Test that frozen and mmap()'ed BPF map can't be mprotect()'ed as writable or
executable memory.
Signed-off-by: Andrii Nakryiko <andriin@xxxxxx>
---
tools/testing/selftests/bpf/prog_tests/mmap.c | 16 ++++++++++++++++
1 file changed, 16 insertions(+)
diff --git a/tools/testing/selftests/bpf/prog_tests/mmap.c b/tools/testing/selftests/bpf/prog_tests/mmap.c
index 16a814eb4d64..1cdb738346a5 100644
--- a/tools/testing/selftests/bpf/prog_tests/mmap.c
+++ b/tools/testing/selftests/bpf/prog_tests/mmap.c
@@ -140,6 +140,22 @@ void test_mmap(void)
goto cleanup;
}
+ map_mmaped = mmap(NULL, map_sz, PROT_READ, MAP_SHARED, data_map_fd, 0);
+ if (CHECK(map_mmaped == MAP_FAILED, "data_mmap",
+ "data_map R/O mmap failed: %d\n", errno)) {
+ map_mmaped = NULL;
+ goto cleanup;
+ }
+ err = mprotect(map_mmaped, map_sz, PROT_WRITE);
+ if (CHECK(!err, "mprotect_wr", "mprotect() succeeded unexpectedly!\n"))
+ goto cleanup;
+ err = mprotect(map_mmaped, map_sz, PROT_EXEC);
+ if (CHECK(!err, "mprotect_ex", "mprotect() succeeded unexpectedly!\n"))
+ goto cleanup;
+ err = munmap(map_mmaped, map_sz);
+ CHECK_FAIL(err);
+ map_mmaped = NULL;
+
bss_data->in_val = 321;
usleep(1);
CHECK_FAIL(bss_data->in_val != 321);
--
2.24.1
