udf: Preserve link count of system files

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>
This commit is contained in:
Jan Kara 2023-01-03 09:56:56 +01:00
parent 256fe4162f
commit fc8033a34a
3 changed files with 10 additions and 3 deletions

View File

@ -1301,6 +1301,7 @@ static int udf_read_inode(struct inode *inode, bool hidden_inode)
ret = -EIO;
goto out;
}
iinfo->i_hidden = hidden_inode;
iinfo->i_unique = 0;
iinfo->i_lenEAttr = 0;
iinfo->i_lenExtents = 0;
@ -1636,8 +1637,12 @@ 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);

View File

@ -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);

View File

@ -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;
__u8 *i_data;
struct kernel_lb_addr i_locStreamdir;
__u64 i_lenStreams;