP | BPF_JEQ | BPF_K, 22, 2, 0),
+			BPF_STMT(BPF_LD | BPF_H | BPF_IND, 16),
+			BPF_JUMP(BPF_JMP | BPF_JEQ | BPF_K, 22, 0, 1),
+			BPF_STMT(BPF_RET | BPF_K, 0xffff),
+			BPF_STMT(BPF_RET | BPF_K, 0),
 		},
 		CLASSIC,
 		/* 3c:07:54:43:e5:76 > 10:bf:48:d6:43:d6, ethertype IPv4(0x0800)
@@ -609,39 +609,39 @@  static struct bpf_test tests[] = {
 			 * ((ip[0]&0xf)<<2)) - ((tcp[12]&0xf0)>>2)) != 0) and
 			 * (len > 115 or len < 30000000000)' -d
 			 */
-			{ 0x28,  0,  0, 0x0000000c },
-			{ 0x15, 30,  0, 0x000086dd },
-			{ 0x15,  0, 29, 0x00000800 },
-			{ 0x30,  0,  0, 0x00000017 },
-			{ 0x15,  0, 27, 0x00000006 },
-			{ 0x28,  0,  0, 0x00000014 },
-			{ 0x45, 25,  0, 0x00001fff },
-			{ 0xb1,  0,  0, 0x0000000e },
-			{ 0x48,  0,  0, 0x0000000e },
-			{ 0x15,  2,  0, 0x00000016 },
-			{ 0x48,  0,  0, 0x00000010 },
-			{ 0x15,  0, 20, 0x00000016 },
-			{ 0x28,  0,  0, 0x00000010 },
-			{ 0x02,  0,  0, 0x00000001 },
-			{ 0x30,  0,  0, 0x0000000e },
-			{ 0x54,  0,  0, 0x0000000f },
-			{ 0x64,  0,  0, 0x00000002 },
-			{ 0x07,  0,  0, 0x00000005 },
-			{ 0x60,  0,  0, 0x00000001 },
-			{ 0x1c,  0,  0, 0x00000000 },
-			{ 0x02,  0,  0, 0x00000005 },
-			{ 0xb1,  0,  0, 0x0000000e },
-			{ 0x50,  0,  0, 0x0000001a },
-			{ 0x54,  0,  0, 0x000000f0 },
-			{ 0x74,  0,  0, 0x00000002 },
-			{ 0x07,  0,  0, 0x00000009 },
-			{ 0x60,  0,  0, 0x00000005 },
-			{ 0x1d,  4,  0, 0x00000000 },
-			{ 0x80,  0,  0, 0x00000000 },
-			{ 0x25,  1,  0, 0x00000073 },
-			{ 0x35,  1,  0, 0xfc23ac00 },
-			{ 0x06,  0,  0, 0x0000ffff },
-			{ 0x06,  0,  0, 0x00000000 },
+			BPF_STMT(BPF_LD | BPF_H | BPF_ABS, 12),
+			BPF_JUMP(BPF_JMP | BPF_JEQ | BPF_K, 0x86dd, 30, 0),
+			BPF_JUMP(BPF_JMP | BPF_JEQ | BPF_K, 0x800, 0, 29),
+			BPF_STMT(BPF_LD | BPF_B | BPF_ABS, 23),
+			BPF_JUMP(BPF_JMP | BPF_JEQ | BPF_K, 0x6, 0, 27),
+			BPF_STMT(BPF_LD | BPF_H | BPF_ABS, 20),
+			BPF_JUMP(BPF_JMP | BPF_JSET | BPF_K, 0x1fff, 25, 0),
+			BPF_STMT(BPF_LDX | BPF_B | BPF_MSH, 14),
+			BPF_STMT(BPF_LD | BPF_H | BPF_IND, 14),
+			BPF_JUMP(BPF_JMP | BPF_JEQ | BPF_K, 22, 2, 0),
+			BPF_STMT(BPF_LD | BPF_H | BPF_IND, 16),
+			BPF_JUMP(BPF_JMP | BPF_JEQ | BPF_K, 22, 0, 20),
+			BPF_STMT(BPF_LD | BPF_H | BPF_ABS, 16),
+			BPF_STMT(BPF_ST, 1),
+			BPF_STMT(BPF_LD | BPF_B | BPF_ABS, 14),
