aboutsummaryrefslogtreecommitdiff
path: root/drivers/acpi
diff options
context:
space:
mode:
authorPuneet Kumar <puneetster@chromium.org>2013-11-15 11:41:29 -0800
committerGreg Kroah-Hartman <gregkh@linuxfoundation.org>2013-11-29 11:27:55 -0800
commit04b4bc701219792b9019cdb750c012a2ecab6357 (patch)
tree60e6cb887332a8d8a6a54c1f1f6efb74f8532cdf /drivers/acpi
parent539ddb09c46389cc22d35543e40ccde2c2e20244 (diff)
ACPI / EC: Ensure lock is acquired before accessing ec struct members
commit 36b15875a7819a2ec4cb5748ff7096ad7bd86cbb upstream. A bug was introduced by commit b76b51ba0cef ('ACPI / EC: Add more debug info and trivial code cleanup') that erroneously caused the struct member to be accessed before acquiring the required lock. This change fixes it by ensuring the lock acquisition is done first. Found by Aaron Durbin <adurbin@chromium.org> Fixes: b76b51ba0cef ('ACPI / EC: Add more debug info and trivial code cleanup') References: http://crbug.com/319019 Signed-off-by: Puneet Kumar <puneetster@chromium.org> Reviewed-by: Aaron Durbin <adurbin@chromium.org> [olof: Commit message reworded a bit] Signed-off-by: Olof Johansson <olof@lixom.net> Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com> Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/acpi')
-rw-r--r--drivers/acpi/ec.c3
1 files changed, 2 insertions, 1 deletions
diff --git a/drivers/acpi/ec.c b/drivers/acpi/ec.c
index a06d9837470..15986f32009 100644
--- a/drivers/acpi/ec.c
+++ b/drivers/acpi/ec.c
@@ -175,9 +175,10 @@ static void start_transaction(struct acpi_ec *ec)
static void advance_transaction(struct acpi_ec *ec, u8 status)
{
unsigned long flags;
- struct transaction *t = ec->curr;
+ struct transaction *t;
spin_lock_irqsave(&ec->lock, flags);
+ t = ec->curr;
if (!t)
goto unlock;
if (t->wlen > t->wi) {