Tetsuo Handa d88ca7e1a2 fbmem: pull fbcon_update_vcs() out of fb_set_var() ... syzbot is reporting OOB read bug in vc_do_resize() [1] caused by memcpy() based on outdated old_{rows,row_size} values, for resize_screen() can recurse into vc_do_resize() which changes vc->vc_{cols,rows} that outdates old_{rows,row_size} values which were saved before calling resize_screen(). Daniel Vetter explained that resize_screen() should not recurse into fbcon_update_vcs() path due to FBINFO_MISC_USEREVENT being still set when calling resize_screen(). Instead of masking FBINFO_MISC_USEREVENT before calling fbcon_update_vcs(), we can remove FBINFO_MISC_USEREVENT by calling fbcon_update_vcs() only if fb_set_var() returned 0. This change assumes that it is harmless to call fbcon_update_vcs() when fb_set_var() returned 0 without reaching fb_notifier_call_chain(). [1] https://syzkaller.appspot.com/bug?id=c70c88cfd16dcf6e1d3c7f0ab8648b3144b5b25e Reported-and-tested-by: syzbot <syzbot+c37a14770d51a085a520@syzkaller.appspotmail.com> Suggested-by: Daniel Vetter <daniel.vetter@ffwll.ch> Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Reported-by: kernel test robot <lkp@intel.com> for missing #include Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch> Link: https://patchwork.freedesktop.org/patch/msgid/075b7e37-3278-cd7d-31ab-c5073cfa8e92@i-love.sakura.ne.jp		2020-08-04 07:37:23 +02:00
..
backlight	video: backlight: tosa_lcd: convert to use i2c_new_client_device()	2020-06-19 09:20:25 +02:00
console	drm-misc-next for v5.9:	2020-06-24 15:45:51 +10:00
fbdev	fbmem: pull fbcon_update_vcs() out of fb_set_var()	2020-08-04 07:37:23 +02:00
logo	.gitignore: add SPDX License Identifier	2020-03-25 11:50:48 +01:00
display_timing.c
hdmi.c	drm-misc-next for v5.9:	2020-06-24 15:45:51 +10:00
Kconfig
Makefile
of_display_timing.c	video: of: display_timing: Don't yell if no timing node is present	2019-07-26 16:32:26 +02:00
of_videomode.c
vgastate.c
videomode.c