+			BPF_STMT(BPF_ALU | BPF_AND | BPF_K, 0xf),
+			BPF_STMT(BPF_ALU | BPF_LSH | BPF_K, 2),
+			BPF_STMT(BPF_MISC | BPF_TAX, 0x5), /* libpcap emits K on TAX */
+			BPF_STMT(BPF_LD | BPF_MEM, 1),
+			BPF_STMT(BPF_ALU | BPF_SUB | BPF_X, 0),
+			BPF_STMT(BPF_ST, 5),
+			BPF_STMT(BPF_LDX | BPF_B | BPF_MSH, 14),
+			BPF_STMT(BPF_LD | BPF_B | BPF_IND, 26),
+			BPF_STMT(BPF_ALU | BPF_AND | BPF_K, 0xf0),
+			BPF_STMT(BPF_ALU | BPF_RSH | BPF_K, 2),
+			BPF_STMT(BPF_MISC | BPF_TAX, 0x9), /* libpcap emits K on TAX */
+			BPF_STMT(BPF_LD | BPF_MEM, 5),
+			BPF_JUMP(BPF_JMP | BPF_JEQ | BPF_X, 0, 4, 0),
+			BPF_STMT(BPF_LD | BPF_LEN, 0),
+			BPF_JUMP(BPF_JMP | BPF_JGT | BPF_K, 0x73, 1, 0),
+			BPF_JUMP(BPF_JMP | BPF_JGE | BPF_K, 0xfc23ac00, 1, 0),
+			BPF_STMT(BPF_RET | BPF_K, 0xffff),
+			BPF_STMT(BPF_RET | BPF_K, 0),
 		},
 		CLASSIC,
 		{ 0x10, 0xbf, 0x48, 0xd6, 0x43, 0xd6,
@@ -1453,17 +1453,24 @@  static struct bpf_test tests[] = {
 			BPF_STMT(BPF_RET | BPF_A, 0),
 		},
 		CLASSIC,
-		{ 0x00, 0x1b, 0x21, 0x3c, 0x9d, 0xf8, 0x90, 0xe2,
-		  0xba, 0x0a, 0x56, 0xb4, 0x08, 0x00, 0x45, 0x00,
-		  0x00, 0x28, 0x00, 0x00, 0x20, 0x00, 0x40, 0x11,
-		  0x00, 0x00, 0xc0, 0xa8, 0x33, 0x01, 0xc0, 0xa8,
-		  0x33, 0x02, 0xbb, 0xb6, 0xa9, 0xfa, 0x00, 0x14,
-		  0x00, 0x00, 0xcc, 0xcc, 0xcc, 0xcc, 0xcc, 0xcc,
-		  0xcc, 0xcc, 0xcc, 0xcc, 0xcc, 0xcc, 0xcc, 0xcc,
-		  0xcc, 0xcc, 0xcc, 0xcc, 0xcc, 0xcc, 0xcc, 0xcc,
-		  0xcc, 0xcc, 0xcc, 0xcc, 0xcc, 0xcc, 0xcc, 0xcc,
-		  0xcc, 0xcc, 0xcc, 0xcc, 0xcc, 0xcc, 0xcc, 0xcc,
-		  0xcc, 0xcc, 0xcc, 0xcc, 0xcc, 0xcc, 0xcc, 0xcc },
+		{ 0x00, 0x1b, 0x21, 0x3c, 0x9d, 0xf8,
+		  0x90, 0xe2, 0xba, 0x0a, 0x56, 0xb4,
+		  0x08, 0x00,
+		  0x45, 0x00, 0x00, 0x28, 0x00, 0x00,
+		  0x20, 0x00, 0x40, 0x11, 0x00, 0x00, /* IP header */
+		  0xc0, 0xa8, 0x33, 0x01,
+		  0xc0, 0xa8, 0x33, 0x02,
+		  0xbb, 0xb6,
+		  0xa9, 0xfa,
+		  0x00, 0x14, 0x00, 0x00,
+		  0xcc, 0xcc, 0xcc, 0xcc, 0xcc, 0xcc,
+		  0xcc, 0xcc, 0xcc, 0xcc, 0xcc, 0xcc,
+		  0xcc, 0xcc, 0xcc, 0xcc, 0xcc, 0xcc,
+		  0xcc, 0xcc, 0xcc, 0xcc, 0xcc, 0xcc,
+		  0xcc, 0xcc, 0xcc, 0xcc, 0xcc, 0xcc,
+		  0xcc, 0xcc, 0xcc, 0xcc, 0xcc, 0xcc,
+		  0xcc, 0xcc, 0xcc, 0xcc, 0xcc, 0xcc,
+		  0xcc, 0xcc, 0xcc, 0xcc },
 		{ { 88, 0x001b } }
 	},
 	{