Qiujun Huang 047affa0ef fbcon: fix null-ptr-deref in fbcon_switch ... commit b139f8b00d upstream. Set logo_shown to FBCON_LOGO_CANSHOW when the vc was deallocated. syzkaller report: https://lkml.org/lkml/2020/3/27/403 general protection fault, probably for non-canonical address 0xdffffc000000006c: 0000 [#1] SMP KASAN KASAN: null-ptr-deref in range [0x0000000000000360-0x0000000000000367] RIP: 0010:fbcon_switch+0x28f/0x1740 drivers/video/fbdev/core/fbcon.c:2260 Call Trace: redraw_screen+0x2a8/0x770 drivers/tty/vt/vt.c:1008 vc_do_resize+0xfe7/0x1360 drivers/tty/vt/vt.c:1295 fbcon_init+0x1221/0x1ab0 drivers/video/fbdev/core/fbcon.c:1219 visual_init+0x305/0x5c0 drivers/tty/vt/vt.c:1062 do_bind_con_driver+0x536/0x890 drivers/tty/vt/vt.c:3542 do_take_over_console+0x453/0x5b0 drivers/tty/vt/vt.c:4122 do_fbcon_takeover+0x10b/0x210 drivers/video/fbdev/core/fbcon.c:588 fbcon_fb_registered+0x26b/0x340 drivers/video/fbdev/core/fbcon.c:3259 do_register_framebuffer drivers/video/fbdev/core/fbmem.c:1664 [inline] register_framebuffer+0x56e/0x980 drivers/video/fbdev/core/fbmem.c:1832 dlfb_usb_probe.cold+0x1743/0x1ba3 drivers/video/fbdev/udlfb.c:1735 usb_probe_interface+0x310/0x800 drivers/usb/core/driver.c:374 accessing vc_cons[logo_shown].d->vc_top causes the bug. Reported-by: syzbot+732528bae351682f1f27@syzkaller.appspotmail.com Signed-off-by: Qiujun Huang <hqjagain@gmail.com> Acked-by: Sam Ravnborg <sam@ravnborg.org> Cc: stable@vger.kernel.org Signed-off-by: Daniel Vetter <daniel.vetter@ffwll.ch> Link: https://patchwork.freedesktop.org/patch/msgid/20200329085647.25133-1-hqjagain@gmail.com Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>		2020-04-13 10:48:14 +02:00
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backlight	- Core Frameworks	2019-09-23 19:33:56 -07:00
console	vgacon: Fix a UAF in vgacon_invert_region	2020-03-12 13:00:19 +01:00
fbdev	fbcon: fix null-ptr-deref in fbcon_switch	2020-04-13 10:48:14 +02:00
logo	video/logo: do not generate unneeded logo C files	2019-10-05 15:29:49 +09:00
Kconfig	treewide: Add SPDX license identifier - Makefile/Kconfig	2019-05-21 10:50:46 +02:00
Makefile	License cleanup: add SPDX GPL-2.0 license identifier to files with no license	2017-11-02 11:10:55 +01:00
display_timing.c	treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 428	2019-06-05 17:37:16 +02:00
hdmi.c	video/hdmi: Fix AVI bar unpack	2019-12-17 19:56:42 +01:00
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	treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 428	2019-06-05 17:37:16 +02:00
vgastate.c	Video: vgastate: fixed a spacing coding style	2018-10-08 12:57:35 +02:00
videomode.c	treewide: Replace GPLv2 boilerplate/reference with SPDX - rule 428	2019-06-05 17:37:16 +02:00