Merge git://git.kernel.org/pub/scm/linux/kernel/git/bpf/bpf

Daniel Borkmann says:

====================
pull-request: bpf 2017-12-17

The following pull-request contains BPF updates for your *net* tree.

The main changes are:

1) Fix a corner case in generic XDP where we have non-linear skbs
   but enough tailroom in the skb to not miss to linearizing there,
   from Song.

2) Fix BPF JIT bugs in s390x and ppc64 to not recache skb data when
   BPF context is not skb, from Daniel.

3) Fix a BPF JIT bug in sparc64 where recaching skb data after helper
   call would use the wrong register for the skb, from Daniel.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 43 insertions, 0 deletions

diff --git a/lib/test_bpf.c b/lib/test_bpf.c
index aa8812ae6776..9e9748089270 100644
--- a/lib/test_bpf.c
+++ b/lib/test_bpf.c
@@ -435,6 +435,41 @@ loop:
 	return 0;
 }
 
+static int bpf_fill_ld_abs_vlan_push_pop2(struct bpf_test *self)
+{
+	struct bpf_insn *insn;
+
+	insn = kmalloc_array(16, sizeof(*insn), GFP_KERNEL);
+	if (!insn)
+		return -ENOMEM;
+
+	/* Due to func address being non-const, we need to
+	 * assemble this here.
+	 */
+	insn[0] = BPF_MOV64_REG(R6, R1);
+	insn[1] = BPF_LD_ABS(BPF_B, 0);
+	insn[2] = BPF_LD_ABS(BPF_H, 0);
+	insn[3] = BPF_LD_ABS(BPF_W, 0);
+	insn[4] = BPF_MOV64_REG(R7, R6);
+	insn[5] = BPF_MOV64_IMM(R6, 0);
+	insn[6] = BPF_MOV64_REG(R1, R7);
+	insn[7] = BPF_MOV64_IMM(R2, 1);
+	insn[8] = BPF_MOV64_IMM(R3, 2);
+	insn[9] = BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0,
+			       bpf_skb_vlan_push_proto.func - __bpf_call_base);
+	insn[10] = BPF_MOV64_REG(R6, R7);
+	insn[11] = BPF_LD_ABS(BPF_B, 0);
+	insn[12] = BPF_LD_ABS(BPF_H, 0);
+	insn[13] = BPF_LD_ABS(BPF_W, 0);
+	insn[14] = BPF_MOV64_IMM(R0, 42);
+	insn[15] = BPF_EXIT_INSN();
+
+	self->u.ptr.insns = insn;
+	self->u.ptr.len = 16;
+
+	return 0;
+}
+
 static int bpf_fill_jump_around_ld_abs(struct bpf_test *self)
 {
 	unsigned int len = BPF_MAXINSNS;
@@ -6066,6 +6101,14 @@ static struct bpf_test tests[] = {
 		{},
 		{ {0x1, 0x42 } },
 	},
+	{
+		"LD_ABS with helper changing skb data",
+		{ },
+		INTERNAL,
+		{ 0x34 },
+		{ { ETH_HLEN, 42 } },
+		.fill_helper = bpf_fill_ld_abs_vlan_push_pop2,
+	},
 };
 
 static struct net_device dev;