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authorHenrik Rydberg <rydberg@euromail.se>2013-09-26 10:33:16 +0400
committerGuenter Roeck <linux@roeck-us.net>2013-09-26 14:48:43 +0400
commit5f4513864304672e6ea9eac60583eeac32e679f2 (patch)
tree65f6f8c23358a92b038a43475bd7715a5f1d05b0 /drivers/hwmon/applesmc.c
parent4b97280675f45c1650ee4e388bd711ecbb18c4b4 (diff)
downloadlinux-5f4513864304672e6ea9eac60583eeac32e679f2.tar.xz
hwmon: (applesmc) Check key count before proceeding
After reports from Chris and Josh Boyer of a rare crash in applesmc, Guenter pointed at the initialization problem fixed below. The patch has not been verified to fix the crash, but should be applied regardless. Reported-by: <jwboyer@fedoraproject.org> Suggested-by: Guenter Roeck <linux@roeck-us.net> Signed-off-by: Henrik Rydberg <rydberg@euromail.se> Cc: stable@vger.kernel.org Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Diffstat (limited to 'drivers/hwmon/applesmc.c')
-rw-r--r--drivers/hwmon/applesmc.c11
1 files changed, 10 insertions, 1 deletions
diff --git a/drivers/hwmon/applesmc.c b/drivers/hwmon/applesmc.c
index 62c2e32e25ef..98814d12a604 100644
--- a/drivers/hwmon/applesmc.c
+++ b/drivers/hwmon/applesmc.c
@@ -525,16 +525,25 @@ static int applesmc_init_smcreg_try(void)
{
struct applesmc_registers *s = &smcreg;
bool left_light_sensor, right_light_sensor;
+ unsigned int count;
u8 tmp[1];
int ret;
if (s->init_complete)
return 0;
- ret = read_register_count(&s->key_count);
+ ret = read_register_count(&count);
if (ret)
return ret;
+ if (s->cache && s->key_count != count) {
+ pr_warn("key count changed from %d to %d\n",
+ s->key_count, count);
+ kfree(s->cache);
+ s->cache = NULL;
+ }
+ s->key_count = count;
+
if (!s->cache)
s->cache = kcalloc(s->key_count, sizeof(*s->cache), GFP_KERNEL);
if (!s->cache)