| 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: Thu, 10 Feb 2011 17:48:38 -0800
From: Andres Salomon <dilinger@...ued.net>
To: gregkh@...e.de
Cc: linux-kernel@...r.kernel.org, cjb@...top.org,
jon.nettleton@...il.com, devel@...verdev.osuosl.org
Subject: [PATCH 03/10] olpc_dcon: move fb stuff info dcon_priv, and clean up
fb handling
- move fbinfo and ignore_fb_events into dcon_priv
- add calls to {un,}lock_fb_info before calling fb_blank
- fail to load the driver if there are no registered framebuffers
That last one fixes a potential oops, where if the dcon driver loads
without a framebuffer registered, fb_blank will end up being passed a
NULL (and will attempt to dereference it).
Signed-off-by: Andres Salomon <dilinger@...ued.net>
---
drivers/staging/olpc_dcon/olpc_dcon.c | 60 ++++++++++++++++++++------------
1 files changed, 37 insertions(+), 23 deletions(-)
diff --git a/drivers/staging/olpc_dcon/olpc_dcon.c b/drivers/staging/olpc_dcon/olpc_dcon.c
index 710d880..d3c2800 100644
--- a/drivers/staging/olpc_dcon/olpc_dcon.c
+++ b/drivers/staging/olpc_dcon/olpc_dcon.c
@@ -55,6 +55,7 @@ static struct dcon_platform_data *pdata;
struct dcon_priv {
struct i2c_client *client;
+ struct fb_info *fbinfo;
struct work_struct switch_source;
struct notifier_block reboot_nb;
@@ -66,6 +67,8 @@ struct dcon_priv {
/* Current output type; true == mono, false == color */
bool mono;
bool asleep;
+ /* This get set while controlling fb blank state from the driver */
+ bool ignore_fb_events;
};
/* I2C structures */
@@ -78,11 +81,6 @@ static struct platform_device *dcon_device;
/* Backlight device */
static struct backlight_device *dcon_bl_dev;
-static struct fb_info *fbinfo;
-
-/* set this to 1 while controlling fb blank state from this driver */
-static int ignore_fb_events = 0;
-
/* Current source, initialized at probe time */
static int dcon_source;
@@ -346,8 +344,32 @@ void dcon_load_holdoff(void)
mdelay(4);
}
}
-/* Set the source of the display (CPU or DCON) */
+static bool dcon_blank_fb(struct dcon_priv *dcon, bool blank)
+{
+ int err;
+
+ if (!lock_fb_info(dcon->fbinfo)) {
+ dev_err(&dcon->client->dev, "unable to lock framebuffer\n");
+ return false;
+ }
+ console_lock();
+ dcon->ignore_fb_events = true;
+ err = fb_blank(dcon->fbinfo,
+ blank ? FB_BLANK_POWERDOWN : FB_BLANK_UNBLANK);
+ dcon->ignore_fb_events = false;
+ console_unlock();
+ unlock_fb_info(dcon->fbinfo);
+
+ if (err) {
+ dev_err(&dcon->client->dev, "couldn't %sblank framebuffer\n",
+ blank ? "" : "un");
+ return false;
+ }
+ return true;
+}
+
+/* Set the source of the display (CPU or DCON) */
static void dcon_source_switch(struct work_struct *work)
{
struct dcon_priv *dcon = container_of(work, struct dcon_priv,
@@ -391,17 +413,11 @@ static void dcon_source_switch(struct work_struct *work)
*
* For now, we just hope..
*/
- console_lock();
- ignore_fb_events = 1;
- if (fb_blank(fbinfo, FB_BLANK_UNBLANK)) {
- ignore_fb_events = 0;
- console_unlock();
+ if (!dcon_blank_fb(dcon, false)) {
printk(KERN_ERR "olpc-dcon: Failed to enter CPU mode\n");
dcon_pending = DCON_SOURCE_DCON;
return;
}
- ignore_fb_events = 0;
- console_unlock();
/* And turn off the DCON */
pdata->set_dconload(1);
@@ -453,13 +469,7 @@ static void dcon_source_switch(struct work_struct *work)
}
}
- console_lock();
- ignore_fb_events = 1;
- if (fb_blank(fbinfo, FB_BLANK_POWERDOWN))
- printk(KERN_ERR "olpc-dcon: couldn't blank fb!\n");
- ignore_fb_events = 0;
- console_unlock();
-
+ dcon_blank_fb(dcon, true);
printk(KERN_INFO "olpc-dcon: The DCON has control\n");
break;
}
@@ -678,7 +688,7 @@ static int dcon_fb_notifier(struct notifier_block *self,
fbevent_nb);
int *blank = (int *) evdata->data;
if (((event != FB_EVENT_BLANK) && (event != FB_EVENT_CONBLANK)) ||
- ignore_fb_events)
+ dcon->ignore_fb_events)
return 0;
dcon_sleep(dcon, *blank ? true : false);
return 0;
@@ -708,8 +718,12 @@ static int dcon_probe(struct i2c_client *client, const struct i2c_device_id *id)
i2c_set_clientdata(client, dcon);
- if (num_registered_fb >= 1)
- fbinfo = registered_fb[0];
+ if (num_registered_fb < 1) {
+ dev_err(&client->dev, "DCON driver requires a registered fb\n");
+ rc = -EIO;
+ goto einit;
+ }
+ dcon->fbinfo = registered_fb[0];
rc = dcon_hw_init(dcon, 1);
if (rc)
--
1.7.2.3
--
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