[PATCH] firmware: arm_scmi: avoid double free in error flow
From: Wen Yang
Date: Mon Nov 25 2019 - 10:54:43 EST
If device_register() fails, both put_device() and kfree()
are called, ending with a double free of the scmi_dev.
Calling kfree() is needed only when a failure happens between the
allocation of the scmi_dev and its registration, so move it to
there and remove it from the error flow.
Fixes: 46edb8d1322c ("firmware: arm_scmi: provide the mandatory device release callback")
Signed-off-by: Wen Yang <wenyang@xxxxxxxxxxxxxxxxx>
Cc: Sudeep Holla <sudeep.holla@xxxxxxx>
Cc: linux-arm-kernel@xxxxxxxxxxxxxxxxxxx
Cc: linux-kernel@xxxxxxxxxxxxxxx
---
drivers/firmware/arm_scmi/bus.c | 8 ++++----
1 file changed, 4 insertions(+), 4 deletions(-)
diff --git a/drivers/firmware/arm_scmi/bus.c b/drivers/firmware/arm_scmi/bus.c
index 92f843ea..7a30952 100644
--- a/drivers/firmware/arm_scmi/bus.c
+++ b/drivers/firmware/arm_scmi/bus.c
@@ -135,8 +135,10 @@ struct scmi_device *
return NULL;
id = ida_simple_get(&scmi_bus_id, 1, 0, GFP_KERNEL);
- if (id < 0)
- goto free_mem;
+ if (id < 0) {
+ kfree(scmi_dev);
+ return NULL;
+ }
scmi_dev->id = id;
scmi_dev->protocol_id = protocol;
@@ -154,8 +156,6 @@ struct scmi_device *
put_dev:
put_device(&scmi_dev->dev);
ida_simple_remove(&scmi_bus_id, id);
-free_mem:
- kfree(scmi_dev);
return NULL;
}
--
1.8.3.1