[LTP] [PATCH v3 1/1] safe_macros.c: Fix missing ro flag for FUSE mounts

[Petr Vorel]

Hi all,

> The test incorrectly assumes that FUSE mounts are read-only, but the mount
> command does not explicitly set the read-only flag. As a result, the test fails
> when checking `sb_flags` against `MS_RDONLY`.

@Cyril actually v3 is the final version to have a look.

Kind regards,
Petr

> Old behavior:

>     sudo LTP_SINGLE_FS_TYPE=ntfs strace -e trace=mount,statmount -o log.log -s 128 -f ./statmount02
>     ...
>     statmount02.c:47: TFAIL: st_mount->sb_flags (0) != MS_RDONLY (1)
>     ...

> Relevant log excerpt:

>     3890601 mount("/dev/zero", "/tmp/mountBDSEqk", "ntfs", 0, NULL) = -1 ENOTBLK (Block device required)
>     3890608 mount("/dev/loop0", "/tmp/LTP_staTPRruR/mntpoint", "fuseblk", 0, "allow_other,blksize=4096,fd=4,rootmode=40000,user_id=0,group_id=0") = 0
>     3890607 statmount({size=24, mnt_id=0x80010957, param=STATMOUNT_SB_BASIC}, {size=512, mask=STATMOUNT_SB_BASIC, sb_dev_major=7, sb_dev_minor=0, sb_magic=FUSE_SUPER_MAGIC, sb_flags=0}, 512, 0) = 0

> Reviewed-by: Avinesh Kumar <akumar@suse.de>
> Reviewed-by: Petr Vorel <pvorel@suse.cz>
> Signed-off-by: Jan Polensky <japo@linux.ibm.com>
> ---
> Change since v1 (Thanks Cyril & thanks for the ping):
> * Removed restriction for NTFS.
> Change since v2 (Thanks Avinesh):
> * Changed commit title from: "Fix missing ro flag for FUSE NTFS mounts"

>  lib/safe_macros.c | 9 +++++++--
>  1 file changed, 7 insertions(+), 2 deletions(-)

> diff --git a/lib/safe_macros.c b/lib/safe_macros.c
> index d52b55ab70fe..25fad4b7cae0 100644
> --- a/lib/safe_macros.c
> +++ b/lib/safe_macros.c
> @@ -945,10 +945,15 @@ int safe_mount(const char *file, const int lineno, void (*cleanup_fn)(void),
>  	tst_resm_(file, lineno, TINFO, "tst_is_fuse: %d", tst_is_fuse(source));
>  	if (possibly_fuse(filesystemtype)) {
>  		char buf[1024];
> +		const char* mount_fmt;

>  		tst_resm_(file, lineno, TINFO, "Trying FUSE...");
> -		snprintf(buf, sizeof(buf), "mount.%s '%s' '%s'",
> -			filesystemtype, source, target);
> +		if (mountflags == MS_RDONLY)
> +			mount_fmt = "mount.%s -o ro '%s' '%s'";
> +		else
> +			mount_fmt = "mount.%s '%s' '%s'";
> +		snprintf(buf, sizeof(buf), mount_fmt, filesystemtype,
> +				source, target);

>  		rval = tst_system(buf);
>  	tst_resm_(file, lineno, TINFO, "tst_is_fuse: %d", tst_is_fuse(source));