[PATCH v2] wifi: ath11k: fix memory leaks in beacon template setup

[PATCH v2] wifi: ath11k: fix memory leaks in beacon template setup

[Zilin Guan]

The functions ath11k_mac_setup_bcn_tmpl_ema() and
ath11k_mac_setup_bcn_tmpl_mbssid() allocate memory for beacon templates
but fail to free it when parameter setup returns an error.

Since beacon templates must be released during normal execution, they
must also be released in the error handling paths to prevent memory
leaks.

Fix this by adding the missing deallocation calls in the respective
error paths.

Compile tested only. Issue found using a prototype static analysis tool
and code review.

Fixes: 3a415daa3e8b ("wifi: ath11k: add P2P IE in beacon template")
Fixes: 335a92765d30 ("wifi: ath11k: MBSSID beacon support")
Suggested-by: Baochen Qiang <baochen.qiang@oss.qualcomm.com>
Signed-off-by: Zilin Guan <zilin@seu.edu.cn>
---
Changes in v2:
- Use unified exit paths for cleanup.

 drivers/net/wireless/ath/ath11k/mac.c | 25 +++++++++++++++----------
 1 file changed, 15 insertions(+), 10 deletions(-)

diff --git a/drivers/net/wireless/ath/ath11k/mac.c b/drivers/net/wireless/ath/ath11k/mac.c
index 4dfd08b58416..42edcc5e9e49 100644
--- a/drivers/net/wireless/ath/ath11k/mac.c
+++ b/drivers/net/wireless/ath/ath11k/mac.c
@@ -1561,8 +1561,10 @@ static int ath11k_mac_setup_bcn_tmpl_ema(struct ath11k_vif *arvif,
 	}
 
 	if (tx_arvif == arvif) {
-		if (ath11k_mac_set_vif_params(tx_arvif, beacons->bcn[0].skb))
-			return -EINVAL;
+		if (ath11k_mac_set_vif_params(tx_arvif, beacons->bcn[0].skb)) {
+			ret = -EINVAL;
+			goto free;
+		}
 	} else {
 		arvif->wpaie_present = tx_arvif->wpaie_present;
 	}
@@ -1589,11 +1591,11 @@ static int ath11k_mac_setup_bcn_tmpl_ema(struct ath11k_vif *arvif,
 		}
 	}
 
-	ieee80211_beacon_free_ema_list(beacons);
-
 	if (tx_arvif != arvif && !nontx_vif_params_set)
-		return -EINVAL; /* Profile not found in the beacons */
+		ret = -EINVAL; /* Profile not found in the beacons */
 
+free:
+	ieee80211_beacon_free_ema_list(beacons);
 	return ret;
 }
 
@@ -1622,19 +1624,22 @@ static int ath11k_mac_setup_bcn_tmpl_mbssid(struct ath11k_vif *arvif,
 	}
 
 	if (tx_arvif == arvif) {
-		if (ath11k_mac_set_vif_params(tx_arvif, bcn))
-			return -EINVAL;
+		if (ath11k_mac_set_vif_params(tx_arvif, bcn)) {
+			ret = -EINVAL;
+			goto free;
+		}
 	} else if (!ath11k_mac_set_nontx_vif_params(tx_arvif, arvif, bcn)) {
-		return -EINVAL;
+		ret = -EINVAL;
+		goto free;
 	}
 
 	ret = ath11k_wmi_bcn_tmpl(ar, arvif->vdev_id, &offs, bcn, 0);
-	kfree_skb(bcn);
-
 	if (ret)
 		ath11k_warn(ab, "failed to submit beacon template command: %d\n",
 			    ret);
 
+free:
+	kfree_skb(bcn);
 	return ret;
 }
 
-- 
2.34.1

Re: [PATCH v2] wifi: ath11k: fix memory leaks in beacon template setup

[Baochen Qiang]

