ext4: fix in-superblock mount options processing

[firefly-linux-kernel-4.4.55.git] / fs / ext4 / super.c

diff --git a/fs/ext4/super.c b/fs/ext4/super.c
index c59f864bd0c86d95f3aa9813f512f24e81e7f21c..5a5b8c8d4b0db260661e9b3bf60cc6fd3f87e2c7 100644 (file)
--- a/fs/ext4/super.c
+++ b/fs/ext4/super.c
@@ -3130,7 +3130,7 @@ static int ext4_fill_super(struct super_block *sb, void *data, int silent)
        char *orig_data = kstrdup(data, GFP_KERNEL);
        struct buffer_head *bh;
        struct ext4_super_block *es = NULL;
-       struct ext4_sb_info *sbi;
+       struct ext4_sb_info *sbi = kzalloc(sizeof(*sbi), GFP_KERNEL);
        ext4_fsblk_t block;
        ext4_fsblk_t sb_block = get_sb_block(&data);
        ext4_fsblk_t logical_sb_block;
@@ -3149,16 +3149,14 @@ static int ext4_fill_super(struct super_block *sb, void *data, int silent)
        unsigned int journal_ioprio = DEFAULT_JOURNAL_IOPRIO;
        ext4_group_t first_not_zeroed;
 
-       sbi = kzalloc(sizeof(*sbi), GFP_KERNEL);
-       if (!sbi)
-               goto out_free_orig;
+       if ((data && !orig_data) || !sbi)
+               goto out_free_base;
 
        sbi->s_blockgroup_lock =
                kzalloc(sizeof(struct blockgroup_lock), GFP_KERNEL);
-       if (!sbi->s_blockgroup_lock) {
-               kfree(sbi);
-               goto out_free_orig;
-       }
+       if (!sbi->s_blockgroup_lock)
+               goto out_free_base;
+
        sb->s_fs_info = sbi;
        sbi->s_sb = sb;
        sbi->s_inode_readahead_blks = EXT4_DEF_INODE_READAHEAD_BLKS;
@@ -3304,11 +3302,19 @@ static int ext4_fill_super(struct super_block *sb, void *data, int silent)
         */
        sbi->s_li_wait_mult = EXT4_DEF_LI_WAIT_MULT;
 
-       if (!parse_options((char *) sbi->s_es->s_mount_opts, sb,
-                          &journal_devnum, &journal_ioprio, 0)) {
-               ext4_msg(sb, KERN_WARNING,
-                        "failed to parse options in superblock: %s",
-                        sbi->s_es->s_mount_opts);
+       if (sbi->s_es->s_mount_opts[0]) {
+               char *s_mount_opts = kstrndup(sbi->s_es->s_mount_opts,
+                                             sizeof(sbi->s_es->s_mount_opts),
+                                             GFP_KERNEL);
+               if (!s_mount_opts)
+                       goto failed_mount;
+               if (!parse_options(s_mount_opts, sb, &journal_devnum,
+                                  &journal_ioprio, 0)) {
+                       ext4_msg(sb, KERN_WARNING,
+                                "failed to parse options in superblock: %s",
+                                s_mount_opts);
+               }
+               kfree(s_mount_opts);
        }
        sbi->s_def_mount_opt = sbi->s_mount_opt;
        if (!parse_options((char *) data, sb, &journal_devnum,
@@ -3991,7 +3997,9 @@ no_journal:
 
        if (___ratelimit(&ext4_mount_msg_ratelimit, "EXT4-fs mount"))
                ext4_msg(sb, KERN_INFO, "mounted filesystem with%s. "
-                        "Opts: %s%s%s", descr, sbi->s_es->s_mount_opts,
+                        "Opts: %.*s%s%s", descr,
+                        (int) sizeof(sbi->s_es->s_mount_opts),
+                        sbi->s_es->s_mount_opts,
                         *sbi->s_es->s_mount_opts ? "; " : "", orig_data);
 
        if (es->s_error_count)
@@ -4061,8 +4069,8 @@ failed_mount:
 out_fail:
        sb->s_fs_info = NULL;
        kfree(sbi->s_blockgroup_lock);
+out_free_base:
        kfree(sbi);
-out_free_orig:
        kfree(orig_data);
        return err ? err : ret;
 }