libmount: fix to work with btrfs subvolume user mounts

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

5 files changed, 31 insertions, 21 deletions

diff --git a/shlibs/mount/src/context.c b/shlibs/mount/src/context.c
index 6ee68c16a..069a88343 100644
--- a/shlibs/mount/src/context.c
+++ b/shlibs/mount/src/context.c
@@ -756,8 +756,8 @@ int mnt_context_set_userspace_mountflags(mnt_context *cxt, unsigned long flags)
  * @cxt: mount context
  * @flags: returns mount flags
  *
- * Converts mount options string to MNT_MS_* flags and bitewise-OR the result with
- * already defined flags (see mnt_context_set_userspace_mountflags()).
+ * Converts mount options string to MNT_MS_* flags and bitewise-OR the result
+ * with already defined flags (see mnt_context_set_userspace_mountflags()).
  *
  * Returns: 0 on success, negative number in case of error.
  */
@@ -995,7 +995,7 @@ int mnt_context_prepare_helper(mnt_context *cxt, const char *name,
 			rc = stat(helper, &st);
 		}
 
-		DBG(CXT, mnt_debug_h(cxt, "%s ... %s", helper,
+		DBG(CXT, mnt_debug_h(cxt, "%-25s ... %s", helper,
 					rc ? "not found" : "found"));
 		if (rc)
 			continue;
diff --git a/shlibs/mount/src/context_mount.c b/shlibs/mount/src/context_mount.c
index cb681e0dd..fb593c3fd 100644
--- a/shlibs/mount/src/context_mount.c
+++ b/shlibs/mount/src/context_mount.c
@@ -126,7 +126,7 @@ done:
 }
 
 /*
- * Converts already evalulated and fixed options to the form that is comaptible
+ * Converts already evalulated and fixed options to the form that is compatible
  * with /sbin/mount.<type> helpers.
  *
  * Retursn newly allocated string.
@@ -160,7 +160,7 @@ static int generate_helper_optstr(mnt_context *cxt, char **optstr)
  */
 static int evaluate_permissions(mnt_context *cxt)
 {
-	unsigned long u_flags;
+	unsigned long u_flags = 0;
 	const char *srcpath;
 
 	assert(cxt);
diff --git a/shlibs/mount/src/context_umount.c b/shlibs/mount/src/context_umount.c
index 7cb4a2a44..ca9ca7749 100644
--- a/shlibs/mount/src/context_umount.c
+++ b/shlibs/mount/src/context_umount.c
@@ -138,7 +138,7 @@ static int mnt_loopdev_associated_fs(const char *devname, mnt_fs *fs)
 static int evaluate_permissions(mnt_context *cxt)
 {
 	mnt_tab *fstab;
-	unsigned long u_flags;
+	unsigned long u_flags = 0;
 	const char *tgt, *src, *optstr;
 	int rc, ok = 0;
 	mnt_fs *fs;
@@ -243,9 +243,11 @@ static int evaluate_permissions(mnt_context *cxt)
 	if (mnt_optstr_get_userspace_mountflags(optstr, &u_flags))
 		goto eperm;
 
-	if (u_flags & MNT_MS_USERS)
-		/* promiscuous setting in fstab */
+	if (u_flags & MNT_MS_USERS) {
+		DBG(CXT, mnt_debug_h(cxt,
+			"umount: promiscuous setting ('users') in fstab"));
 		return 0;
+	}
 	/*
 	 * Check user=<username> setting from mtab if there is user, owner or
 	 * group option in /etc/fstab
@@ -253,14 +255,18 @@ static int evaluate_permissions(mnt_context *cxt)
 	if ((u_flags & MNT_MS_USER) || (u_flags & MNT_MS_OWNER) ||
 	    (u_flags & MNT_MS_GROUP)) {
 
-		char *curr_user = mnt_get_username(getuid());
+		char *curr_user = NULL;
 		char *mtab_user = NULL;
 		size_t sz;
 
