| Message ID | 20210812140518.183178-3-iii@linux.ibm.com (mailing list archive) |
|---|---|
| State | Changes Requested |
| Delegated to: | BPF |
| Headers | show |
| Series | bpf: clear zext_dst of dead insns | expand |
| Context | Check | Description |
|---|---|---|
| netdev/cover_letter | success | Link |
| netdev/fixes_present | success | Link |
| netdev/patch_count | success | Link |
| netdev/tree_selection | success | Clearly marked for bpf |
| netdev/subject_prefix | success | Link |
| netdev/cc_maintainers | warning | 9 maintainers not CCed: netdev@vger.kernel.org andrii@kernel.org john.fastabend@gmail.com linux-kselftest@vger.kernel.org shuah@kernel.org songliubraving@fb.com yhs@fb.com kpsingh@kernel.org kafai@fb.com |
| netdev/source_inline | success | Was 0 now: 0 |
| netdev/verify_signedoff | success | Link |
| netdev/module_param | success | Was 0 now: 0 |
| netdev/build_32bit | success | Errors and warnings before: 0 this patch: 0 |
| netdev/kdoc | success | Errors and warnings before: 0 this patch: 0 |
| netdev/verify_fixes | success | Link |
| netdev/checkpatch | success | total: 0 errors, 0 warnings, 0 checks, 16 lines checked |
| netdev/build_allmodconfig_warn | success | Errors and warnings before: 0 this patch: 0 |
| netdev/header_inline | success | Link |
On Thu, 2021-08-12 at 16:05 +0200, Ilya Leoshkevich wrote: > Prevent regressions related to zero-extension metadata handling during > dead code sanitization. > > Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com> > --- > tools/testing/selftests/bpf/verifier/dead_code.c | 13 +++++++++++++ > 1 file changed, 13 insertions(+) > > diff --git a/tools/testing/selftests/bpf/verifier/dead_code.c > b/tools/testing/selftests/bpf/verifier/dead_code.c > index 2c8935b3e65d..c642138b7fc2 100644 > --- a/tools/testing/selftests/bpf/verifier/dead_code.c > +++ b/tools/testing/selftests/bpf/verifier/dead_code.c > @@ -159,3 +159,16 @@ > .result = ACCEPT, > .retval = 2, > }, > +{ > + "dead code: zero extension", > + .insns = { > + BPF_MOV64_IMM(BPF_REG_0, 0), > + BPF_JMP_IMM(BPF_JGE, BPF_REG_0, 0, 1), > + BPF_LDX_MEM(BPF_W, BPF_REG_0, BPF_REG_10, 0), > + BPF_EXIT_INSN(), > + }, > + .errstr_unpriv = "invalid read from stack R10 off=0 size=4", > + .result_unpriv = REJECT, > + .result = ACCEPT, > + .retval = 0, > +}, Please disregard this patch: the test does not fail in absence of the fix. What rather fails is: BPF_MOV64_IMM(BPF_REG_0, 0), BPF_STX_MEM(BPF_W, BPF_REG_10, BPF_REG_0, -4), BPF_JMP_IMM(BPF_JGE, BPF_REG_0, 0, 1), BPF_LDX_MEM(BPF_W, BPF_REG_0, BPF_REG_10, -4), BPF_EXIT_INSN(), The difference is that here the dead ldx_w is actually safe. I will send a v3 shortly (I also realized I forgot to tag this series with v2).
diff --git a/tools/testing/selftests/bpf/verifier/dead_code.c b/tools/testing/selftests/bpf/verifier/dead_code.c index 2c8935b3e65d..c642138b7fc2 100644 --- a/tools/testing/selftests/bpf/verifier/dead_code.c +++ b/tools/testing/selftests/bpf/verifier/dead_code.c @@ -159,3 +159,16 @@ .result = ACCEPT, .retval = 2, }, +{ + "dead code: zero extension", + .insns = { + BPF_MOV64_IMM(BPF_REG_0, 0), + BPF_JMP_IMM(BPF_JGE, BPF_REG_0, 0, 1), + BPF_LDX_MEM(BPF_W, BPF_REG_0, BPF_REG_10, 0), + BPF_EXIT_INSN(), + }, + .errstr_unpriv = "invalid read from stack R10 off=0 size=4", + .result_unpriv = REJECT, + .result = ACCEPT, + .retval = 0, +},
Prevent regressions related to zero-extension metadata handling during dead code sanitization. Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com> --- tools/testing/selftests/bpf/verifier/dead_code.c | 13 +++++++++++++ 1 file changed, 13 insertions(+)