Grzegorz Halat ff818b449a vt/fbcon: deinitialize resources in visual_init() after failed memory allocation ... commit a1ad1cc970 upstream. After memory allocation failure vc_allocate() doesn't clean up data which has been initialized in visual_init(). In case of fbcon this leads to divide-by-0 in fbcon_init() on next open of the same tty. memory allocation in vc_allocate() may fail here: 1097: vc->vc_screenbuf = kzalloc(vc->vc_screenbuf_size, GFP_KERNEL); on next open() fbcon_init() skips vc_font.data initialization: 1088: if (!p->fontdata) { division by zero in fbcon_init() happens here: 1149: new_cols /= vc->vc_font.width; Additional check is needed in fbcon_deinit() to prevent usage of uninitialized vc_screenbuf: 1251: if (vc->vc_hi_font_mask && vc->vc_screenbuf) 1252: set_vc_hi_font(vc, false); Crash: #6 [ffffc90001eafa60] divide_error at ffffffff81a00be4 [exception RIP: fbcon_init+463] RIP: ffffffff814b860f RSP: ffffc90001eafb18 RFLAGS: 00010246 ... #7 [ffffc90001eafb60] visual_init at ffffffff8154c36e #8 [ffffc90001eafb80] vc_allocate at ffffffff8154f53c #9 [ffffc90001eafbc8] con_install at ffffffff8154f624 ... Signed-off-by: Grzegorz Halat <ghalat@redhat.com> Reviewed-by: Oleksandr Natalenko <oleksandr@redhat.com> Acked-by: Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com> Cc: stable <stable@vger.kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>		2019-06-09 09:17:21 +02:00
..
.gitignore
consolemap.c	treewide: kmalloc() -> kmalloc_array()	2018-06-12 16:19:22 -07:00
cp437.uni
defkeymap.c_shipped
defkeymap.map
keyboard.c	tty/vt: fix write/write race in ioctl(KDSKBSENT) handler	2019-05-22 07:37:41 +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
selection.c	vt: selection: take screen contents from uniscr if available	2018-07-21 09:18:27 +02:00
vc_screen.c	vt: unicode fallback for scrollback	2018-06-28 21:38:12 +09:00
vt.c	vt/fbcon: deinitialize resources in visual_init() after failed memory allocation	2019-06-09 09:17:21 +02:00
vt_ioctl.c	tty: vt_ioctl: fix potential Spectre v1	2018-09-18 15:51:30 +02:00