Hi all,

Today's linux-next merge of the net-next tree got a conflict in:

  tools/testing/selftests/bpf/test_verifier.c

between commit:

  28e33f9d78eef ("bpf: disallow arithmetic operations on context pointer")

from the net tree and commit:

  22c8852624fc9 ("bpf: improve selftests and add tests for meta pointer")

from the net-next tree.

I fixed it up (see below) and can carry the fix as necessary. This
is now fixed as far as linux-next is concerned, but any non trivial
conflicts should be mentioned to your upstream maintainer when your tree
is submitted for merging.  You may also want to consider cooperating
with the maintainer of the conflicting tree to minimise any particularly
complex conflicts.

diff --cc tools/testing/selftests/bpf/test_verifier.c
index 3c7d3a45a3c5,cc91d0159f43..000000000000
--- a/tools/testing/selftests/bpf/test_verifier.c
+++ b/tools/testing/selftests/bpf/test_verifier.c
@@@ -6645,20 -6645,325 +6645,339 @@@ static struct bpf_test tests[] = 
  		.errstr = "BPF_END uses reserved fields",
  		.result = REJECT,
  	},
 +	{
 +		"arithmetic ops make PTR_TO_CTX unusable",
 +		.insns = {
 +			BPF_ALU64_IMM(BPF_ADD, BPF_REG_1,
 +				      offsetof(struct __sk_buff, data) -
 +				      offsetof(struct __sk_buff, mark)),
 +			BPF_LDX_MEM(BPF_W, BPF_REG_0, BPF_REG_1,
 +				    offsetof(struct __sk_buff, mark)),
 +			BPF_EXIT_INSN(),
 +		},
 +		.errstr = "dereference of modified ctx ptr R1 off=68+8, ctx+const is allowed, ctx+const+const is not",
 +		.result = REJECT,
 +		.prog_type = BPF_PROG_TYPE_SCHED_CLS,
 +	},
+ 	{
+ 		"meta access, test1",
+ 		.insns = {
+ 			BPF_LDX_MEM(BPF_W, BPF_REG_2, BPF_REG_1,
+ 				    offsetof(struct xdp_md, data_meta)),
+ 			BPF_LDX_MEM(BPF_W, BPF_REG_3, BPF_REG_1,
+ 				    offsetof(struct xdp_md, data)),
+ 			BPF_MOV64_REG(BPF_REG_0, BPF_REG_2),
+ 			BPF_ALU64_IMM(BPF_ADD, BPF_REG_0, 8),
+ 			BPF_JMP_REG(BPF_JGT, BPF_REG_0, BPF_REG_3, 1),
+ 			BPF_LDX_MEM(BPF_B, BPF_REG_0, BPF_REG_2, 0),
+ 			BPF_MOV64_IMM(BPF_REG_0, 0),
+ 			BPF_EXIT_INSN(),
+ 		},
+ 		.result = ACCEPT,
+ 		.prog_type = BPF_PROG_TYPE_XDP,
+ 	},
+ 	{
+ 		"meta access, test2",
+ 		.insns = {
+ 			BPF_LDX_MEM(BPF_W, BPF_REG_2, BPF_REG_1,
+ 				    offsetof(struct xdp_md, data_meta)),
+ 			BPF_LDX_MEM(BPF_W, BPF_REG_3, BPF_REG_1,
+ 				    offsetof(struct xdp_md, data)),
+ 			BPF_MOV64_REG(BPF_REG_0, BPF_REG_2),
+ 			BPF_ALU64_IMM(BPF_SUB, BPF_REG_0, 8),
