libmount: don't pass comments=/x-* to mount.<type> helpers

This patch add a new flag MNT_NOHLPS for mount options map, options
with this flag will not be passed to /sbin/mount.<type> helpers.

Signed-off-by: Karel Zak <kzak@redhat.com>

3 files changed, 38 insertions, 15 deletions

diff --git a/libmount/src/context_mount.c b/libmount/src/context_mount.c
index 17bbd4287..b3a26fcc8 100644
--- a/libmount/src/context_mount.c
+++ b/libmount/src/context_mount.c
@@ -147,26 +147,50 @@ done:
  */
 static int generate_helper_optstr(struct libmnt_context *cxt, char **optstr)
 {
+	struct libmnt_optmap const *maps[1];
+	char *next, *name, *val;
+	size_t namesz, valsz;
 	int rc = 0;
 
 	assert(cxt);
 	assert(cxt->fs);
 	assert(optstr);
 
+	DBG(CXT, mnt_debug_h(cxt, "mount: generate heper mount options"));
+
 	*optstr = mnt_fs_strdup_options(cxt->fs);
 	if (!*optstr)
 		return -ENOMEM;
 
 	if (cxt->flags & MNT_FL_SAVED_USER)
 		rc = mnt_optstr_set_option(optstr, "user", cxt->orig_user);
-	if (rc) {
-		free(*optstr);
-		*optstr = NULL;
+	if (rc)
+		goto err;
+
+	/* remove userspace options with MNT_NOHLPS flag */
+	maps[0] = mnt_get_builtin_optmap(MNT_USERSPACE_MAP);
+	next = *optstr;
+
+	while (!mnt_optstr_next_option(&next, &name, &namesz, &val, &valsz)) {
+		const struct libmnt_optmap *ent;
+
+		mnt_optmap_get_entry(maps, 1, name, namesz, &ent);
+		if (ent && ent->id && (ent->mask & MNT_NOHLPS)) {
+			next = name;
+			rc = mnt_optstr_remove_option_at(optstr, name,
+					val ? val + valsz : name + namesz);
+			if (rc)
+				goto err;
+		}
 	}
+
+	return rc;
+err:
+	free(*optstr);
+	*optstr = NULL;
 	return rc;
 }
 
-
 /*
  * this has to be called before fix_optstr()
  */
diff --git a/libmount/src/libmount.h.in b/libmount/src/libmount.h.in
index 3cc1a79e7..c407b98a9 100644
--- a/libmount/src/libmount.h.in
+++ b/libmount/src/libmount.h.in
@@ -70,6 +70,7 @@ struct libmnt_optmap
 #define MNT_INVERT	(1 << 1) /* invert the mountflag */
 #define MNT_NOMTAB	(1 << 2) /* skip in the mtab option string */
 #define MNT_PREFIX	(1 << 3) /* prefix used for some options (e.g. "x-foo") */
+#define MNT_NOHLPS	(1 << 4) /* don't add the option to mount.<type> helpers command line */
 
 /**
  * libmnt_fs:
diff --git a/libmount/src/optmap.c b/libmount/src/optmap.c
index 7bd4da736..4f11ce598 100644
--- a/libmount/src/optmap.c
+++ b/libmount/src/optmap.c
@@ -117,15 +117,13 @@ static const struct libmnt_optmap linux_flags_map[] =
 
 /*
  * userspace mount option (built-in MNT_USERSPACE_MAP)
- *
- * TODO: offset=, sizelimit=, encryption=, vfs=
  */
 static const struct libmnt_optmap userspace_opts_map[] =
 {
    { "defaults", 0, 0 },               /* default options */
 
-   { "auto",    MNT_MS_NOAUTO, MNT_INVERT | MNT_NOMTAB },  /* Can be mounted using -a */
-   { "noauto",  MNT_MS_NOAUTO, MNT_NOMTAB },               /* Can  only be mounted explicitly */
+   { "auto",    MNT_MS_NOAUTO, MNT_NOHLPS | MNT_INVERT | MNT_NOMTAB },  /* Can be mounted using -a */
+   { "noauto",  MNT_MS_NOAUTO, MNT_NOHLPS | MNT_NOMTAB },  /* Can  only be mounted explicitly */
 
    { "user[=]", MNT_MS_USER },                             /* Allow ordinary user to mount (mtab) */
    { "nouser",  MNT_MS_USER, MNT_INVERT | MNT_NOMTAB },    /* Forbid ordinary user to mount */
@@ -141,19 +139,19 @@ static const struct libmnt_optmap userspace_opts_map[] =
 
    { "_netdev", MNT_MS_NETDEV },                           /* Device requires network */
 
-   { "comment=", MNT_MS_COMMENT, MNT_NOMTAB },             /* fstab comment only */
-   { "x-",      MNT_MS_XCOMMENT, MNT_NOMTAB | MNT_PREFIX }, /* x- options */
+   { "comment=", MNT_MS_COMMENT, MNT_NOHLPS | MNT_NOMTAB },/* fstab comment only */
+   { "x-",      MNT_MS_XCOMMENT, MNT_NOHLPS | MNT_NOMTAB | MNT_PREFIX }, /* x- options */
 
-   { "loop[=]", MNT_MS_LOOP },                             /* use the loop device */
-   { "offset=", MNT_MS_OFFSET, MNT_NOMTAB },		   /* loop device offset */
-   { "sizelimit=", MNT_MS_SIZELIMIT, MNT_NOMTAB },	   /* loop device size limit */
-   { "encryption=", MNT_MS_ENCRYPTION, MNT_NOMTAB },	   /* loop device encryption */
+   { "loop[=]", MNT_MS_LOOP, MNT_NOHLPS },                             /* use the loop device */
+   { "offset=", MNT_MS_OFFSET, MNT_NOHLPS | MNT_NOMTAB },		   /* loop device offset */
+   { "sizelimit=", MNT_MS_SIZELIMIT, MNT_NOHLPS | MNT_NOMTAB },	   /* loop device size limit */
+   { "encryption=", MNT_MS_ENCRYPTION, MNT_NOHLPS | MNT_NOMTAB },	   /* loop device encryption */
 
    { "nofail",  MNT_MS_NOFAIL, MNT_NOMTAB },               /* Do not fail if ENOENT on dev */
 
    { "uhelper=", MNT_MS_UHELPER },			   /* /sbin/umount.<helper> */
 
-   { "helper=", MNT_MS_HELPER },			   /* /sbin/umount.<helper> */
+   { "helper=", MNT_MS_HELPER },			   /* /sbin/mount.<helper> */
 
    { NULL, 0, 0 }
 };