diff options
author | Grzegorz Halat | 2019-04-26 16:59:46 +0200 |
---|---|---|
committer | Greg Kroah-Hartman | 2019-05-24 10:06:24 +0200 |
commit | 5e309c6c5ea12515616a4835b7fa2141c8016c94 (patch) | |
tree | d4f3ed300f2fa1b24e137059b38dc1a7b5fd79c3 /drivers/tty/tty_io.c | |
parent | 84ecc2f6eb1cb12e6d44818f94fa49b50f06e6ac (diff) |
vt/fbcon: deinitialize resources in visual_init() after failed memory allocation
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>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/tty/tty_io.c')
0 files changed, 0 insertions, 0 deletions