+ 			BPF_MOV64_REG(BPF_REG_4, BPF_REG_2),
+ 			BPF_ALU64_IMM(BPF_ADD, BPF_REG_4, 8),
+ 			BPF_JMP_REG(BPF_JGT, BPF_REG_4, BPF_REG_3, 1),
+ 			BPF_LDX_MEM(BPF_B, BPF_REG_0, BPF_REG_0, 0),
+ 			BPF_MOV64_IMM(BPF_REG_0, 0),
+ 			BPF_EXIT_INSN(),
+ 		},
+ 		.result = REJECT,
+ 		.errstr = "invalid access to packet, off=-8",
+ 		.prog_type = BPF_PROG_TYPE_XDP,
+ 	},
+ 	{
+ 		"meta access, test3",
+ 		.insns = {
+ 			BPF_LDX_MEM(BPF_W, BPF_REG_2, BPF_REG_1,
+ 				    offsetof(struct xdp_md, data_meta)),
+ 			BPF_LDX_MEM(BPF_W, BPF_REG_3, BPF_REG_1,
+ 				    offsetof(struct xdp_md, data_end)),
+ 			BPF_MOV64_REG(BPF_REG_0, BPF_REG_2),
+ 			BPF_ALU64_IMM(BPF_ADD, BPF_REG_0, 8),
+ 			BPF_JMP_REG(BPF_JGT, BPF_REG_0, BPF_REG_3, 1),
+ 			BPF_LDX_MEM(BPF_B, BPF_REG_0, BPF_REG_2, 0),
+ 			BPF_MOV64_IMM(BPF_REG_0, 0),
+ 			BPF_EXIT_INSN(),
+ 		},
+ 		.result = REJECT,
+ 		.errstr = "invalid access to packet",
+ 		.prog_type = BPF_PROG_TYPE_XDP,
+ 	},
+ 	{
+ 		"meta access, test4",
+ 		.insns = {
+ 			BPF_LDX_MEM(BPF_W, BPF_REG_2, BPF_REG_1,
+ 				    offsetof(struct xdp_md, data_meta)),
+ 			BPF_LDX_MEM(BPF_W, BPF_REG_3, BPF_REG_1,
+ 				    offsetof(struct xdp_md, data_end)),
+ 			BPF_LDX_MEM(BPF_W, BPF_REG_4, BPF_REG_1,
+ 				    offsetof(struct xdp_md, data)),
+ 			BPF_MOV64_REG(BPF_REG_0, BPF_REG_4),
+ 			BPF_ALU64_IMM(BPF_ADD, BPF_REG_0, 8),
+ 			BPF_JMP_REG(BPF_JGT, BPF_REG_0, BPF_REG_3, 1),
+ 			BPF_LDX_MEM(BPF_B, BPF_REG_0, BPF_REG_2, 0),
+ 			BPF_MOV64_IMM(BPF_REG_0, 0),
+ 			BPF_EXIT_INSN(),
+ 		},
+ 		.result = REJECT,
+ 		.errstr = "invalid access to packet",
+ 		.prog_type = BPF_PROG_TYPE_XDP,
+ 	},
+ 	{
+ 		"meta access, test5",
+ 		.insns = {
+ 			BPF_LDX_MEM(BPF_W, BPF_REG_3, BPF_REG_1,
+ 				    offsetof(struct xdp_md, data_meta)),
+ 			BPF_LDX_MEM(BPF_W, BPF_REG_4, BPF_REG_1,
+ 				    offsetof(struct xdp_md, data)),
+ 			BPF_MOV64_REG(BPF_REG_0, BPF_REG_3),
+ 			BPF_ALU64_IMM(BPF_ADD, BPF_REG_0, 8),
+ 			BPF_JMP_REG(BPF_JGT, BPF_REG_0, BPF_REG_4, 3),
+ 			BPF_MOV64_IMM(BPF_REG_2, -8),
+ 			BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0,
+ 				     BPF_FUNC_xdp_adjust_meta),
+ 			BPF_LDX_MEM(BPF_B, BPF_REG_0, BPF_REG_3, 0),
+ 			BPF_MOV64_IMM(BPF_REG_0, 0),
+ 			BPF_EXIT_INSN(),
+ 		},
+ 		.result = REJECT,
+ 		.errstr = "R3 !read_ok",
+ 		.prog_type = BPF_PROG_TYPE_XDP,
+ 	},
+ 	{
+ 		"meta access, test6",
+ 		.insns = {
