John Hubbard c1a214ad82 mei: fix use-after-free in mei_cl_write
KASAN reports a use-after-free during startup, in mei_cl_write:

    BUG: KASAN: use-after-free in mei_cl_write+0x601/0x870 [mei]
       (drivers/misc/mei/client.c:1770)

This is caused by commit 98e70866aacb ("mei: add support for variable
length mei headers."), which changed the return value from len, to
buf->size. That ends up using a stale buf pointer, because blocking
call, the cb (callback) is deleted in me_cl_complete() function.

However, fortunately, len remains unchanged throughout the function
(and I don't see anything else that would require re-reading buf->size
either), so the fix is to simply revert the change, and return len, as
before.

Fixes: 98e70866aacb ("mei: add support for variable length mei headers.")
CC: Arnd Bergmann <arnd@arndb.de>
CC: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: John Hubbard <jhubbard@nvidia.com>
Signed-off-by: Tomas Winkler <tomas.winkler@intel.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2018-09-12 09:14:24 +02:00
2018-08-18 15:55:59 -07:00
2018-08-25 13:40:38 -07:00
2018-09-06 14:01:15 -07:00
2018-09-09 05:42:11 -07:00
2018-09-08 15:52:45 -07:00
2018-04-15 17:21:30 -07:00
2018-08-25 18:13:10 -07:00
2017-11-17 17:45:29 -08:00
2018-09-09 17:26:43 -07:00

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.
See Documentation/00-INDEX for a list of what is contained in each file.

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.
Description
No description provided
Readme 5.7 GiB
Languages
C 97.6%
Assembly 1%
Shell 0.5%
Python 0.3%
Makefile 0.3%