[3.13.y-ckt stable] Patch "udf: Verify i_size when loading inode" has been added to staging queue

[Kamal Mostafa]

This is a note to let you know that I have just added a patch titled

    udf: Verify i_size when loading inode

to the linux-3.13.y-queue branch of the 3.13.y-ckt extended stable tree 
which can be found at:

 http://kernel.ubuntu.com/git?p=ubuntu/linux.git;a=shortlog;h=refs/heads/linux-3.13.y-queue

This patch is scheduled to be released in version 3.13.11-ckt16.

If you, or anyone else, feels it should not be added to this tree, please 
reply to this email.

For more information about the 3.13.y-ckt tree, see
https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable

Thanks.
-Kamal

------

>From d4fccab8df703016ea0f909dc732ca58dbda0c4b Mon Sep 17 00:00:00 2001
From: Jan Kara <jack at suse.cz>
Date: Fri, 19 Dec 2014 12:03:53 +0100
Subject: udf: Verify i_size when loading inode

commit e159332b9af4b04d882dbcfe1bb0117f0a6d4b58 upstream.

Verify that inode size is sane when loading inode with data stored in
ICB. Otherwise we may get confused later when working with the inode and
inode size is too big.

Reported-by: Carl Henrik Lunde <chlunde at ping.uio.no>
Signed-off-by: Jan Kara <jack at suse.cz>
[ luis: backported to 3.16:
  - Adjusted exit paths as commit 6d3d5e860a11 ("udf: Make udf_read_inode()
    and udf_iget() return error") is not present in 3.16 kernel ]
Signed-off-by: Luis Henriques <luis.henriques at canonical.com>
Signed-off-by: Kamal Mostafa <kamal at canonical.com>
---
 fs/udf/inode.c | 18 ++++++++++++++++++
 1 file changed, 18 insertions(+)

diff --git a/fs/udf/inode.c b/fs/udf/inode.c
index 55ce50d..cc2ae84 100644
--- a/fs/udf/inode.c
+++ b/fs/udf/inode.c
@@ -1482,6 +1482,24 @@ reread:
 		iinfo->i_checkpoint = le32_to_cpu(efe->checkpoint);
 	}

+	/* Sanity checks for files in ICB so that we don't get confused later */
+	if (iinfo->i_alloc_type == ICBTAG_FLAG_AD_IN_ICB) {
+		/*
+		 * For file in ICB data is stored in allocation descriptor
+		 * so sizes should match
+		 */
+		if (iinfo->i_lenAlloc != inode->i_size) {
+			make_bad_inode(inode);
+			return;
+		}
+		/* File in ICB has to fit in there... */
+		if (inode->i_size > inode->i_sb->s_blocksize -
+					udf_file_entry_alloc_offset(inode)) {
+			make_bad_inode(inode);
+			return;
+		}
+	}
+
 	switch (fe->icbTag.fileType) {
 	case ICBTAG_FILE_TYPE_DIRECTORY:
 		inode->i_op = &udf_dir_inode_operations;
--
1.9.1