Re: [PATCH 5.15.y] fs/ntfs3: Fix shift-out-of-bounds in ntfs_fill_super

[Greg KH <gregkh@linuxfoundation.org>]

On Sun, Mar 09, 2025 at 03:56:36PM +0100, Miguel García wrote:
> From: Konstantin Komarov <almaz.alexandrovich@paragon-software.com>
> 
> commit 91a4b1ee78cb ("fs/ntfs3: Fix shift-out-of-bounds in ntfs_fill_super")
> 
> This patch is a backport and fixes an UBSAN warning about shift-out-of-bounds in
> ntfs_fill_super() function of the NTFS3 driver. The original code
> incorrectly calculated MFT record size, causing undefined behavior
> when performing bit shifts with values that exceed type limits.
> 
> The fix has been verified by executing the syzkaller reproducer test case.
> After applying this patch, the system successfully handles the test case
> without kernel panic or UBSAN warnings.
> 
> Bug: https://syzkaller.appspot.com/bug?extid=010986becd65dbf9464b
> Reported-by: syzbot+010986becd65dbf9464b@syzkaller.appspotmail.com
> Cc: <stable@vger.kernel.org>
> Signed-off-by: Konstantin Komarov <almaz.alexandrovich@paragon-software.com>
> Signed-off-by: Miguel Garcia Roman <miguelgarciaroman8@gmail.com>
> (cherry picked from commit 91a4b1ee78cb100b19b70f077c247f211110348f)
> ---
>  fs/ntfs3/ntfs_fs.h |  2 ++
>  fs/ntfs3/super.c   | 63 +++++++++++++++++++++++++++++++++++-----------
>  2 files changed, 50 insertions(+), 15 deletions(-)

We need a 6.1.y version of this first.  Please submit that first and
then resend this for older kernels.

thanks,

greg k-h