This is a note to let you know that I've just added the patch titled

    ext4: fix overflow when updating superblock backups after resize

to the 3.17-stable tree which can be found at:
    
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     ext4-fix-overflow-when-updating-superblock-backups-after-resize.patch
and it can be found in the queue-3.17 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <[email protected]> know about it.


>From 9378c6768e4fca48971e7b6a9075bc006eda981d Mon Sep 17 00:00:00 2001
From: Jan Kara <[email protected]>
Date: Thu, 30 Oct 2014 10:52:57 -0400
Subject: ext4: fix overflow when updating superblock backups after resize

From: Jan Kara <[email protected]>

commit 9378c6768e4fca48971e7b6a9075bc006eda981d upstream.

When there are no meta block groups update_backups() will compute the
backup block in 32-bit arithmetics thus possibly overflowing the block
number and corrupting the filesystem. OTOH filesystems without meta
block groups larger than 16 TB should be rare. Fix the problem by doing
the counting in 64-bit arithmetics.

Coverity-id: 741252
Signed-off-by: Jan Kara <[email protected]>
Signed-off-by: Theodore Ts'o <[email protected]>
Reviewed-by: Lukas Czerner <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>

---
 fs/ext4/resize.c |    2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

--- a/fs/ext4/resize.c
+++ b/fs/ext4/resize.c
@@ -1081,7 +1081,7 @@ static void update_backups(struct super_
                        break;
 
                if (meta_bg == 0)
-                       backup_block = group * bpg + blk_off;
+                       backup_block = ((ext4_fsblk_t)group) * bpg + blk_off;
                else
                        backup_block = (ext4_group_first_block_no(sb, group) +
                                        ext4_bg_has_super(sb, group));


Patches currently in stable-queue which might be from [email protected] are

queue-3.17/evm-check-xattr-value-length-and-type-in-evm_inode_setxattr.patch
queue-3.17/ext4-don-t-check-quota-format-when-there-are-no-quota-files.patch
queue-3.17/ext4-fix-oops-when-loading-block-bitmap-failed.patch
queue-3.17/vfs-fix-data-corruption-when-blocksize-pagesize-for-mmaped-data.patch
queue-3.17/ext4-fix-mmap-data-corruption-when-blocksize-pagesize.patch
queue-3.17/ext4-don-t-orphan-or-truncate-the-boot-loader-inode.patch
queue-3.17/ext4-fix-overflow-when-updating-superblock-backups-after-resize.patch
queue-3.17/ext4-grab-missed-write_count-for-ext4_ioc_swap_boot.patch
--
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