[PATCH] intel_th: avoid double free in error flow

From: Wen Yang
Date: Tue Nov 19 2019 - 12:35:02 EST


There is a possible double free issue in intel_th_subdevice_alloc:

651 err = intel_th_device_add_resources(thdev, res, subdev->nres);
652 if (err) {
653 put_device(&thdev->dev);
654 goto fail_put_device; ---> freed
655 }
...
687 fail_put_device:
688 put_device(&thdev->dev); ---> double freed
689

This patch fix it by removing the unnecessary put_device().

Fixes: a753bfcfdb1f ("intel_th: Make the switch allocate its subdevices")
Signed-off-by: Wen Yang <wenyang@xxxxxxxxxxxxxxxxx>
Cc: Alexander Shishkin <alexander.shishkin@xxxxxxxxxxxxxxx>
Cc: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
Cc: linux-kernel@xxxxxxxxxxxxxxx
---
drivers/hwtracing/intel_th/core.c | 4 +---
1 file changed, 1 insertion(+), 3 deletions(-)

diff --git a/drivers/hwtracing/intel_th/core.c b/drivers/hwtracing/intel_th/core.c
index d5c1821..98d195c 100644
--- a/drivers/hwtracing/intel_th/core.c
+++ b/drivers/hwtracing/intel_th/core.c
@@ -649,10 +649,8 @@ static inline void intel_th_request_hub_module_flush(struct intel_th *th)
}

err = intel_th_device_add_resources(thdev, res, subdev->nres);
- if (err) {
- put_device(&thdev->dev);
+ if (err)
goto fail_put_device;
- }

if (subdev->type == INTEL_TH_OUTPUT) {
if (subdev->mknode)
--
1.8.3.1