selftests/bpf: Add test coverage for reg_set_min_max handling

Add a test case for the jmp32/k fix to ensure selftests have coverage.

Before fix:

  # ./vmtest.sh -- ./test_progs -t verifier_or_jmp32_k
  [...]
  ./test_progs -t verifier_or_jmp32_k
  tester_init:PASS:tester_log_buf 0 nsec
  process_subtest:PASS:obj_open_mem 0 nsec
  process_subtest:PASS:specs_alloc 0 nsec
  run_subtest:PASS:obj_open_mem 0 nsec
  run_subtest:FAIL:unexpected_load_success unexpected success: 0
  #492/1   verifier_or_jmp32_k/or_jmp32_k: bit ops + branch on unknown value:FAIL
  #492     verifier_or_jmp32_k:FAIL
  Summary: 0/0 PASSED, 0 SKIPPED, 1 FAILED

After fix:

  # ./vmtest.sh -- ./test_progs -t verifier_or_jmp32_k
  [...]
  ./test_progs -t verifier_or_jmp32_k
  #492/1   verifier_or_jmp32_k/or_jmp32_k: bit ops + branch on unknown value:OK
  #492     verifier_or_jmp32_k:OK
  Summary: 1/1 PASSED, 0 SKIPPED, 0 FAILED

Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
Acked-by: John Fastabend <john.fastabend@gmail.com>
Link: https://lore.kernel.org/r/20240613115310.25383-3-daniel@iogearbox.net
Signed-off-by: Alexei Starovoitov <ast@kernel.org>

diff --git a/tools/testing/selftests/bpf/prog_tests/verifier.c b/tools/testing/selftests/bpf/prog_tests/verifier.c
index 1c9c4ec1be11ed5aed370daedd6c5780173dc253..98ef39efa77e8440f0007a092b88f7ff0a30c253 100644 (file)
--- a/tools/testing/selftests/bpf/prog_tests/verifier.c
+++ b/tools/testing/selftests/bpf/prog_tests/verifier.c
@@ -53,6 +53,7 @@
 #include "verifier_movsx.skel.h"
 #include "verifier_netfilter_ctx.skel.h"
 #include "verifier_netfilter_retcode.skel.h"
+#include "verifier_or_jmp32_k.skel.h"
 #include "verifier_precision.skel.h"
 #include "verifier_prevent_map_lookup.skel.h"
 #include "verifier_raw_stack.skel.h"
@@ -170,6 +171,7 @@ void test_verifier_meta_access(void)          { RUN(verifier_meta_access); }
 void test_verifier_movsx(void)                 { RUN(verifier_movsx); }
 void test_verifier_netfilter_ctx(void)        { RUN(verifier_netfilter_ctx); }
 void test_verifier_netfilter_retcode(void)    { RUN(verifier_netfilter_retcode); }
+void test_verifier_or_jmp32_k(void)           { RUN(verifier_or_jmp32_k); }
 void test_verifier_precision(void)            { RUN(verifier_precision); }
 void test_verifier_prevent_map_lookup(void)   { RUN(verifier_prevent_map_lookup); }
 void test_verifier_raw_stack(void)            { RUN(verifier_raw_stack); }

diff --git a/tools/testing/selftests/bpf/progs/verifier_or_jmp32_k.c b/tools/testing/selftests/bpf/progs/verifier_or_jmp32_k.c
new file mode 100644 (file)
index 0000000..f37713a
--- /dev/null
+++ b/tools/testing/selftests/bpf/progs/verifier_or_jmp32_k.c
@@ -0,0 +1,41 @@
+// SPDX-License-Identifier: GPL-2.0
+
+#include <linux/bpf.h>
+#include <bpf/bpf_helpers.h>
+#include "bpf_misc.h"
+
+SEC("socket")
+__description("or_jmp32_k: bit ops + branch on unknown value")
+__failure
+__msg("R0 invalid mem access 'scalar'")
+__naked void or_jmp32_k(void)
+{
+       asm volatile ("                                 \
+       r0 = 0xffffffff;                                \
+       r0 /= 1;                                        \
+       r1 = 0;                                         \
+       w1 = -1;                                        \
+       w1 >>= 1;                                       \
+       w0 &= w1;                                       \
+       w0 |= 2;                                        \
+       if w0 != 0x7ffffffd goto l1;                    \
+       r0 = 1;                                         \
+       exit;                                           \
+l3:                                                    \
+       r0 = 5;                                         \
+       *(u64*)(r0 - 8) = r0;                           \
+       exit;                                           \
+l2:                                                    \
+       w0 -= 0xe;                                      \
+       if w0 == 1 goto l3;                             \
+       r0 = 4;                                         \
+       exit;                                           \
+l1:                                                    \
+       w0 -= 0x7ffffff0;                               \
+       if w0 s>= 0xe goto l2;                          \
+       r0 = 3;                                         \
+       exit;                                           \
+"      ::: __clobber_all);
+}
+
+char _license[] SEC("license") = "GPL";