+ 			BPF_LDX_MEM(BPF_W, BPF_REG_2, BPF_REG_1,
+ 				    offsetof(struct xdp_md, data_meta)),
+ 			BPF_LDX_MEM(BPF_W, BPF_REG_3, BPF_REG_1,
+ 				    offsetof(struct xdp_md, data)),
+ 			BPF_MOV64_REG(BPF_REG_0, BPF_REG_3),
+ 			BPF_ALU64_IMM(BPF_ADD, BPF_REG_0, 8),
+ 			BPF_MOV64_REG(BPF_REG_4, BPF_REG_2),
+ 			BPF_ALU64_IMM(BPF_ADD, BPF_REG_4, 8),
+ 			BPF_JMP_REG(BPF_JGT, BPF_REG_4, BPF_REG_0, 1),
+ 			BPF_LDX_MEM(BPF_B, BPF_REG_0, BPF_REG_2, 0),
+ 			BPF_MOV64_IMM(BPF_REG_0, 0),
+ 			BPF_EXIT_INSN(),
+ 		},
+ 		.result = REJECT,
+ 		.errstr = "invalid access to packet",
+ 		.prog_type = BPF_PROG_TYPE_XDP,
+ 	},
+ 	{
+ 		"meta access, test7",
+ 		.insns = {
+ 			BPF_LDX_MEM(BPF_W, BPF_REG_2, BPF_REG_1,
+ 				    offsetof(struct xdp_md, data_meta)),
+ 			BPF_LDX_MEM(BPF_W, BPF_REG_3, BPF_REG_1,
+ 				    offsetof(struct xdp_md, data)),
+ 			BPF_MOV64_REG(BPF_REG_0, BPF_REG_3),
+ 			BPF_ALU64_IMM(BPF_ADD, BPF_REG_0, 8),
+ 			BPF_MOV64_REG(BPF_REG_4, BPF_REG_2),
+ 			BPF_ALU64_IMM(BPF_ADD, BPF_REG_4, 8),
+ 			BPF_JMP_REG(BPF_JGT, BPF_REG_4, BPF_REG_3, 1),
+ 			BPF_LDX_MEM(BPF_B, BPF_REG_0, BPF_REG_2, 0),
+ 			BPF_MOV64_IMM(BPF_REG_0, 0),
+ 			BPF_EXIT_INSN(),
+ 		},
+ 		.result = ACCEPT,
+ 		.prog_type = BPF_PROG_TYPE_XDP,
+ 	},
+ 	{
+ 		"meta access, test8",
+ 		.insns = {
+ 			BPF_LDX_MEM(BPF_W, BPF_REG_2, BPF_REG_1,
+ 				    offsetof(struct xdp_md, data_meta)),
+ 			BPF_LDX_MEM(BPF_W, BPF_REG_3, BPF_REG_1,
+ 				    offsetof(struct xdp_md, data)),
+ 			BPF_MOV64_REG(BPF_REG_4, BPF_REG_2),
+ 			BPF_ALU64_IMM(BPF_ADD, BPF_REG_4, 0xFFFF),
+ 			BPF_JMP_REG(BPF_JGT, BPF_REG_4, BPF_REG_3, 1),
+ 			BPF_LDX_MEM(BPF_B, BPF_REG_0, BPF_REG_2, 0),
+ 			BPF_MOV64_IMM(BPF_REG_0, 0),
+ 			BPF_EXIT_INSN(),
+ 		},
+ 		.result = ACCEPT,
+ 		.prog_type = BPF_PROG_TYPE_XDP,
+ 	},
+ 	{
+ 		"meta access, test9",
+ 		.insns = {
+ 			BPF_LDX_MEM(BPF_W, BPF_REG_2, BPF_REG_1,
+ 				    offsetof(struct xdp_md, data_meta)),
+ 			BPF_LDX_MEM(BPF_W, BPF_REG_3, BPF_REG_1,
+ 				    offsetof(struct xdp_md, data)),
+ 			BPF_MOV64_REG(BPF_REG_4, BPF_REG_2),
+ 			BPF_ALU64_IMM(BPF_ADD, BPF_REG_4, 0xFFFF),
+ 			BPF_ALU64_IMM(BPF_ADD, BPF_REG_4, 1),
+ 			BPF_JMP_REG(BPF_JGT, BPF_REG_4, BPF_REG_3, 1),
+ 			BPF_LDX_MEM(BPF_B, BPF_REG_0, BPF_REG_2, 0),
+ 			BPF_MOV64_IMM(BPF_REG_0, 0),
+ 			BPF_EXIT_INSN(),
+ 		},
+ 		.result = REJECT,
+ 		.errstr = "invalid access to packet",
