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> Cc: stable <stable@vger.kernel.org> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
parent
5d24f455c1
commit
a1ad1cc970
|
@ -1056,6 +1056,13 @@ static void visual_init(struct vc_data *vc, int num, int init)
|
||||||
vc->vc_screenbuf_size = vc->vc_rows * vc->vc_size_row;
|
vc->vc_screenbuf_size = vc->vc_rows * vc->vc_size_row;
|
||||||
}
|
}
|
||||||
|
|
||||||
|
|
||||||
|
static void visual_deinit(struct vc_data *vc)
|
||||||
|
{
|
||||||
|
vc->vc_sw->con_deinit(vc);
|
||||||
|
module_put(vc->vc_sw->owner);
|
||||||
|
}
|
||||||
|
|
||||||
int vc_allocate(unsigned int currcons) /* return 0 on success */
|
int vc_allocate(unsigned int currcons) /* return 0 on success */
|
||||||
{
|
{
|
||||||
struct vt_notifier_param param;
|
struct vt_notifier_param param;
|
||||||
|
@ -1103,6 +1110,7 @@ int vc_allocate(unsigned int currcons) /* return 0 on success */
|
||||||
|
|
||||||
return 0;
|
return 0;
|
||||||
err_free:
|
err_free:
|
||||||
|
visual_deinit(vc);
|
||||||
kfree(vc);
|
kfree(vc);
|
||||||
vc_cons[currcons].d = NULL;
|
vc_cons[currcons].d = NULL;
|
||||||
return -ENOMEM;
|
return -ENOMEM;
|
||||||
|
@ -1331,9 +1339,8 @@ struct vc_data *vc_deallocate(unsigned int currcons)
|
||||||
param.vc = vc = vc_cons[currcons].d;
|
param.vc = vc = vc_cons[currcons].d;
|
||||||
atomic_notifier_call_chain(&vt_notifier_list, VT_DEALLOCATE, ¶m);
|
atomic_notifier_call_chain(&vt_notifier_list, VT_DEALLOCATE, ¶m);
|
||||||
vcs_remove_sysfs(currcons);
|
vcs_remove_sysfs(currcons);
|
||||||
vc->vc_sw->con_deinit(vc);
|
visual_deinit(vc);
|
||||||
put_pid(vc->vt_pid);
|
put_pid(vc->vt_pid);
|
||||||
module_put(vc->vc_sw->owner);
|
|
||||||
vc_uniscr_set(vc, NULL);
|
vc_uniscr_set(vc, NULL);
|
||||||
kfree(vc->vc_screenbuf);
|
kfree(vc->vc_screenbuf);
|
||||||
vc_cons[currcons].d = NULL;
|
vc_cons[currcons].d = NULL;
|
||||||
|
|
|
@ -1248,7 +1248,7 @@ finished:
|
||||||
if (free_font)
|
if (free_font)
|
||||||
vc->vc_font.data = NULL;
|
vc->vc_font.data = NULL;
|
||||||
|
|
||||||
if (vc->vc_hi_font_mask)
|
if (vc->vc_hi_font_mask && vc->vc_screenbuf)
|
||||||
set_vc_hi_font(vc, false);
|
set_vc_hi_font(vc, false);
|
||||||
|
|
||||||
if (!con_is_bound(&fb_con))
|
if (!con_is_bound(&fb_con))
|
||||||
|
|
Loading…
Reference in New Issue