f20e67b455
commit acf104c2331c1ba2a667e65dd36139d1555b1432 upstream. Detect file block mappings with a blockcount that's either so large that integer overflows occur or are zero, because neither are valid in the filesystem. Worse yet, attempting directory modifications causes the iext code to trip over the bmbt key handling and takes the filesystem down. We can fix most of this by preventing the bad metadata from entering the incore structures in the first place. Found by setting blockcount=0 in a directory data fork mapping and watching the fireworks. Signed-off-by: Darrick J. Wong <darrick.wong@oracle.com> Reviewed-by: Christoph Hellwig <hch@lst.de> Signed-off-by: Amir Goldstein <amir73il@gmail.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Linux kernel
============
There are several guides for kernel developers and users. These guides can
be rendered in a number of formats, like HTML and PDF. Please read
Documentation/admin-guide/README.rst first.
In order to build the documentation, use ``make htmldocs`` or
``make pdfdocs``. The formatted documentation can also be read online at:
https://www.kernel.org/doc/html/latest/
There are various text files in the Documentation/ subdirectory,
several of them using the Restructured Text markup notation.
Please read the Documentation/process/changes.rst file, as it contains the
requirements for building and running the kernel, and information about
the problems which may result by upgrading your kernel.