On 1/20/2026 2:37 PM, Zilin Guan wrote:
> The functions ath11k_mac_setup_bcn_tmpl_ema() and
> ath11k_mac_setup_bcn_tmpl_mbssid() allocate memory for beacon templates
> but fail to free it when parameter setup returns an error.
> 
> Since beacon templates must be released during normal execution, they
> must also be released in the error handling paths to prevent memory
> leaks.
> 
> Fix this by adding the missing deallocation calls in the respective
> error paths.
> 
> Compile tested only. Issue found using a prototype static analysis tool
> and code review.
> 
> Fixes: 3a415daa3e8b ("wifi: ath11k: add P2P IE in beacon template")
> Fixes: 335a92765d30 ("wifi: ath11k: MBSSID beacon support")
> Suggested-by: Baochen Qiang <baochen.qiang@oss.qualcomm.com>
> Signed-off-by: Zilin Guan <zilin@seu.edu.cn>
> ---
> Changes in v2:
> - Use unified exit paths for cleanup.
> 
>  drivers/net/wireless/ath/ath11k/mac.c | 25 +++++++++++++++----------
>  1 file changed, 15 insertions(+), 10 deletions(-)
> 
> diff --git a/drivers/net/wireless/ath/ath11k/mac.c b/drivers/net/wireless/ath/ath11k/mac.c
> index 4dfd08b58416..42edcc5e9e49 100644
> --- a/drivers/net/wireless/ath/ath11k/mac.c
> +++ b/drivers/net/wireless/ath/ath11k/mac.c
> @@ -1561,8 +1561,10 @@ static int ath11k_mac_setup_bcn_tmpl_ema(struct ath11k_vif *arvif,
>  	}
>  
>  	if (tx_arvif == arvif) {
> -		if (ath11k_mac_set_vif_params(tx_arvif, beacons->bcn[0].skb))
> -			return -EINVAL;
> +		if (ath11k_mac_set_vif_params(tx_arvif, beacons->bcn[0].skb)) {
> +			ret = -EINVAL;
> +			goto free;
> +		}
>  	} else {
>  		arvif->wpaie_present = tx_arvif->wpaie_present;
>  	}
> @@ -1589,11 +1591,11 @@ static int ath11k_mac_setup_bcn_tmpl_ema(struct ath11k_vif *arvif,
>  		}
>  	}
>  
> -	ieee80211_beacon_free_ema_list(beacons);
> -
>  	if (tx_arvif != arvif && !nontx_vif_params_set)
> -		return -EINVAL; /* Profile not found in the beacons */
> +		ret = -EINVAL; /* Profile not found in the beacons */
>  
> +free:
> +	ieee80211_beacon_free_ema_list(beacons);
>  	return ret;
>  }
>  
> @@ -1622,19 +1624,22 @@ static int ath11k_mac_setup_bcn_tmpl_mbssid(struct ath11k_vif *arvif,
>  	}
>  
>  	if (tx_arvif == arvif) {
> -		if (ath11k_mac_set_vif_params(tx_arvif, bcn))
> -			return -EINVAL;
> +		if (ath11k_mac_set_vif_params(tx_arvif, bcn)) {
> +			ret = -EINVAL;
> +			goto free;
> +		}
>  	} else if (!ath11k_mac_set_nontx_vif_params(tx_arvif, arvif, bcn)) {
> -		return -EINVAL;
> +		ret = -EINVAL;
> +		goto free;
>  	}
>  
>  	ret = ath11k_wmi_bcn_tmpl(ar, arvif->vdev_id, &offs, bcn, 0);
> -	kfree_skb(bcn);
> -
>  	if (ret)
>  		ath11k_warn(ab, "failed to submit beacon template command: %d\n",
>  			    ret);
>  
> +free:
> +	kfree_skb(bcn);
>  	return ret;
>  }
>  

Reviewed-by: Baochen Qiang <baochen.qiang@oss.qualcomm.com>

Re: [PATCH v2] wifi: ath11k: fix memory leaks in beacon template setup

[Jeff Johnson]

