fbdev fixes and updates for kernel v5.20-rc1

The two major changes in this patchset corrects VGA modes, color
handling and various other smaller fixes in the Atari framebuffer (by
Geert Uytterhoeven), and devm_* conversion, platform data fixes and
header cleanups in the imxfb driver (by Uwe Kleine-K├Ânig).

Other small patches clean up code in sa1100fb, cirrusfb and omapfb,
fix a refcount leak in amba-clcd (by Liang He), and adds parameter
checks to arkfb, i740fb, vt8623fb and s3fb (by Zheyu Ma).
video: fbdev: s3fb: Check the size of screen before memset_io()

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: a268422de8bf ("fbdev driver for S3 Trio/Virge")
Signed-off-by: Zheyu Ma <zheyuma97@gmail.com>
Signed-off-by: Helge Deller <deller@gmx.de>
1 file changed