Add a test case to trigger the constant scalar issue which leaves the register in scalar(imm=0,umin=0,umax=1,var_off=(0x0; 0x0)) state. Make use of dead code elimination, so that we can see the verifier bailing out on unfixed kernels. For the condition, we use jle given it checks on umax bound. Before: # ./test_verifier 743 #743/p jump & dead code elimination FAIL Failed to load prog 'Permission denied'! R4 !read_ok verification time 11 usec stack depth 0 processed 13 insns (limit 1000000) max_states_per_insn 0 total_states 1 peak_states 1 mark_read 1 Summary: 0 PASSED, 0 SKIPPED, 1 FAILED After: # ./test_verifier 743 #743/p jump & dead code elimination OK Summary: 1 PASSED, 0 SKIPPED, 0 FAILED
Unified · Split
| @@ -373,3 +373,25 @@ · 372 unmodified lines | |||
| 373 | .result = ACCEPT, | 373 | .result = ACCEPT, |
| 374 | .retval = 3, | 374 | .retval = 3, |
| 375 | }, | 375 | }, |
| 376 | { | ||
| 377 | "jump & dead code elimination", | ||
| 378 | .insns = { | ||
| 379 | BPF_MOV64_IMM(BPF_REG_0, 1), | ||
| 380 | BPF_MOV64_IMM(BPF_REG_3, 0), | ||
| 381 | BPF_ALU64_IMM(BPF_NEG, BPF_REG_3, 0), | ||
| 382 | BPF_ALU64_IMM(BPF_NEG, BPF_REG_3, 0), | ||
| 383 | BPF_ALU64_IMM(BPF_OR, BPF_REG_3, 32767), | ||
| 384 | BPF_JMP_IMM(BPF_JSGE, BPF_REG_3, 0, 1), | ||
| 385 | BPF_EXIT_INSN(), | ||
| 386 | BPF_JMP_IMM(BPF_JSLE, BPF_REG_3, 0x8000, 1), | ||
| 387 | BPF_EXIT_INSN(), | ||
| 388 | BPF_ALU64_IMM(BPF_ADD, BPF_REG_3, -32767), | ||
| 389 | BPF_MOV64_IMM(BPF_REG_0, 2), | ||
| 390 | BPF_JMP_IMM(BPF_JLE, BPF_REG_3, 0, 1), | ||
| 391 | BPF_MOV64_REG(BPF_REG_0, BPF_REG_4), | ||
| 392 | BPF_EXIT_INSN(), | ||
| 393 | }, | ||
| 394 | .prog_type = BPF_PROG_TYPE_SCHED_CLS, | ||
| 395 | .result = ACCEPT, | ||
| 396 | .retval = 2, | ||
| 397 | }, | ||