[PATCH] iwlwifi: Fix memory leak on reduce_power_data buffer

[PATCH] iwlwifi: Fix memory leak on reduce_power_data buffer

[Colin King]

From: Colin Ian King <colin.king@canonical.com>

In the error case where the TLV length is invalid the allocated
reduce_power_data buffer pointer is set to ERR_PTR(-EINVAL) without
first kfree'ing any previous allocated memory. Fix this memory
leak by kfree'ing it before taking the error return path.

Addresses-Coverity: ("Resource leak")
Fixes: 9dad325f9d57 ("iwlwifi: support loading the reduced power table from UEFI")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
---
 drivers/net/wireless/intel/iwlwifi/fw/uefi.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/drivers/net/wireless/intel/iwlwifi/fw/uefi.c b/drivers/net/wireless/intel/iwlwifi/fw/uefi.c
index a7c79d814aa4..413bfb2ae54d 100644
--- a/drivers/net/wireless/intel/iwlwifi/fw/uefi.c
+++ b/drivers/net/wireless/intel/iwlwifi/fw/uefi.c
@@ -86,6 +86,7 @@ static void *iwl_uefi_reduce_power_section(struct iwl_trans *trans,
 		if (len < tlv_len) {
 			IWL_ERR(trans, "invalid TLV len: %zd/%u\n",
 				len, tlv_len);
+			kfree(reduce_power_data);
 			reduce_power_data = ERR_PTR(-EINVAL);
 			goto out;
 		}
-- 
2.31.1

Re: [PATCH] iwlwifi: Fix memory leak on reduce_power_data buffer

[Dan Carpenter]

On Fri, Jul 23, 2021 at 03:11:52PM +0100, Colin King wrote:
> From: Colin Ian King <colin.king@canonical.com>
> 
> In the error case where the TLV length is invalid the allocated
> reduce_power_data buffer pointer is set to ERR_PTR(-EINVAL) without
> first kfree'ing any previous allocated memory. Fix this memory
> leak by kfree'ing it before taking the error return path.
> 
> Addresses-Coverity: ("Resource leak")
> Fixes: 9dad325f9d57 ("iwlwifi: support loading the reduced power table from UEFI")
> Signed-off-by: Colin Ian King <colin.king@canonical.com>
> ---
>  drivers/net/wireless/intel/iwlwifi/fw/uefi.c | 1 +
>  1 file changed, 1 insertion(+)
> 
> diff --git a/drivers/net/wireless/intel/iwlwifi/fw/uefi.c b/drivers/net/wireless/intel/iwlwifi/fw/uefi.c
> index a7c79d814aa4..413bfb2ae54d 100644
> --- a/drivers/net/wireless/intel/iwlwifi/fw/uefi.c
> +++ b/drivers/net/wireless/intel/iwlwifi/fw/uefi.c
> @@ -86,6 +86,7 @@ static void *iwl_uefi_reduce_power_section(struct iwl_trans *trans,
>  		if (len < tlv_len) {
                    ^^^^^^^^^^^^^
Not related to your patch but probably this comparison aught to be done
against aligned tlv_len.

		tlv_len = ALIGN(tlv_len, 4);
		if (len < tlv_len) {

Especially in the iwl_uefi_reduce_power_parse() function.  Or maybe just
if (tlv_len % 0x4 || len < tlv_len)?

regards,
dan carpenter