28621b38ac
[ Upstream commit 40ec787e1adf302c11668d4cc69838f4d584187d ]
The call to:
size = simple_write_to_buffer(cmdbuf, sizeof(cmdbuf), ppos, buf, size);
will succeed if at least one byte is written to the "cmdbuf" buffer.
The "*ppos" value controls which byte is written. Another problem is
that this code does not check for errors so it's possible for the entire
buffer to be uninitialized.
Inintialize the struct to zero to prevent reading uninitialized stack
data.
Debugfs is normally only writable by root so the impact of this bug is
very minimal.
Fixes: 6cca83d498bd ("Platform: OLPC: move debugfs support from x86 EC driver")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Link: https://lore.kernel.org/r/YthIKn+TfZSZMEcM@kili
Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Hans de Goede <hdegoede@redhat.com>
Signed-off-by: Sasha Levin <sashal@kernel.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.