libmount: properly canonicalize source and target

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

6 files changed, 68 insertions, 21 deletions

diff --git a/shlibs/mount/src/cache.c b/shlibs/mount/src/cache.c
index 3ed69e1b..9e20a2ae 100644
--- a/shlibs/mount/src/cache.c
+++ b/shlibs/mount/src/cache.c
@@ -406,6 +406,8 @@ char *mnt_get_fstype(const char *devname, int *ambi, mnt_cache *cache)
 	char *type = NULL;
 	int rc;
 
+	DBG(CACHE, mnt_debug_h(cache, "get %s FS type", devname));
+
 	if (cache)
 		return mnt_cache_find_tag_value(cache, devname, "TYPE");
 
@@ -444,6 +446,8 @@ char *mnt_resolve_path(const char *path, mnt_cache *cache)
 
 	assert(path);
 
+	DBG(CACHE, mnt_debug_h(cache, "resolving path %s", path));
+
 	if (!path)
 		return NULL;
 	if (cache)
@@ -489,6 +493,9 @@ char *mnt_resolve_tag(const char *token, const char *value, mnt_cache *cache)
 	assert(token);
 	assert(value);
 
+	DBG(CACHE, mnt_debug_h(cache, "resolving tag token=%s value=%s",
+				token, value));
+
 	if (!token || !value)
 		return NULL;
 
diff --git a/shlibs/mount/src/context.c b/shlibs/mount/src/context.c
index deeb606c..82a47a0e 100644
--- a/shlibs/mount/src/context.c
+++ b/shlibs/mount/src/context.c
@@ -843,7 +843,7 @@ int mnt_context_set_mountdata(mnt_context *cxt, void *data)
  */
 int mnt_context_prepare_srcpath(mnt_context *cxt)
 {
-	const char *path = NULL, *type;
+	const char *path = NULL;
 	mnt_cache *cache;
 	const char *t, *v, *src;
 	int rc = 0;
@@ -859,16 +859,15 @@ int mnt_context_prepare_srcpath(mnt_context *cxt)
 
 	src = mnt_fs_get_source(cxt->fs);
 
-	/* ignore filesystems without a real source or MS_PROPAGATION stuff */
-	if (!src ||
-	    (cxt->fs->flags & (MNT_FS_PSEUDO | MNT_FS_NET)) ||
-	    (cxt->mountflags & (MS_BIND | MS_MOVE | MS_PROPAGATION)))
+	/* ignore filesystems without source or filesystems
+	 * where the source is quasi-path (//foo/bar)
+	 */
+	if (!src || (cxt->fs->flags & MNT_FS_NET))
 		return 0;
 
 	DBG(CXT, mnt_debug_h(cxt, "srcpath '%s'", src));
 
 	cache = mnt_context_get_cache(cxt);
-	type = mnt_fs_get_fstype(cxt->fs);
 
 	if (!mnt_fs_get_tag(cxt->fs, &t, &v)) {
 		/*
@@ -879,28 +878,29 @@ int mnt_context_prepare_srcpath(mnt_context *cxt)
 
 		rc = path ? mnt_fs_set_source(cxt->fs, path) : -EINVAL;
 
-	} else if (!type || (strncmp(type, "9p", 2) &&
-			     strncmp(type, "nfs", 3) &&
-			     strncmp(type, "cifs", 4) &&
-			     strncmp(type, "smbfs", 5))) {
+	} else if (cache) {
 		/*
 		 * Source is PATH (canonicalize)
 		 */
-		if (cache) {
-			path = mnt_resolve_path(src, cache);
-			if (strcmp(path, src))
-				rc = mnt_fs_set_source(cxt->fs, path);
-		}
-	}
+		path = mnt_resolve_path(src, cache);
+		if (path && strcmp(path, src))
+			rc = mnt_fs_set_source(cxt->fs, path);
+	 }
 
 	if (rc) {
-		DBG(CXT, mnt_debug_h(cxt, "failed to prepare srcpath"));
+		DBG(CXT, mnt_debug_h(cxt, "failed to prepare srcpath [rc=%d]", rc));
 		return rc;
 	}
 
 	if (!path)
 		path = src;
 
+	if ((cxt->mountflags & (MS_BIND | MS_MOVE | MS_PROPAGATION)) ||
+	    (cxt->fs->flags & MNT_FS_PSEUDO)) {
+		DBG(CXT, mnt_debug_h(cxt, "PROPAGATION/pseudo FS source: %s", path));
+		return rc;
+	}
+
 	/*
 	 * Initialize loop device
 	 */
@@ -912,6 +912,40 @@ int mnt_context_prepare_srcpath(mnt_context *cxt)
 	return 0;
 }
 
