2021-02-08 06:36:17

by Rajan Vaja

Subject: [PATCH] drivers: firmware: xilinx: Fix dereferencing freed memory

From: Tejas Patel <[email protected]>

Fix smatch warning:
drivers/firmware/xilinx/zynqmp.c:1288 zynqmp_firmware_remove()
error: dereferencing freed memory 'feature_data'

Use hash_for_each_safe for safe removal of hash entry.

Fixes: acfdd18591ea ("firmware: xilinx: Use hash-table for api feature check")
Reported-by: kernel test robot <[email protected]>
Reported-by: Dan Carpenter <[email protected]>
Signed-off-by: Tejas Patel <[email protected]>
Signed-off-by: Rajan Vaja <[email protected]>
---
drivers/firmware/xilinx/zynqmp.c | 5 +++--
1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/drivers/firmware/xilinx/zynqmp.c b/drivers/firmware/xilinx/zynqmp.c
index 7eb9958..83082e2 100644
--- a/drivers/firmware/xilinx/zynqmp.c
+++ b/drivers/firmware/xilinx/zynqmp.c
@@ -2,7 +2,7 @@
/*
* Xilinx Zynq MPSoC Firmware layer
*
- * Copyright (C) 2014-2020 Xilinx, Inc.
+ * Copyright (C) 2014-2021 Xilinx, Inc.
*
* Michal Simek <[email protected]>
* Davorin Mista <[email protected]>
@@ -1280,12 +1280,13 @@ static int zynqmp_firmware_probe(struct platform_device *pdev)
static int zynqmp_firmware_remove(struct platform_device *pdev)
{
struct pm_api_feature_data *feature_data;
+ struct hlist_node *tmp;
int i;

mfd_remove_devices(&pdev->dev);
zynqmp_pm_api_debugfs_exit();

- hash_for_each(pm_api_features_map, i, feature_data, hentry) {
+ hash_for_each_safe(pm_api_features_map, i, tmp, feature_data, hentry) {
hash_del(&feature_data->hentry);
kfree(feature_data);
}
--
2.7.4

2021-02-12 14:16:12

by Michal Simek

Subject: Re: [PATCH] drivers: firmware: xilinx: Fix dereferencing freed memory

On 2/8/21 7:31 AM, Rajan Vaja wrote:
> From: Tejas Patel <[email protected]>
>
> Fix smatch warning:
> drivers/firmware/xilinx/zynqmp.c:1288 zynqmp_firmware_remove()
> error: dereferencing freed memory 'feature_data'
>
> Use hash_for_each_safe for safe removal of hash entry.
>
> Fixes: acfdd18591ea ("firmware: xilinx: Use hash-table for api feature check")
> Reported-by: kernel test robot <[email protected]>
> Reported-by: Dan Carpenter <[email protected]>
> Signed-off-by: Tejas Patel <[email protected]>
> Signed-off-by: Rajan Vaja <[email protected]>
> ---
> drivers/firmware/xilinx/zynqmp.c | 5 +++--
> 1 file changed, 3 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/firmware/xilinx/zynqmp.c b/drivers/firmware/xilinx/zynqmp.c
> index 7eb9958..83082e2 100644
> --- a/drivers/firmware/xilinx/zynqmp.c
> +++ b/drivers/firmware/xilinx/zynqmp.c
> @@ -2,7 +2,7 @@
> /*
> * Xilinx Zynq MPSoC Firmware layer
> *
> - * Copyright (C) 2014-2020 Xilinx, Inc.
> + * Copyright (C) 2014-2021 Xilinx, Inc.
> *
> * Michal Simek <[email protected]>
> * Davorin Mista <[email protected]>
> @@ -1280,12 +1280,13 @@ static int zynqmp_firmware_probe(struct platform_device *pdev)
> static int zynqmp_firmware_remove(struct platform_device *pdev)
> {
> struct pm_api_feature_data *feature_data;
> + struct hlist_node *tmp;
> int i;
>
> mfd_remove_devices(&pdev->dev);
> zynqmp_pm_api_debugfs_exit();
>
> - hash_for_each(pm_api_features_map, i, feature_data, hentry) {
> + hash_for_each_safe(pm_api_features_map, i, tmp, feature_data, hentry) {
> hash_del(&feature_data->hentry);
> kfree(feature_data);
> }
>

Applied.

Thanks,
Michal