+ 		.prog_type = BPF_PROG_TYPE_XDP,
+ 	},
+ 	{
+ 		"meta access, test10",
+ 		.insns = {
+ 			BPF_LDX_MEM(BPF_W, BPF_REG_2, BPF_REG_1,
+ 				    offsetof(struct xdp_md, data_meta)),
+ 			BPF_LDX_MEM(BPF_W, BPF_REG_3, BPF_REG_1,
+ 				    offsetof(struct xdp_md, data)),
+ 			BPF_LDX_MEM(BPF_W, BPF_REG_4, BPF_REG_1,
+ 				    offsetof(struct xdp_md, data_end)),
+ 			BPF_MOV64_IMM(BPF_REG_5, 42),
+ 			BPF_MOV64_IMM(BPF_REG_6, 24),
+ 			BPF_STX_MEM(BPF_DW, BPF_REG_10, BPF_REG_5, -8),
+ 			BPF_STX_XADD(BPF_DW, BPF_REG_10, BPF_REG_6, -8),
+ 			BPF_LDX_MEM(BPF_DW, BPF_REG_5, BPF_REG_10, -8),
+ 			BPF_JMP_IMM(BPF_JGT, BPF_REG_5, 100, 6),
+ 			BPF_ALU64_REG(BPF_ADD, BPF_REG_3, BPF_REG_5),
+ 			BPF_MOV64_REG(BPF_REG_5, BPF_REG_3),
+ 			BPF_MOV64_REG(BPF_REG_6, BPF_REG_2),
+ 			BPF_ALU64_IMM(BPF_ADD, BPF_REG_6, 8),
+ 			BPF_JMP_REG(BPF_JGT, BPF_REG_6, BPF_REG_5, 1),
+ 			BPF_LDX_MEM(BPF_B, BPF_REG_2, BPF_REG_2, 0),
+ 			BPF_MOV64_IMM(BPF_REG_0, 0),
+ 			BPF_EXIT_INSN(),
+ 		},
+ 		.result = REJECT,
+ 		.errstr = "invalid access to packet",
+ 		.prog_type = BPF_PROG_TYPE_XDP,
+ 	},
+ 	{
+ 		"meta access, test11",
+ 		.insns = {
+ 			BPF_LDX_MEM(BPF_W, BPF_REG_2, BPF_REG_1,
+ 				    offsetof(struct xdp_md, data_meta)),
+ 			BPF_LDX_MEM(BPF_W, BPF_REG_3, BPF_REG_1,
+ 				    offsetof(struct xdp_md, data)),
+ 			BPF_MOV64_IMM(BPF_REG_5, 42),
+ 			BPF_MOV64_IMM(BPF_REG_6, 24),
+ 			BPF_STX_MEM(BPF_DW, BPF_REG_10, BPF_REG_5, -8),
+ 			BPF_STX_XADD(BPF_DW, BPF_REG_10, BPF_REG_6, -8),
+ 			BPF_LDX_MEM(BPF_DW, BPF_REG_5, BPF_REG_10, -8),
+ 			BPF_JMP_IMM(BPF_JGT, BPF_REG_5, 100, 6),
+ 			BPF_ALU64_REG(BPF_ADD, BPF_REG_2, BPF_REG_5),
+ 			BPF_MOV64_REG(BPF_REG_5, BPF_REG_2),
+ 			BPF_MOV64_REG(BPF_REG_6, BPF_REG_2),
+ 			BPF_ALU64_IMM(BPF_ADD, BPF_REG_6, 8),
+ 			BPF_JMP_REG(BPF_JGT, BPF_REG_6, BPF_REG_3, 1),
+ 			BPF_LDX_MEM(BPF_B, BPF_REG_5, BPF_REG_5, 0),
+ 			BPF_MOV64_IMM(BPF_REG_0, 0),
+ 			BPF_EXIT_INSN(),
+ 		},
+ 		.result = ACCEPT,
+ 		.prog_type = BPF_PROG_TYPE_XDP,
+ 	},
+ 	{
+ 		"meta access, test12",
+ 		.insns = {
+ 			BPF_LDX_MEM(BPF_W, BPF_REG_2, BPF_REG_1,
+ 				    offsetof(struct xdp_md, data_meta)),
+ 			BPF_LDX_MEM(BPF_W, BPF_REG_3, BPF_REG_1,
+ 				    offsetof(struct xdp_md, data)),
+ 			BPF_LDX_MEM(BPF_W, BPF_REG_4, BPF_REG_1,
+ 				    offsetof(struct xdp_md, data_end)),
+ 			BPF_MOV64_REG(BPF_REG_5, BPF_REG_3),
+ 			BPF_ALU64_IMM(BPF_ADD, BPF_REG_5, 16),
