From: Konstantin Khorenko <[email protected]> memfd_test.c: In function 'mfd_fail_grow_write.part.0': memfd_test.c:685:13: warning: '<unknown>' may be used uninitialized [-Wmaybe-uninitialized] 685 | l = pwrite(fd, buf, mfd_def_size * 8, 0); | ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
pwrite() is declared with attribute 'access (read_only, 2, 3)', so GCC knows it reads from the buffer. malloc() returns uninitialized memory, hence the warning. Use calloc() to zero-initialize the buffer. The actual contents don't matter here since the test verifies that pwrite() fails on a sealed memfd. Signed-off-by: Konstantin Khorenko <[email protected]> Signed-off-by: Eva Kurchatova <[email protected]> --- tools/testing/selftests/memfd/memfd_test.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/tools/testing/selftests/memfd/memfd_test.c b/tools/testing/selftests/memfd/memfd_test.c index 2ca07ea7202a..cdab3a837624 100644 --- a/tools/testing/selftests/memfd/memfd_test.c +++ b/tools/testing/selftests/memfd/memfd_test.c @@ -688,9 +688,9 @@ static void mfd_assert_grow_write(int fd) if (hugetlbfs_test) return; - buf = malloc(mfd_def_size * 8); + buf = calloc(1, mfd_def_size * 8); if (!buf) { - printf("malloc(%zu) failed: %m\n", mfd_def_size * 8); + printf("calloc(1, %zu) failed: %m\n", mfd_def_size * 8); abort(); } -- 2.54.0
