[LTP] [PATCH v2] tst_test.c: Set system default umaks to 0022

[Petr Vorel]

Hi Wei,

> Some system's default umask is 0077, this will trigger issues for LTP case.

> Example 1:
> cgroup_core01.c will report following error msg:
> cgroup_core01.c:50: TBROK: openat(21</sys/fs/cgroup/memory/ltp/test-3519/child_b>, 'tasks', 2, 0): EACCES (13)

> Detail reason:
> Code:
> cg_child_a = tst_cg_group_mk(tst_cg, "child_a");
> cg_child_b = tst_cg_group_mk(tst_cg, "child_b");

> Result:
> wegao:/sys/fs/cgroup # ll ltp/test-25304/
> drwx------ 2 root root 0 Feb 10 10:37 child_a   <<<<<< group and other has no any permission
> drwx------ 2 root root 0 Feb 10 10:38 child_b

> Code:
> SAFE_CG_FCHOWN(cg_child_a, "cgroup.procs",  nobody_uid, -1);
> SAFE_CG_FCHOWN(cg_child_b, "cgroup.procs",  nobody_uid, -1);

> Result:
> wegao:/sys/fs/cgroup # ll ltp/test-26388/child_a/
> total 0
> -rw-r--r-- 1 nobody root 0 Feb 10 10:44 cgroup.procs  <<<<<<

> Code:
> SAFE_SETEUID(nobody_uid); <<<< after switch to nobody then can not access child_{a,b} or any file
> under child_{a,b}

> Result:
> nobody@wegao:/sys/fs/cgroup/ltp/test-26730> ll child_a/  <<< nobody has no permission on child_a
> ls: cannot open directory 'child_a/': Permission denied

> Code:
> loops = SAFE_CG_OPEN(cg_child_b, "cgroup.procs", O_RDWR, fds);
> Result:
> cgroup_core01.c:76: TBROK: openat(9</sys/fs/cgroup/ltp/test-26388/child_b>, 'cgroup.procs', 2, 0): EACCES (13)

> Example 2:
> chdir01
> chdir01.c:107: TFAIL: nobody: chdir("testfile") returned unexpected error: EACCES (13)

> Reason:
> susetest:/tmp/LTP_chd5JtblL/mntpoint # mount | grep loop0
> /dev/loop0 on /tmp/LTP_chd5JtblL/mntpoint type vfat (rw,relatime,fmask=0077,dmask=0077,codepage=437,iocharset=iso8859-1,shortname=mixed,errors=remount-ro)
> /dev/loop0 on /var/tmp/LTP_chd5JtblL/mntpoint type vfat (rw,relatime,fmask=0077,dmask=0077,codepage=437,iocharset=iso8859-1,shortname=mixed,errors=remount-ro)

> susetest:/tmp/LTP_chd5JtblL # ll
> total 307216
> drwx------ 4 root root     16384 Dec 31  1969 mntpoint <<<< nobody has no permission on mount directory
> -rw------- 1 root root 314572800 Feb 19 04:51 test_dev.img

> susetest:/tmp/LTP_chd5JtblL/mntpoint # ll
> total 16
> -rwx------ 1 root root    0 Feb 19 04:53 aa
> drwx------ 2 root root 8192 Feb 19 04:50 keep_out
> drwx------ 2 root root 8192 Feb 19 04:50 subdir
> -rwx------ 1 root root    0 Feb 19 04:50 testfile <<<< nobody has no permission on testfile

> Signed-off-by: Wei Gao <wegao@suse.com>
> ---
>  lib/tst_test.c | 2 ++
>  1 file changed, 2 insertions(+)

> diff --git a/lib/tst_test.c b/lib/tst_test.c
> index edb42f7f4..e03fd93e7 100644
> --- a/lib/tst_test.c
> +++ b/lib/tst_test.c
> @@ -1174,6 +1174,8 @@ static void do_setup(int argc, char *argv[])
>  {
>  	char *tdebug_env = getenv("LTP_ENABLE_DEBUG");

> +	umask(0022);

I don't think this is a good idea. Changing umask() in the library can influent
tests. Could you please instead add umask(0) (to reset umask) on the tests which
need it? The way it's done in open07.c.

Kind regards,
Petr