udf: Fold udf_getblk() into udf_bread()

commit 32f123a3f34283f9c6446de87861696f0502b02e upstream.

udf_getblk() has a single call site. Fold it there.

Signed-off-by: Jan Kara <jack@suse.cz>
[acsjakub: backport-adjusting changes
 udf_getblk() has changed between 6.1 and the backported commit, namely
 in commit 541e047b14c8 ("udf: Use udf_map_block() in udf_getblk()")
 Backport using the form of udf_getblk present in 6.1., that means use
 udf_get_block() instead of udf_map_block() and use dummy in buffer_new()
 and buffer_mapped(). ]
Closes: https://syzkaller.appspot.com/bug?extid=a38e34ca637c224f4a79
Signed-off-by: Jakub Acs <acsjakub@amazon.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/fs/udf/inode.c b/fs/udf/inode.c
index d7d6ccd0af06495dec1c1a0e5cde5083e7ad80cd..e2ac428f3809942fffd0cb58fdbe96753fe9c58e 100644 (file)
--- a/fs/udf/inode.c
+++ b/fs/udf/inode.c
@@ -369,29 +369,6 @@ abort:
        return err;
 }
 
-static struct buffer_head *udf_getblk(struct inode *inode, udf_pblk_t block,
-                                     int create, int *err)
-{
-       struct buffer_head *bh;
-       struct buffer_head dummy;
-
-       dummy.b_state = 0;
-       dummy.b_blocknr = -1000;
-       *err = udf_get_block(inode, block, &dummy, create);
-       if (!*err && buffer_mapped(&dummy)) {
-               bh = sb_getblk(inode->i_sb, dummy.b_blocknr);
-               if (buffer_new(&dummy)) {
-                       lock_buffer(bh);
-                       memset(bh->b_data, 0x00, inode->i_sb->s_blocksize);
-                       set_buffer_uptodate(bh);
-                       unlock_buffer(bh);
-                       mark_buffer_dirty_inode(bh, inode);
-               }
-               return bh;
-       }
-
-       return NULL;
-}
 
 /* Extend the file with new blocks totaling 'new_block_bytes',
  * return the number of extents added
@@ -1108,11 +1085,30 @@ struct buffer_head *udf_bread(struct inode *inode, udf_pblk_t block,
                              int create, int *err)
 {
        struct buffer_head *bh = NULL;
+       struct buffer_head dummy;
 
-       bh = udf_getblk(inode, block, create, err);
-       if (!bh)
+       dummy.b_state = 0;
+       dummy.b_blocknr = -1000;
+
+       *err = udf_get_block(inode, block, &dummy, create);
+       if (*err || !buffer_mapped(&dummy))
                return NULL;
 
+       bh = sb_getblk(inode->i_sb, dummy.b_blocknr);
+       if (!bh) {
+               *err = -ENOMEM;
+               return NULL;
+       }
+
+       if (buffer_new(&dummy)) {
+               lock_buffer(bh);
+               memset(bh->b_data, 0x00, inode->i_sb->s_blocksize);
+               set_buffer_uptodate(bh);
+               unlock_buffer(bh);
+               mark_buffer_dirty_inode(bh, inode);
+               return bh;
+       }
+
        if (bh_read(bh, 0) >= 0)
                return bh;