+int mnt_context_prepare_target(mnt_context *cxt)
+{
+	const char *tgt;
+	mnt_cache *cache;
+	int rc = 0;
+
+	assert(cxt);
+	assert(cxt->fs);
+	assert((cxt->flags & MNT_FL_MOUNTFLAGS_MERGED));
+
+	if (!cxt || !cxt->fs)
+		return -EINVAL;
+
+	DBG(CXT, mnt_debug_h(cxt, "preparing target path"));
+
+	tgt = mnt_fs_get_target(cxt->fs);
+	if (!tgt)
+		return 0;
+
+	cache = mnt_context_get_cache(cxt);
+	if (cache) {
+		char *path = mnt_resolve_path(tgt, cache);
+		if (strcmp(path, tgt))
+			rc = mnt_fs_set_target(cxt->fs, path);
+	}
+
+	if (rc)
+		DBG(CXT, mnt_debug_h(cxt, "failed to prepare target"));
+	else
+		DBG(CXT, mnt_debug_h(cxt, "final target '%s'",
+					mnt_fs_get_target(cxt->fs)));
+	return 0;
+}
+
 int mnt_context_guess_fstype(mnt_context *cxt)
 {
 	char *type;
diff --git a/shlibs/mount/src/context_mount.c b/shlibs/mount/src/context_mount.c
index 574a8142..5f6ba696 100644
--- a/shlibs/mount/src/context_mount.c
+++ b/shlibs/mount/src/context_mount.c
@@ -454,6 +454,8 @@ int mnt_context_do_mount(mnt_context *cxt)
 	if (!rc)
 		rc = mnt_context_prepare_srcpath(cxt);
 	if (!rc)
+	       rc = mnt_context_prepare_target(cxt);
+	if (!rc)
 		rc = mnt_context_guess_fstype(cxt);
 	if (!rc)
 		rc = mnt_context_prepare_helper(cxt, "mount", NULL);
diff --git a/shlibs/mount/src/context_umount.c b/shlibs/mount/src/context_umount.c
index 9bbdc29a..9b411d86 100644
--- a/shlibs/mount/src/context_umount.c
+++ b/shlibs/mount/src/context_umount.c
@@ -469,6 +469,8 @@ int mnt_context_do_umount(mnt_context *cxt)
 		rc = mnt_context_merge_mountflags(cxt);
 	if (!rc)
 		rc = evaluate_permissions(cxt);
+	if (!rc)
+	       rc = mnt_context_prepare_target(cxt);
 	if (!rc && !cxt->helper)
 		rc = mnt_context_prepare_helper(cxt, "umount", NULL);
 /* TODO
diff --git a/shlibs/mount/src/mountP.h b/shlibs/mount/src/mountP.h
index f9e3a3f7..c1a864ae 100644
--- a/shlibs/mount/src/mountP.h
+++ b/shlibs/mount/src/mountP.h
@@ -310,6 +310,7 @@ extern int __mnt_fs_set_fstype_ptr(mnt_fs *fs, char *fstype);
 
 /* context.c */
 extern int mnt_context_prepare_srcpath(mnt_context *cxt);
+extern int mnt_context_prepare_target(mnt_context *cxt);
 extern int mnt_context_guess_fstype(mnt_context *cxt);
 extern int mnt_context_prepare_helper(mnt_context *cxt, const char *name, const char *type);
 extern int mnt_context_prepare_update(mnt_context *cxt);
diff --git a/shlibs/mount/src/utils.c b/shlibs/mount/src/utils.c
index 99708333..48c37de3 100644
--- a/shlibs/mount/src/utils.c
+++ b/shlibs/mount/src/utils.c
@@ -137,11 +137,12 @@ int mnt_fstype_is_netfs(const char *type)
 {
 	if (!type)
 		return 0;
-	if (strcmp(type, "cifs")  == 0 ||
+	if (strcmp(type, "cifs")   == 0 ||
 	    strcmp(type, "smbfs")  == 0 ||
-	    strncmp(type, "nfs", 3) == 0 ||
-	    strcmp(type, "afs") == 0 ||
-	    strcmp(type, "ncpfs") == 0)
+	    strncmp(type,"nfs", 3) == 0 ||
+	    strcmp(type, "afs")    == 0 ||
+	    strcmp(type, "ncpfs")  == 0 ||
+	    strncmp(type,"9p", 2)  == 0)
 		return 1;
 	return 0;
 }