udf: Fix loading of special inodes

Some UDF media have special inodes (like VAT or metadata partition
inodes) whose link_count is 0. Thus commit 4071b9136223 (udf: Properly
detect stale inodes) broke loading these inodes because udf_iget()
started returning -ESTALE for them. Since we still need to properly
detect stale inodes queried by NFS, create two variants of udf_iget() -
one which is used for looking up special inodes (which ignores
link_count == 0) and one which is used for other cases which return
ESTALE when link_count == 0.

Fixes: 4071b913622316970d0e1919f7d82b4403fec5f2
CC: stable@vger.kernel.org
Signed-off-by: Jan Kara <jack@suse.cz>

1 files changed, 12 insertions, 1 deletions

diff --git a/fs/udf/udfdecl.h b/fs/udf/udfdecl.h
index 742557be9936..1cc3c993ebd0 100644
--- a/fs/udf/udfdecl.h
+++ b/fs/udf/udfdecl.h
@@ -138,7 +138,18 @@ extern int udf_write_fi(struct inode *inode, struct fileIdentDesc *,
 /* file.c */
 extern long udf_ioctl(struct file *, unsigned int, unsigned long);
 /* inode.c */
-extern struct inode *udf_iget(struct super_block *, struct kernel_lb_addr *);
+extern struct inode *__udf_iget(struct super_block *, struct kernel_lb_addr *,
+                                bool hidden_inode);
+static inline struct inode *udf_iget_special(struct super_block *sb,
+                                             struct kernel_lb_addr *ino)
+{
+        return __udf_iget(sb, ino, true);
+}
+static inline struct inode *udf_iget(struct super_block *sb,
+                                     struct kernel_lb_addr *ino)
+{
+        return __udf_iget(sb, ino, false);
+}
 extern int udf_expand_file_adinicb(struct inode *);
 extern struct buffer_head *udf_expand_dir_adinicb(struct inode *, int *, int *);
 extern struct buffer_head *udf_bread(struct inode *, int, int, int *);