+		DBG(CXT, mnt_debug_h(cxt,
+				"umount: checking user=<username> from mtab"));
+
+		curr_user = mnt_get_username(getuid());
+
 		if (!curr_user) {
 			DBG(CXT, mnt_debug_h(cxt, "umount %s: cannot "
-					"convert %d to username",
-					tgt, getuid()));
+				"convert %d to username", tgt, getuid()));
 			goto eperm;
 		}
 
diff --git a/shlibs/mount/src/optstr.c b/shlibs/mount/src/optstr.c
index c5c7c221a..475c4cf1f 100644
--- a/shlibs/mount/src/optstr.c
+++ b/shlibs/mount/src/optstr.c
@@ -520,7 +520,8 @@ int mnt_split_optstr(const char *optstr, char **user, char **vfs, char **fs,
  *
  *	"bind,noexec,foo,bar" --returns->   MS_BIND|MS_NOEXEC
  *
- * Note that @flags are not zeroized by this function.
+ * Note that @flags are not zeroized by this function! This function set/unset
+ * bites in the @flags only.
  *
  * Returns: 0 on success or negative number in case of error
  */
@@ -567,7 +568,8 @@ int mnt_optstr_get_flags(const char *optstr, unsigned long *flags,
  *
  *	"bind,noexec,foo,bar" --returns->   MS_BIND|MS_NOEXEC
  *
- * Note that @flags are not zeroized by this function.
+ * Note that @flags are not zeroized by this function! This function set/unset
+ * bites in the @flags only.
  *
  * Returns: 0 on success or negative number in case of error
  */
@@ -589,7 +591,8 @@ int mnt_optstr_get_mountflags(const char *optstr, unsigned long *flags)
  *
  *	"bind,exec,loop"   --returns->   MNT_MS_LOOP
  *
- * Note that @flags are not zeroized by this function.
+ * Note that @flags are not zeroized by this function! This function set/unset
+ * bites in the @flags only.
  *
  * Returns: 0 on success or negative number in case of error
  */
diff --git a/shlibs/mount/src/tab_update.c b/shlibs/mount/src/tab_update.c
index 7a39c1b06..baf5b0b61 100644
--- a/shlibs/mount/src/tab_update.c
+++ b/shlibs/mount/src/tab_update.c
@@ -35,7 +35,7 @@ struct _mnt_update {
 };
 
 static int utab_new_entry(mnt_fs *fs, unsigned long mountflags, mnt_fs **ent);
-static int set_fs_root(mnt_fs *fs, unsigned long mountflags);
+static int set_fs_root(mnt_fs *result, mnt_fs *fs, unsigned long mountflags);
 
 /**
  * mnt_new_update:
@@ -212,7 +212,7 @@ static int utab_new_entry(mnt_fs *fs, unsigned long mountflags, mnt_fs **ent)
 	u = NULL;
 
 	if (!(mountflags & MS_REMOUNT)) {
-		rc = set_fs_root(*ent, mountflags);
+		rc = set_fs_root(*ent, fs, mountflags);
 		if (rc)
 			goto err;
 	}
@@ -225,7 +225,7 @@ err:
 	return rc;
 }
 
-static int set_fs_root(mnt_fs *fs, unsigned long mountflags)
+static int set_fs_root(mnt_fs *result, mnt_fs *fs, unsigned long mountflags)
 {
 	char *root = NULL, *mnt = NULL;
 	const char *fstype, *optstr;
@@ -233,6 +233,7 @@ static int set_fs_root(mnt_fs *fs, unsigned long mountflags)
 	int rc = -ENOMEM;
 
 	assert(fs);
+	assert(result);
 
 	DBG(UPDATE, mnt_debug("setting FS root"));
 
@@ -248,7 +249,7 @@ static int set_fs_root(mnt_fs *fs, unsigned long mountflags)
 
 		src = mnt_fs_get_srcpath(fs);
 		if (src) {
-			rc = mnt_fs_set_bindsrc(fs, src);
+			rc = mnt_fs_set_bindsrc(result, src);
 			if (rc)
 				goto err;
 			mnt = mnt_get_mountpoint(src);
@@ -268,11 +269,11 @@ static int set_fs_root(mnt_fs *fs, unsigned long mountflags)
 
 		/* set device name and fs */
 		src = mnt_fs_get_srcpath(src_fs);
-		rc = mnt_fs_set_source(fs, src);
+		rc = mnt_fs_set_source(result, src);
 		if (rc)
 			goto err;
 
-		mnt_fs_set_fstype(fs, mnt_fs_get_fstype(src_fs));
+		mnt_fs_set_fstype(result, mnt_fs_get_fstype(src_fs));
 
 		/* on btrfs the subvolume is used as fs-root in
 		 * /proc/self/mountinfo, so we have get the original subvolume
@@ -321,7 +322,7 @@ dflt:
 		if (!root)
 			goto err;
 	}
-	fs->root = root;
+	result->root = root;
 
 	DBG(UPDATE, mnt_debug("FS root result: %s", root));