From 1da1caabbef6d178a6d6a85cf80bed89f489f6be Mon Sep 17 00:00:00 2001
From: Karel Zak <kzak@redhat.com>
Date: Sat, 13 Dec 2008 02:47:42 +0100
Subject: [PATCH] mount: clean up SPEC canonicalization

The SPEC (fsname) field in fstab/mtab could be:

 - devname
 - NAME=value (e.g LABEL, UUID)
 - directory (MS_MOVE, MS_BIND, ..)
 - pseudo-fs keyword (tmpfs, proc, sysfs, ...)

the pseudo-fs keywords shouldn't be canonicalized to absolute path. It
means we have to differ between SPEC and mountpoint (fs_dir).

Unfortunately, the keywords was checked on wrong place. This patch
move this check to the new function canonicalize_spec().

The fsname in mtab entry is canonicalized when the FS type is not
pseudo filesystem.

Signed-off-by: Karel Zak <kzak@redhat.com>
---
 mount/fsprobe.c  |  5 +++++
 mount/fstab.c    | 13 +++++++------
 mount/mount.c    | 18 ++++++++++++------
 mount/realpath.c | 22 ++++++++++++++++------
 mount/realpath.h |  3 ++-
 5 files changed, 42 insertions(+), 19 deletions(-)

diff --git a/mount/fsprobe.c b/mount/fsprobe.c
index 96548647..07ffbd9a 100644
--- a/mount/fsprobe.c
+++ b/mount/fsprobe.c
@@ -170,6 +170,9 @@ fsprobe_get_devname_for_mounting(const char *spec)
 	if (!spec)
 		return NULL;
 
+	if (is_pseudo_fs(spec))
+		return xstrdup(spec);
+
 	if (parse_spec(spec, &name, &value) != 0)
 		return NULL;				/* parse error */
 
@@ -203,6 +206,8 @@ fsprobe_get_devname(const char *spec)
 
 	if (!spec)
 		return NULL;
+	if (is_pseudo_fs(spec))
+		return xstrdup(spec);
 
 	if (parse_spec(spec, &name, &value) != 0)
 		return NULL;				/* parse error */
diff --git a/mount/fstab.c b/mount/fstab.c
index 8c62a9e2..306e7bec 100644
--- a/mount/fstab.c
+++ b/mount/fstab.c
@@ -326,7 +326,7 @@ getfs_by_specdir (const char *spec, const char *dir) {
 	for (mc = mc0->nxt; mc && mc != mc0; mc = mc->nxt) {
 		/* dir */
 		if (!streq(mc->m.mnt_dir, dir)) {
-			char *dr = canonicalize_mountpoint(mc->m.mnt_dir);
+			char *dr = canonicalize(mc->m.mnt_dir);
 			int ok = 0;
 
 			if (streq(dr, dir))
@@ -338,7 +338,7 @@ getfs_by_specdir (const char *spec, const char *dir) {
 
 		/* spec */
 		if (!streq(mc->m.mnt_fsname, spec)) {
-			char *fs = canonicalize(mc->m.mnt_fsname);
+			char *fs = canonicalize_spec(mc->m.mnt_fsname);
 			int ok = 0;
 
 			if (streq(fs, spec))
@@ -372,7 +372,7 @@ getfs_by_dir (const char *dir) {
 		if (streq(mc->m.mnt_dir, dir))
 			return mc;
 
-	cdir = canonicalize_mountpoint(dir);
+	cdir = canonicalize(dir);
 	for (mc = mc0->nxt; mc && mc != mc0; mc = mc->nxt) {
 		if (streq(mc->m.mnt_dir, cdir)) {
 			free(cdir);
@@ -405,7 +405,7 @@ getfs_by_spec (const char *spec) {
 		return mc;
 	}
 
-	cspec = canonicalize(spec);
+	cspec = canonicalize_spec(spec);
 	mc = getfs_by_devname(cspec);
 	free(cspec);
 
@@ -436,7 +436,7 @@ getfs_by_devname (const char *devname) {
 				strncmp(mc->m.mnt_fsname, "UUID=", 5) == 0)
 			continue;
 
