udf: Preserve link count of system files

commit fc8033a34a3ca7d23353e645e6dde5d364ac5f12 upstream.

System files in UDF filesystem have link count 0. To not confuse VFS we
fudge the link count to be 1 when reading such inodes however we forget
to restore the link count of 0 when writing such inodes. Fix that.

CC: stable@vger.kernel.org
Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/fs/udf/inode.c b/fs/udf/inode.c
index 82b1613a012fdabf835a1d263fe0b2a688a388c6..c7115b5bedc1364be7e4a72dc7b76a2922b215de 100644 (file)
--- a/fs/udf/inode.c
+++ b/fs/udf/inode.c
@@ -1388,6 +1388,7 @@ reread:
                ret = -EIO;
                goto out;
        }
+       iinfo->i_hidden = hidden_inode;
        iinfo->i_unique = 0;
        iinfo->i_lenEAttr = 0;
        iinfo->i_lenExtents = 0;
@@ -1723,8 +1724,12 @@ static int udf_update_inode(struct inode *inode, int do_sync)
 
        if (S_ISDIR(inode->i_mode) && inode->i_nlink > 0)
                fe->fileLinkCount = cpu_to_le16(inode->i_nlink - 1);
-       else
-               fe->fileLinkCount = cpu_to_le16(inode->i_nlink);
+       else {
+               if (iinfo->i_hidden)
+                       fe->fileLinkCount = cpu_to_le16(0);
+               else
+                       fe->fileLinkCount = cpu_to_le16(inode->i_nlink);
+       }
 
        fe->informationLength = cpu_to_le64(inode->i_size);
 

diff --git a/fs/udf/super.c b/fs/udf/super.c
index 5193b94c06834cdb90c103f8c20a5c7fb3bc4b21..0f8b3cb355852acb362b7fbc6f8f7f23fdfdc7cd 100644 (file)
--- a/fs/udf/super.c
+++ b/fs/udf/super.c
@@ -147,6 +147,7 @@ static struct inode *udf_alloc_inode(struct super_block *sb)
        ei->i_next_alloc_goal = 0;
        ei->i_strat4096 = 0;
        ei->i_streamdir = 0;
+       ei->i_hidden = 0;
        init_rwsem(&ei->i_data_sem);
        ei->cached_extent.lstart = -1;
        spin_lock_init(&ei->i_extent_cache_lock);

diff --git a/fs/udf/udf_i.h b/fs/udf/udf_i.h
index 4245d1f632589d557de419c3f4961dbf3cfbb8ab..0372d0d14f7251f274c9787d0e47d294dae3be8e 100644 (file)
--- a/fs/udf/udf_i.h
+++ b/fs/udf/udf_i.h
@@ -44,7 +44,8 @@ struct udf_inode_info {
        unsigned                i_use : 1;      /* unallocSpaceEntry */
        unsigned                i_strat4096 : 1;
        unsigned                i_streamdir : 1;
-       unsigned                reserved : 25;
+       unsigned                i_hidden : 1;   /* hidden system inode */
+       unsigned                reserved : 24;
        union {
                struct short_ad *i_sad;
                struct long_ad          *i_lad;