[patch 50/60] ext4: Check for an valid i_mode when reading the inode from disk

[Greg KH <gregkh@suse.de>]

[-- Attachment #1: ext4-check-for-an-valid-i_mode-when-reading-the-inode-from-disk.patch --]
[-- Type: text/plain, Size: 1248 bytes --]

-stable review patch.  If anyone has any objections, please let us know.

------------------
From: "Theodore Ts'o" <tytso@mit.edu>

(cherry picked from commit 563bdd61fe4dbd6b58cf7eb06f8d8f14479ae1dc)

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>
---
 fs/ext4/inode.c |   10 +++++++++-
 1 file changed, 9 insertions(+), 1 deletion(-)

--- a/fs/ext4/inode.c
+++ b/fs/ext4/inode.c
@@ -4129,7 +4129,8 @@ struct inode *ext4_iget(struct super_blo
 			inode->i_op = &ext4_symlink_inode_operations;
 			ext4_set_aops(inode);
 		}
-	} else {
+	} else if (S_ISCHR(inode->i_mode) || S_ISBLK(inode->i_mode) ||
+	      S_ISFIFO(inode->i_mode) || S_ISSOCK(inode->i_mode)) {
 		inode->i_op = &ext4_special_inode_operations;
 		if (raw_inode->i_block[0])
 			init_special_inode(inode, inode->i_mode,
@@ -4137,6 +4138,13 @@ struct inode *ext4_iget(struct super_blo
 		else
 			init_special_inode(inode, inode->i_mode,
 			   new_decode_dev(le32_to_cpu(raw_inode->i_block[1])));
+	} else {
+		brelse(bh);
+		ret = -EIO;
+		ext4_error(inode->i_sb, __func__,
+			   "bogus i_mode (%o) for inode=%lu",
+			   inode->i_mode, inode->i_ino);
+		goto bad_inode;
 	}
 	brelse (iloc.bh);
 	ext4_set_inode_flags(inode);