libmount: fix mtab update for "none" source

tab_parse.c:mnt_parse_mountinfo_line parses "none" in src as NULL,

tab_update.c:fprintf_mtab_fs sets m1 to NULL instead of "none" and
returns -ENOMEM
tab_update.c:update_table says "write entry failed: Success", as errno
hasn't been set, and gotos to leave, leaving mtab not updated.

Addresses-debian-bug: 634871
Reported-by: Tomas Janousek <tomi@nomi.cz>
Signed-off-by: Karel Zak <kzak@redhat.com>

diff --git a/libmount/src/tab_update.c b/libmount/src/tab_update.c
index 88125bfbbe44bf20d963830a636e9cebb1f3abf3..39d61e66c6c995eb8cd6b11a40f4ed7253ef29f3 100644 (file)
--- a/libmount/src/tab_update.c
+++ b/libmount/src/tab_update.c
@@ -409,21 +409,21 @@ err:
  */
 static int fprintf_mtab_fs(FILE *f, struct libmnt_fs *fs)
 {
-       char *o;
+       const char *o, *src, *fstype;
        char *m1, *m2, *m3, *m4;
        int rc;
 
        assert(fs);
        assert(f);
 
-       o = mnt_fs_strdup_options(fs);
-       if (!o)
-               return -ENOMEM;
+       src = mnt_fs_get_source(fs);
+       fstype = mnt_fs_get_fstype(fs);
+       o = mnt_fs_get_options(fs);
 
-       m1 = mangle(mnt_fs_get_source(fs));
+       m1 = src ? mangle(src) : "none";
        m2 = mangle(mnt_fs_get_target(fs));
-       m3 = mangle(mnt_fs_get_fstype(fs));
-       m4 = mangle(o);
+       m3 = fstype ? mangle(fstype) : "none";
+       m4 = o ? mangle(o) : "rw";
 
        if (m1 && m2 && m3 && m4) {
                rc = fprintf(f, "%s %s %s %s %d %d\n",
@@ -435,11 +435,13 @@ static int fprintf_mtab_fs(FILE *f, struct libmnt_fs *fs)
        } else
                rc = -ENOMEM;
 
-       free(o);
-       free(m1);
+       if (src)
+               free(m1);
        free(m2);
-       free(m3);
-       free(m4);
+       if (fstype)
+               free(m3);
+       if (o)
+               free(m4);
 
        return rc;
 }