On Tue, Nov 11, 2025 at 3:40 PM Marat Khalili <[email protected]> wrote: > > > On Mon, Nov 10, 2025 at 9:01 PM Marat Khalili <[email protected]> > > wrote: > > > > > > Left shifts of integer literals and bool values overwriting the sign bit > > > were used multiple times in bpf_jit_arm64.c. E.g.: > > > > > > insn = (!!is64) << 31; > > > > > > where is64 has type bool (double bang is a no-op here). The operand of > > > left shift was promoted to type int, which when 32-bit wide cannot > > > represent the result. Similarly literal integers have int type by > > > default. Sanitizer produced the following diagnostic during runtime > > > (for various lines): > > > > > > lib/bpf/bpf_jit_arm64.c:241:18: runtime error: left shift of 1 by 31 > > > places cannot be represented in type 'int' > > > > Wonder why none of the tests in app/test/test_bpf.c able to catch > > this? The generated ARM opcode looks OK (otherwise tests wont pass). > > Could you check what is missing in the app/test/test_bpf.c? > > That tests do trigger it. > > RTE>>bpf_autotest > ../../src/lib/bpf/bpf_jit_arm64.c:320:18: runtime error: left shift of 1 by > 31 places cannot be represented in type 'int'
This is when ASAN is enabled. Right? Is it really generating BAD opcode(i.e emiter generating bad OPcode) and test fails? > #0 0x22bf59c in mov_imm ../../src/lib/bpf/bpf_jit_arm64.c:320 > #1 0x22bfae0 in emit_mov_imm ../../src/lib/bpf/bpf_jit_arm64.c:378 > #2 0x22c3bfc in emit ../../src/lib/bpf/bpf_jit_arm64.c:1321 > #3 0x22c4314 in __rte_bpf_jit_arm64 ../../src/lib/bpf/bpf_jit_arm64.c:1414 > #4 0x22775c0 in __rte_bpf_jit ../../src/lib/bpf/bpf.c:44 > #5 0x228fbdc in rte_bpf_load ../../src/lib/bpf/bpf_load.c:115 > #6 0x6312f8 in run_test ../../src/app/test/test_bpf.c:3225 > #7 0x631848 in test_bpf ../../src/app/test/test_bpf.c:3269 > [...] > > RTE>>bpf_convert_autotest > ../../src/lib/bpf/bpf_jit_arm64.c:241:18: runtime error: left shift of 1 by > 31 places cannot be represented in type 'int' > #0 0x22bf04c in emit_add_sub_imm ../../src/lib/bpf/bpf_jit_arm64.c:241 > #1 0x22bf270 in emit_mov ../../src/lib/bpf/bpf_jit_arm64.c:267 > #2 0x22bf2a4 in emit_mov_64 ../../src/lib/bpf/bpf_jit_arm64.c:273 > #3 0x22c1a68 in emit_prologue_no_call > ../../src/lib/bpf/bpf_jit_arm64.c:884 > #4 0x22c1c9c in emit_prologue ../../src/lib/bpf/bpf_jit_arm64.c:904 > #5 0x22c327c in emit ../../src/lib/bpf/bpf_jit_arm64.c:1136 > #6 0x22c4314 in __rte_bpf_jit_arm64 ../../src/lib/bpf/bpf_jit_arm64.c:1414 > #7 0x22775c0 in __rte_bpf_jit ../../src/lib/bpf/bpf.c:44 > #8 0x228fbdc in rte_bpf_load ../../src/lib/bpf/bpf_load.c:115 > #9 0x631e7c in test_bpf_match ../../src/app/test/test_bpf.c:3328 > #10 0x632ce8 in test_bpf_filter_sanity ../../src/app/test/test_bpf.c:3376 > #11 0x6331c4 in test_bpf_convert ../../src/app/test/test_bpf.c:3487 > [...]
