Zheyu Ma
5e0da18956
[ Upstream commit6ba592fa01] In the function s3fb_set_par(), the value of 'screen_size' is calculated by the user input. If the user provides the improper value, the value of 'screen_size' may larger than 'info->screen_size', which may cause the following bug: [ 54.083733] BUG: unable to handle page fault for address: ffffc90003000000 [ 54.083742] #PF: supervisor write access in kernel mode [ 54.083744] #PF: error_code(0x0002) - not-present page [ 54.083760] RIP: 0010:memset_orig+0x33/0xb0 [ 54.083782] Call Trace: [ 54.083788] s3fb_set_par+0x1ec6/0x4040 [ 54.083806] fb_set_var+0x604/0xeb0 [ 54.083836] do_fb_ioctl+0x234/0x670 Fix the this by checking the value of 'screen_size' before memset_io(). Fixes:a268422de8("fbdev driver for S3 Trio/Virge") Signed-off-by: Zheyu Ma <zheyuma97@gmail.com> Signed-off-by: Helge Deller <deller@gmx.de> 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.