On 1/19/2026 10:37 PM, Zilin Guan wrote:
> The functions ath11k_mac_setup_bcn_tmpl_ema() and
> ath11k_mac_setup_bcn_tmpl_mbssid() allocate memory for beacon templates
> but fail to free it when parameter setup returns an error.
> 
> Since beacon templates must be released during normal execution, they
> must also be released in the error handling paths to prevent memory
> leaks.
> 
> Fix this by adding the missing deallocation calls in the respective
> error paths.
> 
> Compile tested only. Issue found using a prototype static analysis tool
> and code review.
> 
> Fixes: 3a415daa3e8b ("wifi: ath11k: add P2P IE in beacon template")
> Fixes: 335a92765d30 ("wifi: ath11k: MBSSID beacon support")
> Suggested-by: Baochen Qiang <baochen.qiang@oss.qualcomm.com>
> Signed-off-by: Zilin Guan <zilin@seu.edu.cn>
> ---
> Changes in v2:
> - Use unified exit paths for cleanup.
> 
>  drivers/net/wireless/ath/ath11k/mac.c | 25 +++++++++++++++----------
>  1 file changed, 15 insertions(+), 10 deletions(-)
> 
> diff --git a/drivers/net/wireless/ath/ath11k/mac.c b/drivers/net/wireless/ath/ath11k/mac.c
> index 4dfd08b58416..42edcc5e9e49 100644
> --- a/drivers/net/wireless/ath/ath11k/mac.c
> +++ b/drivers/net/wireless/ath/ath11k/mac.c
> @@ -1561,8 +1561,10 @@ static int ath11k_mac_setup_bcn_tmpl_ema(struct ath11k_vif *arvif,

while looking to apply this patch I noticed the following logic earlier in the
function:

 	beacons = ieee80211_beacon_get_template_ema_list(tx_arvif->ar->hw,
 							 tx_arvif->vif, 0);
 	if (!beacons || !beacons->cnt) {
 		ath11k_warn(arvif->ar->ab,
 			    "failed to get ema beacon templates from mac80211\n");
 		return -EPERM;
 	}

I did not look at ieee80211_beacon_get_template_ema_list()
But if it is possible that this can return a valid beacons pointer with
beacons->cnt == 0, then won't this also leak the beacons allocation?

Given that ieee80211_beacon_free_ema_list(beacons) can handle a NULL
beacons pointer, perhaps this should also goto free?

>  	}
>  
>  	if (tx_arvif == arvif) {
> -		if (ath11k_mac_set_vif_params(tx_arvif, beacons->bcn[0].skb))
> -			return -EINVAL;
> +		if (ath11k_mac_set_vif_params(tx_arvif, beacons->bcn[0].skb)) {
> +			ret = -EINVAL;
> +			goto free;
> +		}
>  	} else {
>  		arvif->wpaie_present = tx_arvif->wpaie_present;
>  	}
> @@ -1589,11 +1591,11 @@ static int ath11k_mac_setup_bcn_tmpl_ema(struct ath11k_vif *arvif,
>  		}
>  	}
>  
> -	ieee80211_beacon_free_ema_list(beacons);
> -
>  	if (tx_arvif != arvif && !nontx_vif_params_set)
> -		return -EINVAL; /* Profile not found in the beacons */
> +		ret = -EINVAL; /* Profile not found in the beacons */
>  
> +free:
> +	ieee80211_beacon_free_ema_list(beacons);
>  	return ret;
>  }
>  
> @@ -1622,19 +1624,22 @@ static int ath11k_mac_setup_bcn_tmpl_mbssid(struct ath11k_vif *arvif,
>  	}
>  
>  	if (tx_arvif == arvif) {
> -		if (ath11k_mac_set_vif_params(tx_arvif, bcn))
> -			return -EINVAL;
> +		if (ath11k_mac_set_vif_params(tx_arvif, bcn)) {
> +			ret = -EINVAL;
> +			goto free;
> +		}
>  	} else if (!ath11k_mac_set_nontx_vif_params(tx_arvif, arvif, bcn)) {
> -		return -EINVAL;
> +		ret = -EINVAL;
> +		goto free;
>  	}
>  
>  	ret = ath11k_wmi_bcn_tmpl(ar, arvif->vdev_id, &offs, bcn, 0);
> -	kfree_skb(bcn);
> -
>  	if (ret)
>  		ath11k_warn(ab, "failed to submit beacon template command: %d\n",
>  			    ret);
>  
> +free:
> +	kfree_skb(bcn);
>  	return ret;
>  }
>  

Re: [PATCH v2] wifi: ath11k: fix memory leaks in beacon template setup

[Zilin Guan]