+ 			BPF_JMP_REG(BPF_JGT, BPF_REG_5, BPF_REG_4, 5),
+ 			BPF_LDX_MEM(BPF_B, BPF_REG_0, BPF_REG_3, 0),
+ 			BPF_MOV64_REG(BPF_REG_5, BPF_REG_2),
+ 			BPF_ALU64_IMM(BPF_ADD, BPF_REG_5, 16),
+ 			BPF_JMP_REG(BPF_JGT, BPF_REG_5, BPF_REG_3, 1),
+ 			BPF_LDX_MEM(BPF_B, BPF_REG_0, BPF_REG_2, 0),
+ 			BPF_MOV64_IMM(BPF_REG_0, 0),
+ 			BPF_EXIT_INSN(),
+ 		},
+ 		.result = ACCEPT,
+ 		.prog_type = BPF_PROG_TYPE_XDP,
+ 	},
+ 	{
+ 		"bpf_exit with invalid return code. test1",
+ 		.insns = {
+ 			BPF_LDX_MEM(BPF_W, BPF_REG_0, BPF_REG_1, 0),
+ 			BPF_EXIT_INSN(),
+ 		},
+ 		.errstr = "R0 has value (0x0; 0xffffffff)",
+ 		.result = REJECT,
+ 		.prog_type = BPF_PROG_TYPE_CGROUP_SOCK,
+ 	},
+ 	{
+ 		"bpf_exit with invalid return code. test2",
+ 		.insns = {
+ 			BPF_LDX_MEM(BPF_W, BPF_REG_0, BPF_REG_1, 0),
+ 			BPF_ALU64_IMM(BPF_AND, BPF_REG_0, 1),
+ 			BPF_EXIT_INSN(),
+ 		},
+ 		.result = ACCEPT,
+ 		.prog_type = BPF_PROG_TYPE_CGROUP_SOCK,
+ 	},
+ 	{
+ 		"bpf_exit with invalid return code. test3",
+ 		.insns = {
+ 			BPF_LDX_MEM(BPF_W, BPF_REG_0, BPF_REG_1, 0),
+ 			BPF_ALU64_IMM(BPF_AND, BPF_REG_0, 3),
+ 			BPF_EXIT_INSN(),
+ 		},
+ 		.errstr = "R0 has value (0x0; 0x3)",
+ 		.result = REJECT,
+ 		.prog_type = BPF_PROG_TYPE_CGROUP_SOCK,
+ 	},
+ 	{
+ 		"bpf_exit with invalid return code. test4",
+ 		.insns = {
+ 			BPF_MOV64_IMM(BPF_REG_0, 1),
+ 			BPF_EXIT_INSN(),
+ 		},
+ 		.result = ACCEPT,
+ 		.prog_type = BPF_PROG_TYPE_CGROUP_SOCK,
+ 	},
+ 	{
+ 		"bpf_exit with invalid return code. test5",
+ 		.insns = {
+ 			BPF_MOV64_IMM(BPF_REG_0, 2),
+ 			BPF_EXIT_INSN(),
+ 		},
+ 		.errstr = "R0 has value (0x2; 0x0)",
+ 		.result = REJECT,
+ 		.prog_type = BPF_PROG_TYPE_CGROUP_SOCK,
+ 	},
+ 	{
+ 		"bpf_exit with invalid return code. test6",
+ 		.insns = {
+ 			BPF_MOV64_REG(BPF_REG_0, BPF_REG_1),
+ 			BPF_EXIT_INSN(),
+ 		},
+ 		.errstr = "R0 is not a known value (ctx)",
+ 		.result = REJECT,
+ 		.prog_type = BPF_PROG_TYPE_CGROUP_SOCK,
+ 	},
+ 	{
+ 		"bpf_exit with invalid return code. test7",
+ 		.insns = {
+ 			BPF_LDX_MEM(BPF_W, BPF_REG_0, BPF_REG_1, 0),
+ 			BPF_LDX_MEM(BPF_W, BPF_REG_2, BPF_REG_1, 4),
+ 			BPF_ALU64_REG(BPF_MUL, BPF_REG_0, BPF_REG_2),
+ 			BPF_EXIT_INSN(),
+ 		},
+ 		.errstr = "R0 has unknown scalar value",
+ 		.result = REJECT,
+ 		.prog_type = BPF_PROG_TYPE_CGROUP_SOCK,
+ 	},
  };
  
  static int probe_filter_length(const struct bpf_insn *fp)