[PATCH v2] wifi: rtlwifi: rtl8192du: Fix possible memory leak in rtl92du_init_sw_vars()

[PATCH v2] wifi: rtlwifi: rtl8192du: Fix possible memory leak in rtl92du_init_sw_vars()

[Abdun Nihaal]

The memory allocated inside rtl92du_init_shared_data() is not freed in
any of the subsequent error paths in rtl92du_init_sw_vars().
Fix that by adding a call to rtl92du_deinit_shared_data() in the error
path.

Fixes: b5dc8873b6ff ("wifi: rtlwifi: Add rtl8192du/sw.c")
Cc: stable@vger.kernel.org
Signed-off-by: Abdun Nihaal <nihaal@cse.iitm.ac.in>
---
Compile tested only. Issue found using static analysis.

v1->v2:
- Avoid jumping to error path when rtl92du_init_shared_data() fails,
  since in that error path, the memory is already freed even on error.
  Thanks to Ping-Ke Shih for pointing this out.

v1 link: https://patchwork.kernel.org/project/linux-wireless/patch/20260722121236.136754-1-nihaal@cse.iitm.ac.in/

 drivers/net/wireless/realtek/rtlwifi/rtl8192du/sw.c | 12 +++++++++---
 1 file changed, 9 insertions(+), 3 deletions(-)

diff --git a/drivers/net/wireless/realtek/rtlwifi/rtl8192du/sw.c b/drivers/net/wireless/realtek/rtlwifi/rtl8192du/sw.c
index 7bafb051d5ec..88e8cc590c54 100644
--- a/drivers/net/wireless/realtek/rtlwifi/rtl8192du/sw.c
+++ b/drivers/net/wireless/realtek/rtlwifi/rtl8192du/sw.c
@@ -145,8 +145,10 @@ static int rtl92du_init_sw_vars(struct ieee80211_hw *hw)
 
 	/* for firmware buf */
 	rtlpriv->rtlhal.pfirmware = kmalloc(0x8000, GFP_KERNEL);
-	if (!rtlpriv->rtlhal.pfirmware)
-		return -ENOMEM;
+	if (!rtlpriv->rtlhal.pfirmware) {
+		err = -ENOMEM;
+		goto error;
+	}
 
 	rtlpriv->max_fw_size = 0x8000;
 	pr_info("Driver for Realtek RTL8192DU WLAN interface\n");
@@ -160,10 +162,14 @@ static int rtl92du_init_sw_vars(struct ieee80211_hw *hw)
 		pr_err("Failed to request firmware!\n");
 		kfree(rtlpriv->rtlhal.pfirmware);
 		rtlpriv->rtlhal.pfirmware = NULL;
-		return err;
+		goto error;
 	}
 
 	return 0;
+
+error:
+	rtl92du_deinit_shared_data(hw);
+	return err;
 }
 
 static void rtl92du_deinit_sw_vars(struct ieee80211_hw *hw)
-- 
2.43.0

RE: [PATCH v2] wifi: rtlwifi: rtl8192du: Fix possible memory leak in rtl92du_init_sw_vars()

[Ping-Ke Shih]

Abdun Nihaal <nihaal@cse.iitm.ac.in> wrote:
> The memory allocated inside rtl92du_init_shared_data() is not freed in
> any of the subsequent error paths in rtl92du_init_sw_vars().
> Fix that by adding a call to rtl92du_deinit_shared_data() in the error
> path.
> 
> Fixes: b5dc8873b6ff ("wifi: rtlwifi: Add rtl8192du/sw.c")
> Cc: stable@vger.kernel.org
> Signed-off-by: Abdun Nihaal <nihaal@cse.iitm.ac.in>

Acked-by: Ping-Ke Shih <pkshih@realtek.com>