On Wed, Jan 28, 2026 at 08:30:22AM -0800, Jeff Johnson wrote:
> On 1/19/2026 10:37 PM, Zilin Guan wrote:
> > The functions ath11k_mac_setup_bcn_tmpl_ema() and
> > ath11k_mac_setup_bcn_tmpl_mbssid() allocate memory for beacon templates
> > but fail to free it when parameter setup returns an error.
> > 
> > Since beacon templates must be released during normal execution, they
> > must also be released in the error handling paths to prevent memory
> > leaks.
> > 
> > Fix this by adding the missing deallocation calls in the respective
> > error paths.
> > 
> > Compile tested only. Issue found using a prototype static analysis tool
> > and code review.
> > 
> > Fixes: 3a415daa3e8b ("wifi: ath11k: add P2P IE in beacon template")
> > Fixes: 335a92765d30 ("wifi: ath11k: MBSSID beacon support")
> > Suggested-by: Baochen Qiang <baochen.qiang@oss.qualcomm.com>
> > Signed-off-by: Zilin Guan <zilin@seu.edu.cn>
> > ---
> > Changes in v2:
> > - Use unified exit paths for cleanup.
> > 
> >  drivers/net/wireless/ath/ath11k/mac.c | 25 +++++++++++++++----------
> >  1 file changed, 15 insertions(+), 10 deletions(-)
> > 
> > diff --git a/drivers/net/wireless/ath/ath11k/mac.c b/drivers/net/wireless/ath/ath11k/mac.c
> > index 4dfd08b58416..42edcc5e9e49 100644
> > --- a/drivers/net/wireless/ath/ath11k/mac.c
> > +++ b/drivers/net/wireless/ath/ath11k/mac.c
> > @@ -1561,8 +1561,10 @@ static int ath11k_mac_setup_bcn_tmpl_ema(struct ath11k_vif *arvif,
> 
> while looking to apply this patch I noticed the following logic earlier in the
> function:
> 
>  	beacons = ieee80211_beacon_get_template_ema_list(tx_arvif->ar->hw,
>  							 tx_arvif->vif, 0);
>  	if (!beacons || !beacons->cnt) {
>  		ath11k_warn(arvif->ar->ab,
>  			    "failed to get ema beacon templates from mac80211\n");
>  		return -EPERM;
>  	}
> 
> I did not look at ieee80211_beacon_get_template_ema_list()
> But if it is possible that this can return a valid beacons pointer with
> beacons->cnt == 0, then won't this also leak the beacons allocation?
> 
> Given that ieee80211_beacon_free_ema_list(beacons) can handle a NULL
> beacons pointer, perhaps this should also goto free?

Hi Jeff,

Thanks for pointing that out.

I looked into the allocation chain for 
ieee80211_beacon_get_template_ema_list():

ieee80211_beacon_get_template_ema_list()
	|__ __ieee80211_beacon_get()
		|__ ieee80211_beacon_get_ap_ema_list()

It seems that ieee80211_beacon_get_ap_ema_list() only returns a valid 
pointer when ema->cnt is non-zero. Therefore, a valid beacons pointer with 
beacons->cnt == 0 is likely unreachable under the current mac80211 
implementation, making the existing check more of a defensive programming
measure.

However, for the sake of strict logical consistency, it would make sense 
to use the goto path there as well.

Do you think it's worth updating this in a v3, or is the current v2 
sufficient given the current call logic?

Best regards, 
Zilin

Re: [PATCH v2] wifi: ath11k: fix memory leaks in beacon template setup

[Jeff Johnson]

