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

    hpfs: better test for errors

to the 3.10-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:
     hpfs-better-test-for-errors.patch
and it can be found in the queue-3.10 subdirectory.

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


>From 3ebacb05044f82c5f0bb456a894eb9dc57d0ed90 Mon Sep 17 00:00:00 2001
From: Mikulas Patocka <[email protected]>
Date: Thu, 4 Jul 2013 18:42:29 +0200
Subject: hpfs: better test for errors

From: Mikulas Patocka <[email protected]>

commit 3ebacb05044f82c5f0bb456a894eb9dc57d0ed90 upstream.

The test if bitmap access is out of bound could errorneously pass if the
device size is divisible by 16384 sectors and we are asking for one bitmap
after the end.

Check for invalid size in the superblock. Invalid size could cause integer
overflows in the rest of the code.

Signed-off-by: Mikulas Patocka <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>

---
 fs/hpfs/map.c   |    3 ++-
 fs/hpfs/super.c |    8 +++++++-
 2 files changed, 9 insertions(+), 2 deletions(-)

--- a/fs/hpfs/map.c
+++ b/fs/hpfs/map.c
@@ -17,7 +17,8 @@ __le32 *hpfs_map_bitmap(struct super_blo
                         struct quad_buffer_head *qbh, char *id)
 {
        secno sec;
-       if (hpfs_sb(s)->sb_chk) if (bmp_block * 16384 > hpfs_sb(s)->sb_fs_size) 
{
+       unsigned n_bands = (hpfs_sb(s)->sb_fs_size + 0x3fff) >> 14;
+       if (hpfs_sb(s)->sb_chk) if (bmp_block >= n_bands) {
                hpfs_error(s, "hpfs_map_bitmap called with bad parameter: %08x 
at %s", bmp_block, id);
                return NULL;
        }
--- a/fs/hpfs/super.c
+++ b/fs/hpfs/super.c
@@ -558,7 +558,13 @@ static int hpfs_fill_super(struct super_
        sbi->sb_cp_table = NULL;
        sbi->sb_c_bitmap = -1;
        sbi->sb_max_fwd_alloc = 0xffffff;
-       
+
+       if (sbi->sb_fs_size >= 0x80000000) {
+               hpfs_error(s, "invalid size in superblock: %08x",
+                       (unsigned)sbi->sb_fs_size);
+               goto bail4;
+       }
+
        /* Load bitmap directory */
        if (!(sbi->sb_bmp_dir = hpfs_load_bitmap_directory(s, 
le32_to_cpu(superblock->bitmaps))))
                goto bail4;


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

queue-3.10/hpfs-better-test-for-errors.patch
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