[PATCH 5.11 122/601] firmware: xilinx: Fix dereferencing freed memory

Greg Kroah-Hartman
2021-05-12T17:02:24Z

From: Tejas Patel <tejas.patel@xilinx.com>

[ Upstream commit f1f21bece82c76a56a96988ec7d51ccc033d8949 ]

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 <lkp@intel.com>
Reported-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Tejas Patel <tejas.patel@xilinx.com>
Signed-off-by: Rajan Vaja <rajan.vaja@xilinx.com>
Link: https://lore.kernel.org/r/1612765883-22018-1-git-send-email-rajan.vaja@xilinx.com
Signed-off-by: Michal Simek <michal.simek@xilinx.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
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 7eb9958662dd..83082e2f2e44 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 <michal.simek@xilinx.com>
* Davorin Mista <davorin.mista@aggios.com>
@@ -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);
}
--
2.30.2