On 1/28/2026 10:13 PM, Zilin Guan wrote:
> On Wed, Jan 28, 2026 at 08:30:22AM -0800, Jeff Johnson wrote:
>> On 1/19/2026 10:37 PM, Zilin Guan wrote:
>>> The functions ath11k_mac_setup_bcn_tmpl_ema() and
>>> ath11k_mac_setup_bcn_tmpl_mbssid() allocate memory for beacon templates
>>> but fail to free it when parameter setup returns an error.
>>>
>>> Since beacon templates must be released during normal execution, they
>>> must also be released in the error handling paths to prevent memory
>>> leaks.
>>>
>>> Fix this by adding the missing deallocation calls in the respective
>>> error paths.
>>>
>>> Compile tested only. Issue found using a prototype static analysis tool
>>> and code review.
>>>
>>> Fixes: 3a415daa3e8b ("wifi: ath11k: add P2P IE in beacon template")
>>> Fixes: 335a92765d30 ("wifi: ath11k: MBSSID beacon support")
>>> Suggested-by: Baochen Qiang <baochen.qiang@oss.qualcomm.com>
>>> Signed-off-by: Zilin Guan <zilin@seu.edu.cn>
>>> ---
>>> Changes in v2:
>>> - Use unified exit paths for cleanup.
>>>
>>>  drivers/net/wireless/ath/ath11k/mac.c | 25 +++++++++++++++----------
>>>  1 file changed, 15 insertions(+), 10 deletions(-)
>>>
>>> diff --git a/drivers/net/wireless/ath/ath11k/mac.c b/drivers/net/wireless/ath/ath11k/mac.c
>>> index 4dfd08b58416..42edcc5e9e49 100644
>>> --- a/drivers/net/wireless/ath/ath11k/mac.c
>>> +++ b/drivers/net/wireless/ath/ath11k/mac.c
>>> @@ -1561,8 +1561,10 @@ static int ath11k_mac_setup_bcn_tmpl_ema(struct ath11k_vif *arvif,
>>
>> while looking to apply this patch I noticed the following logic earlier in the
>> function:
>>
>>  	beacons = ieee80211_beacon_get_template_ema_list(tx_arvif->ar->hw,
>>  							 tx_arvif->vif, 0);
>>  	if (!beacons || !beacons->cnt) {
>>  		ath11k_warn(arvif->ar->ab,
>>  			    "failed to get ema beacon templates from mac80211\n");
>>  		return -EPERM;
>>  	}
>>
>> I did not look at ieee80211_beacon_get_template_ema_list()
>> But if it is possible that this can return a valid beacons pointer with
>> beacons->cnt == 0, then won't this also leak the beacons allocation?
>>
>> Given that ieee80211_beacon_free_ema_list(beacons) can handle a NULL
>> beacons pointer, perhaps this should also goto free?
> 
> Hi Jeff,
> 
> Thanks for pointing that out.
> 
> I looked into the allocation chain for 
> ieee80211_beacon_get_template_ema_list():
> 
> ieee80211_beacon_get_template_ema_list()
> 	|__ __ieee80211_beacon_get()
> 		|__ ieee80211_beacon_get_ap_ema_list()
> 
> It seems that ieee80211_beacon_get_ap_ema_list() only returns a valid 
> pointer when ema->cnt is non-zero. Therefore, a valid beacons pointer with 
> beacons->cnt == 0 is likely unreachable under the current mac80211 
> implementation, making the existing check more of a defensive programming
> measure.
> 
> However, for the sake of strict logical consistency, it would make sense 
> to use the goto path there as well.
> 
> Do you think it's worth updating this in a v3, or is the current v2 
> sufficient given the current call logic?

I prefer strict logical consistency so I prefer either adding the goto or
removing the beacons->cnt check.

Or a completely different approach would be to use cleanup.h functionality and
annotate beacons with __free(ieee80211_beacon_free_ema_list) so that no
explicit calls to that function are required. If you try this approach then
beacons must be defined at the point of allocation:

	struct ieee80211_ema_beacons *beacons __free(ieee80211_beacon_free_ema_list) =
		ieee80211_beacon_get_template_ema_list(tx_arvif->ar->hw,
						       tx_arvif->vif, 0);

Note that I have not tried this approach with allocations other than from the
kmalloc() family with __free(kfree), but in theory this should work.

/jeff

Re: [PATCH v2] wifi: ath11k: fix memory leaks in beacon template setup

[Zilin Guan]

On Thu, Jan 29, 2026 at 07:36:43AM -0800, Jeff Johnson wrote:
> I prefer strict logical consistency so I prefer either adding the goto or
> removing the beacons->cnt check.
> 
> Or a completely different approach would be to use cleanup.h functionality and
> annotate beacons with __free(ieee80211_beacon_free_ema_list) so that no
> explicit calls to that function are required. If you try this approach then
> beacons must be defined at the point of allocation:
> 
> 	struct ieee80211_ema_beacons *beacons __free(ieee80211_beacon_free_ema_list) =
> 		ieee80211_beacon_get_template_ema_list(tx_arvif->ar->hw,
> 						       tx_arvif->vif, 0);
> 
> Note that I have not tried this approach with allocations other than from the
> kmalloc() family with __free(kfree), but in theory this should work.
> 
> /jeff

Thanks! I'll add the goto path for the beacons->cnt check in v3.

Best regards,
Zilin