| lists.openwall.net | lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC | |
|
Open Source and information security mailing list archives
| ||
|
Date: Fri, 25 Jan 2013 11:43:44 +1000
From: Dave Airlie <airlied@...il.com>
To: linux-fbdev@...r.kernel.org
Cc: dri-devel@...ts.sf.net, linux-kernel@...r.kernel.org,
Dave Airlie <airlied@...il.com>
Subject: [PATCH] fbcon: fix locking harder
Okay so Alan's patch handled the case where there was no registered fbcon,
however the other path entered in set_con2fb_map pit.
In there we called fbcon_takeover, but we also took the console lock in a couple
of places. So push the console lock out to the callers of set_con2fb_map,
this means fbmem and switcheroo needed to take the lock around the fb notifier
entry points that lead to this.
This should fix the efifb regression seen by Maarten.
Signed-off-by: Dave Airlie <airlied@...hat.com>
---
drivers/gpu/vga/vga_switcheroo.c | 3 +++
drivers/video/console/fbcon.c | 11 ++++++++---
drivers/video/fbmem.c | 2 ++
3 files changed, 13 insertions(+), 3 deletions(-)
diff --git a/drivers/gpu/vga/vga_switcheroo.c b/drivers/gpu/vga/vga_switcheroo.c
index fa60add..cf787e1 100644
--- a/drivers/gpu/vga/vga_switcheroo.c
+++ b/drivers/gpu/vga/vga_switcheroo.c
@@ -25,6 +25,7 @@
#include <linux/fb.h>
#include <linux/pci.h>
+#include <linux/console.h>
#include <linux/vga_switcheroo.h>
#include <linux/vgaarb.h>
@@ -337,8 +338,10 @@ static int vga_switchto_stage2(struct vga_switcheroo_client *new_client)
if (new_client->fb_info) {
struct fb_event event;
+ console_lock();
event.info = new_client->fb_info;
fb_notifier_call_chain(FB_EVENT_REMAP_ALL_CONSOLE, &event);
+ console_unlock();
}
ret = vgasr_priv.handler->switchto(new_client->id);
diff --git a/drivers/video/console/fbcon.c b/drivers/video/console/fbcon.c
index 2aef9ca..2e2d959 100644
--- a/drivers/video/console/fbcon.c
+++ b/drivers/video/console/fbcon.c
@@ -842,6 +842,8 @@ static void con2fb_init_display(struct vc_data *vc, struct fb_info *info,
*
* Maps a virtual console @unit to a frame buffer device
* @newidx.
+ *
+ * This should be called with the console lock held.
*/
static int set_con2fb_map(int unit, int newidx, int user)
{
@@ -859,7 +861,7 @@ static int set_con2fb_map(int unit, int newidx, int user)
if (!search_for_mapped_con() || !con_is_bound(&fb_con)) {
info_idx = newidx;
- return fbcon_takeover(0);
+ return do_fbcon_takeover(0);
}
if (oldidx != -1)
@@ -867,7 +869,6 @@ static int set_con2fb_map(int unit, int newidx, int user)
found = search_fb_in_map(newidx);
- console_lock();
con2fb_map[unit] = newidx;
if (!err && !found)
err = con2fb_acquire_newinfo(vc, info, unit, oldidx);
@@ -894,7 +895,6 @@ static int set_con2fb_map(int unit, int newidx, int user)
if (!search_fb_in_map(info_idx))
info_idx = newidx;
- console_unlock();
return err;
}
@@ -3019,6 +3019,7 @@ static inline int fbcon_unbind(void)
}
#endif /* CONFIG_VT_HW_CONSOLE_BINDING */
+/* called with console_lock held */
static int fbcon_fb_unbind(int idx)
{
int i, new_idx = -1, ret = 0;
@@ -3045,6 +3046,7 @@ static int fbcon_fb_unbind(int idx)
return ret;
}
+/* called with console_lock held */
static int fbcon_fb_unregistered(struct fb_info *info)
{
int i, idx;
@@ -3082,6 +3084,7 @@ static int fbcon_fb_unregistered(struct fb_info *info)
return 0;
}
+/* called with console_lock held */
static void fbcon_remap_all(int idx)
{
int i;
@@ -3126,6 +3129,7 @@ static inline void fbcon_select_primary(struct fb_info *info)
}
#endif /* CONFIG_FRAMEBUFFER_DETECT_PRIMARY */
+/* called with console_lock held */
static int fbcon_fb_registered(struct fb_info *info)
{
int ret = 0, i, idx;
@@ -3278,6 +3282,7 @@ static int fbcon_event_notify(struct notifier_block *self,
ret = fbcon_fb_unregistered(info);
break;
case FB_EVENT_SET_CONSOLE_MAP:
+ /* called with console lock held */
con2fb = event->data;
ret = set_con2fb_map(con2fb->console - 1,
con2fb->framebuffer, 1);
diff --git a/drivers/video/fbmem.c b/drivers/video/fbmem.c
index 070b9a1..dc61c12 100644
--- a/drivers/video/fbmem.c
+++ b/drivers/video/fbmem.c
@@ -1177,8 +1177,10 @@ static long do_fb_ioctl(struct fb_info *info, unsigned int cmd,
event.data = &con2fb;
if (!lock_fb_info(info))
return -ENODEV;
+ console_lock();
event.info = info;
ret = fb_notifier_call_chain(FB_EVENT_SET_CONSOLE_MAP, &event);
+ console_unlock();
unlock_fb_info(info);
break;
case FBIOBLANK:
--
1.8.1
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@...r.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/
Powered by blists - more mailing lists