1{
 2	"raw_tracepoint_writable: reject variable offset",
 3	.insns = {
 4		/* r6 is our tp buffer */
 5		BPF_LDX_MEM(BPF_DW, BPF_REG_6, BPF_REG_1, 0),
 6
 7		BPF_LD_MAP_FD(BPF_REG_1, 0),
 8		/* move the key (== 0) to r10-8 */
 9		BPF_MOV32_IMM(BPF_REG_0, 0),
10		BPF_MOV64_REG(BPF_REG_2, BPF_REG_10),
11		BPF_ALU64_IMM(BPF_ADD, BPF_REG_2, -8),
12		BPF_STX_MEM(BPF_DW, BPF_REG_2, BPF_REG_0, 0),
13		/* lookup in the map */
14		BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0,
15			     BPF_FUNC_map_lookup_elem),
16
17		/* exit clean if null */
18		BPF_JMP_IMM(BPF_JNE, BPF_REG_0, 0, 1),
19		BPF_EXIT_INSN(),
20
21		/* shift the buffer pointer to a variable location */
22		BPF_LDX_MEM(BPF_W, BPF_REG_0, BPF_REG_0, 0),
23		BPF_ALU64_REG(BPF_ADD, BPF_REG_6, BPF_REG_0),
24		/* clobber whatever's there */
25		BPF_MOV64_IMM(BPF_REG_7, 4242),
26		BPF_STX_MEM(BPF_DW, BPF_REG_6, BPF_REG_7, 0),
27
28		BPF_MOV64_IMM(BPF_REG_0, 0),
29		BPF_EXIT_INSN(),
30	},
31	.fixup_map_hash_8b = { 1, },
32	.prog_type = BPF_PROG_TYPE_RAW_TRACEPOINT_WRITABLE,
33	.errstr = "R6 invalid variable buffer offset: off=0, var_off=(0x0; 0xffffffff)",
34},