net: filter: add test for loading SKF_AD_OFF limits
This check tests that overloading BPF_LD | BPF_ABS with an
always invalid BPF extension, that is SKF_AD_MAX, fails to
make sure classic BPF behaviour is correct in filter checker.
Also, we add a test for loading at packet offset SKF_AD_OFF-1
which should pass the filter, but later on fail during runtime.
Signed-off-by: Daniel Borkmann <dborkman@redhat.com>
Acked-by: Alexei Starovoitov <ast@plumgrid.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/lib/test_bpf.c b/lib/test_bpf.c
index 2d0a0d1..f8d2b2a 100644
--- a/lib/test_bpf.c
+++ b/lib/test_bpf.c
@@ -1655,6 +1655,28 @@
{ },
{ { 0, 0x2a5a5e5 } },
},
+ {
+ "check: SKF_AD_MAX",
+ .u.insns = {
+ BPF_STMT(BPF_LD | BPF_W | BPF_ABS,
+ SKF_AD_OFF + SKF_AD_MAX),
+ BPF_STMT(BPF_RET | BPF_A, 0),
+ },
+ CLASSIC | FLAG_NO_DATA | FLAG_EXPECTED_FAIL,
+ { },
+ { },
+ },
+ { /* Passes checker but fails during runtime. */
+ "LD [SKF_AD_OFF-1]",
+ .u.insns = {
+ BPF_STMT(BPF_LD | BPF_W | BPF_ABS,
+ SKF_AD_OFF - 1),
+ BPF_STMT(BPF_RET | BPF_K, 1),
+ },
+ CLASSIC,
+ { },
+ { { 1, 0 } },
+ },
};
static struct net_device dev;