Re: [LTP] [PATCH v5] statvfs01: Convert to new LTP API

Petr Vorel
2022-12-22T09:49:47Z

Hi Avinesh, Richie,

Generally LGTM, thanks for fixing exfat and vfat.

> > + toolong_fname = SAFE_MALLOC(buf.f_namemax + 1);
However, length could be smaller:
Instead using buf.f_namemax + 1 (1531) also for exfat and vfat,
invalid length is already buf.f_namemax / NLS_MAX_CHARSET_SIZE + 1 (256).

> > + if (fs_type == TST_VFAT_MAGIC || fs_type == TST_EXFAT_MAGIC)
> > + valid_fname = SAFE_MALLOC(buf.f_namemax / NLS_MAX_CHARSET_SIZE - 1);
> > + else
> > + valid_fname = SAFE_MALLOC(buf.f_namemax - 1);

> > - if (TEST_RETURN == -1) {
> > - tst_resm(TFAIL | TTERRNO, "statvfs(%s, ...) failed",
> > - TEST_PATH);
> > - } else {
> > - tst_resm(TPASS, "statvfs(%s, ...) passed", TEST_PATH);
> > - }
> > + memset(toolong_fname, 'b', buf.f_namemax + 1);
> > + if (fs_type == TST_VFAT_MAGIC || fs_type == TST_EXFAT_MAGIC)
> > + memset(valid_fname, 'a', buf.f_namemax / NLS_MAX_CHARSET_SIZE - 1);
> > + else
> > + memset(valid_fname, 'a', buf.f_namemax - 1);
Also valid length is for buf.f_namemax, not buf.f_namemax - 1. I guess -1 is for
\0 (NULL terminator), but tests work even with just buf.f_namemax.

Also adding variable to hold the length makes source more readable.
How about this?

struct statvfs buf;
char *valid_fname, *toolong_fname;
long fs_type;
long valid_len;

fs_type = tst_fs_type(TEST_PATH);

TST_EXP_PASS(statvfs(TEST_PATH, &buf));

valid_len = buf.f_namemax;
if (fs_type == TST_VFAT_MAGIC || fs_type == TST_EXFAT_MAGIC)
valid_len = buf.f_namemax / NLS_MAX_CHARSET_SIZE;

valid_fname = SAFE_MALLOC(valid_len);
memset(valid_fname, 'a', valid_len);

toolong_fname = SAFE_MALLOC(valid_len + 1);
memset(toolong_fname, 'b', valid_len + 1);

Final diff is below.

Kind regards,
Petr

diff --git testcases/kernel/syscalls/statvfs/statvfs01.c testcases/kernel/syscalls/statvfs/statvfs01.c
index 034835da7d..f357855eb1 100644
--- testcases/kernel/syscalls/statvfs/statvfs01.c
+++ testcases/kernel/syscalls/statvfs/statvfs01.c
@@ -25,22 +25,21 @@ static void run(void)
struct statvfs buf;
char *valid_fname, *toolong_fname;
long fs_type;
+ long valid_len;

fs_type = tst_fs_type(TEST_PATH);

TST_EXP_PASS(statvfs(TEST_PATH, &buf));

- toolong_fname = SAFE_MALLOC(buf.f_namemax + 1);
+ valid_len = buf.f_namemax;
if (fs_type == TST_VFAT_MAGIC || fs_type == TST_EXFAT_MAGIC)
- valid_fname = SAFE_MALLOC(buf.f_namemax / NLS_MAX_CHARSET_SIZE - 1);
- else
- valid_fname = SAFE_MALLOC(buf.f_namemax - 1);
+ valid_len = buf.f_namemax / NLS_MAX_CHARSET_SIZE;

- memset(toolong_fname, 'b', buf.f_namemax + 1);
- if (fs_type == TST_VFAT_MAGIC || fs_type == TST_EXFAT_MAGIC)
- memset(valid_fname, 'a', buf.f_namemax / NLS_MAX_CHARSET_SIZE - 1);
- else
- memset(valid_fname, 'a', buf.f_namemax - 1);
+ valid_fname = SAFE_MALLOC(valid_len);
+ memset(valid_fname, 'a', valid_len);
+
+ toolong_fname = SAFE_MALLOC(valid_len + 1);
+ memset(toolong_fname, 'b', valid_len + 1);

TST_EXP_FD(creat(valid_fname, 0444));
SAFE_CLOSE(TST_RET);