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| {
| "raw_tracepoint_writable: reject variable offset",
| .insns = {
| /* r6 is our tp buffer */
| BPF_LDX_MEM(BPF_DW, BPF_REG_6, BPF_REG_1, 0),
|
| BPF_LD_MAP_FD(BPF_REG_1, 0),
| /* move the key (== 0) to r10-8 */
| BPF_MOV32_IMM(BPF_REG_0, 0),
| BPF_MOV64_REG(BPF_REG_2, BPF_REG_10),
| BPF_ALU64_IMM(BPF_ADD, BPF_REG_2, -8),
| BPF_STX_MEM(BPF_DW, BPF_REG_2, BPF_REG_0, 0),
| /* lookup in the map */
| BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0,
| BPF_FUNC_map_lookup_elem),
|
| /* exit clean if null */
| BPF_JMP_IMM(BPF_JNE, BPF_REG_0, 0, 1),
| BPF_EXIT_INSN(),
|
| /* shift the buffer pointer to a variable location */
| BPF_LDX_MEM(BPF_W, BPF_REG_0, BPF_REG_0, 0),
| BPF_ALU64_REG(BPF_ADD, BPF_REG_6, BPF_REG_0),
| /* clobber whatever's there */
| BPF_MOV64_IMM(BPF_REG_7, 4242),
| BPF_STX_MEM(BPF_DW, BPF_REG_6, BPF_REG_7, 0),
|
| BPF_MOV64_IMM(BPF_REG_0, 0),
| BPF_EXIT_INSN(),
| },
| .fixup_map_hash_8b = { 1, },
| .prog_type = BPF_PROG_TYPE_RAW_TRACEPOINT_WRITABLE,
| .errstr = "R6 invalid variable buffer offset: off=0, var_off=(0x0; 0xffffffff)",
| },
|
|