-		fs = canonicalize(mc->m.mnt_fsname);
+		fs = canonicalize_spec(mc->m.mnt_fsname);
 		if (streq(fs, devname)) {
 			free(fs);
 			return mc;
@@ -922,7 +922,8 @@ void my_endmntent (mntFILE *mfp) { }
 int my_addmntent (mntFILE *mfp, struct my_mntent *mnt) { return 0; }
 
 char *canonicalize (const char *path) {  return NULL; }
-char *canonicalize_mountpoint (const char *path) { return NULL; }
+char *canonicalize_spec (const char *path) { return NULL; }
+int is_pseudo_fs(const char *type) { return 0; };
 
 int
 main(int argc, char **argv)
diff --git a/mount/mount.c b/mount/mount.c
index ace4b146..947c94a8 100644
--- a/mount/mount.c
+++ b/mount/mount.c
@@ -242,7 +242,7 @@ print_one (const struct my_mntent *me) {
 		printf (" type %s", me->mnt_type);
 	if (me->mnt_opts != NULL)
 		printf (" (%s)", me->mnt_opts);
-	if (list_with_volumelabel) {
+	if (list_with_volumelabel && is_pseudo_fs(me->mnt_type) == 0) {
 		const char *devname = fsprobe_get_devname(me->mnt_fsname);
 
 		if (devname) {
@@ -500,9 +500,11 @@ fix_opts_string (int flags, const char *extra_opts, const char *user) {
 }
 
 static int
-already (const char *spec, const char *node) {
+already (const char *spec0, const char *node0) {
 	struct mntentchn *mc;
 	int ret = 1;
+	char *spec = canonicalize_spec(spec0);
+	char *node = canonicalize(node0);
 
 	if ((mc = getmntfile(node)) != NULL)
 		error (_("mount: according to mtab, "
@@ -514,6 +516,10 @@ already (const char *spec, const char *node) {
 		       spec, mc->m.mnt_dir);
 	else
 		ret = 0;
+
+	free(spec);
+	free(node);
+
 	return ret;
 }
 
@@ -841,7 +847,7 @@ is_mounted_same_loopfile(const char *node0, const char *loopfile, unsigned long
 	char *node;
 	int res = 0;
 
-	node = canonicalize_mountpoint(node0);
+	node = canonicalize(node0);
 
 	/* Search for mountpoint node in mtab,
 	 * procceed if any of these has the loop option set or
@@ -981,8 +987,8 @@ update_mtab_entry(const char *spec, const char *node, const char *type,
 		  const char *opts, int flags, int freq, int pass) {
 	struct my_mntent mnt;
 
-	mnt.mnt_fsname = canonicalize (spec);
-	mnt.mnt_dir = canonicalize_mountpoint (node);
+	mnt.mnt_fsname = is_pseudo_fs(type) ? xstrdup(spec) : canonicalize(spec);
+	mnt.mnt_dir = canonicalize (node);
 	mnt.mnt_type = type;
 	mnt.mnt_opts = opts;
 	mnt.mnt_freq = freq;
@@ -1511,7 +1517,7 @@ mounted (const char *spec0, const char *node0) {
 	if (!spec)
 		return ret;
 
-	node = canonicalize_mountpoint(node0);
+	node = canonicalize(node0);
 
 	mc0 = mtab_head();
 	for (mc = mc0->nxt; mc && mc != mc0; mc = mc->nxt)
diff --git a/mount/realpath.c b/mount/realpath.c
index dbcd42ab..9b46951b 100644
--- a/mount/realpath.c
+++ b/mount/realpath.c
@@ -29,6 +29,19 @@
 # define MAXSYMLINKS 256
 #endif
 
+int
+is_pseudo_fs(const char *type)
+{
+	if (type == NULL || *type == '/')
+		return 0;
+	if (streq(type, "none") ||
+	    streq(type, "proc") ||
+	    streq(type, "tmpfs") ||
+	    streq(type, "sysfs") ||
+	    streq(type, "devpts"))
+		return 1;
+	return 0;
+}
 
 /* Make a canonical pathname from PATH.  Returns a freshly malloced string.
    It is up the *caller* to ensure that the PATH is sensible.  i.e.
@@ -36,15 +49,12 @@
    is not a legal pathname for ``/dev/fd0''.  Anything we cannot parse
    we return unmodified.   */
 char *
-canonicalize_mountpoint (const char *path) {
+canonicalize_spec (const char *path)
+{
 	if (path == NULL)
 		return NULL;
-
-	if (streq(path, "none") ||
-	    streq(path, "proc") ||
-	    streq(path, "devpts"))
+	if (is_pseudo_fs(path))
 		return xstrdup(path);
-
 	return canonicalize(path);
 }
 
diff --git a/mount/realpath.h b/mount/realpath.h
index a8fad639..15450c1d 100644
--- a/mount/realpath.h
+++ b/mount/realpath.h
@@ -8,6 +8,7 @@
 
 extern char *myrealpath(const char *path, char *resolved_path, int m);
 extern char *canonicalize (const char *path);
-extern char *canonicalize_mountpoint (const char *path);
+extern char *canonicalize_spec (const char *path);
+extern int is_pseudo_fs(const char *type);
 
 #endif /* REALPATH_H */
-- 
2.39.5