This is a note to let you know that I've just added the patch titled wifi: wfx: fix memory leak when starting AP to the 6.6-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: wifi-wfx-fix-memory-leak-when-starting-ap.patch and it can be found in the queue-6.6 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. commit b8c83575a81c7856873f592d50448592754fd42a Author: Jérôme Pouiller <jerome.pouiller@xxxxxxxxxx> Date: Fri Feb 2 17:42:13 2024 +0100 wifi: wfx: fix memory leak when starting AP [ Upstream commit b8cfb7c819dd39965136a66fe3a7fde688d976fc ] Kmemleak reported this error: unreferenced object 0xd73d1180 (size 184): comm "wpa_supplicant", pid 1559, jiffies 13006305 (age 964.245s) hex dump (first 32 bytes): 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ 00 00 00 00 00 00 00 00 1e 00 01 00 00 00 00 00 ................ backtrace: [<5ca11420>] kmem_cache_alloc+0x20c/0x5ac [<127bdd74>] __alloc_skb+0x144/0x170 [<fb8a5e38>] __netdev_alloc_skb+0x50/0x180 [<0f9fa1d5>] __ieee80211_beacon_get+0x290/0x4d4 [mac80211] [<7accd02d>] ieee80211_beacon_get_tim+0x54/0x18c [mac80211] [<41e25cc3>] wfx_start_ap+0xc8/0x234 [wfx] [<93a70356>] ieee80211_start_ap+0x404/0x6b4 [mac80211] [<a4a661cd>] nl80211_start_ap+0x76c/0x9e0 [cfg80211] [<47bd8b68>] genl_rcv_msg+0x198/0x378 [<453ef796>] netlink_rcv_skb+0xd0/0x130 [<6b7c977a>] genl_rcv+0x34/0x44 [<66b2d04d>] netlink_unicast+0x1b4/0x258 [<f965b9b6>] netlink_sendmsg+0x1e8/0x428 [<aadb8231>] ____sys_sendmsg+0x1e0/0x274 [<d2b5212d>] ___sys_sendmsg+0x80/0xb4 [<69954f45>] __sys_sendmsg+0x64/0xa8 unreferenced object 0xce087000 (size 1024): comm "wpa_supplicant", pid 1559, jiffies 13006305 (age 964.246s) hex dump (first 32 bytes): 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 ................ 10 00 07 40 00 00 00 00 00 00 00 00 00 00 00 00 ...@............ backtrace: [<9a993714>] __kmalloc_track_caller+0x230/0x600 [<f83ea192>] kmalloc_reserve.constprop.0+0x30/0x74 [<a2c61343>] __alloc_skb+0xa0/0x170 [<fb8a5e38>] __netdev_alloc_skb+0x50/0x180 [<0f9fa1d5>] __ieee80211_beacon_get+0x290/0x4d4 [mac80211] [<7accd02d>] ieee80211_beacon_get_tim+0x54/0x18c [mac80211] [<41e25cc3>] wfx_start_ap+0xc8/0x234 [wfx] [<93a70356>] ieee80211_start_ap+0x404/0x6b4 [mac80211] [<a4a661cd>] nl80211_start_ap+0x76c/0x9e0 [cfg80211] [<47bd8b68>] genl_rcv_msg+0x198/0x378 [<453ef796>] netlink_rcv_skb+0xd0/0x130 [<6b7c977a>] genl_rcv+0x34/0x44 [<66b2d04d>] netlink_unicast+0x1b4/0x258 [<f965b9b6>] netlink_sendmsg+0x1e8/0x428 [<aadb8231>] ____sys_sendmsg+0x1e0/0x274 [<d2b5212d>] ___sys_sendmsg+0x80/0xb4 However, since the kernel is build optimized, it seems the stack is not accurate. It appears the issue is related to wfx_set_mfp_ap(). The issue is obvious in this function: memory allocated by ieee80211_beacon_get() is never released. Fixing this leak makes kmemleak happy. Reported-by: Ulrich Mohr <u.mohr@xxxxxxxxxxxxxxxx> Co-developed-by: Ulrich Mohr <u.mohr@xxxxxxxxxxxxxxxx> Signed-off-by: Ulrich Mohr <u.mohr@xxxxxxxxxxxxxxxx> Fixes: 268bceec1684 ("staging: wfx: fix BA when device is AP and MFP is enabled") Signed-off-by: Jérôme Pouiller <jerome.pouiller@xxxxxxxxxx> Signed-off-by: Kalle Valo <kvalo@xxxxxxxxxx> Link: https://msgid.link/20240202164213.1606145-1-jerome.pouiller@xxxxxxxxxx Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> diff --git a/drivers/net/wireless/silabs/wfx/sta.c b/drivers/net/wireless/silabs/wfx/sta.c index 073e870b26415..871667650dbef 100644 --- a/drivers/net/wireless/silabs/wfx/sta.c +++ b/drivers/net/wireless/silabs/wfx/sta.c @@ -362,6 +362,7 @@ static int wfx_set_mfp_ap(struct wfx_vif *wvif) const int pairwise_cipher_suite_count_offset = 8 / sizeof(u16); const int pairwise_cipher_suite_size = 4 / sizeof(u16); const int akm_suite_size = 4 / sizeof(u16); + int ret = -EINVAL; const u16 *ptr; if (unlikely(!skb)) @@ -370,22 +371,26 @@ static int wfx_set_mfp_ap(struct wfx_vif *wvif) ptr = (u16 *)cfg80211_find_ie(WLAN_EID_RSN, skb->data + ieoffset, skb->len - ieoffset); if (unlikely(!ptr)) - return -EINVAL; + goto free_skb; ptr += pairwise_cipher_suite_count_offset; if (WARN_ON(ptr > (u16 *)skb_tail_pointer(skb))) - return -EINVAL; + goto free_skb; ptr += 1 + pairwise_cipher_suite_size * *ptr; if (WARN_ON(ptr > (u16 *)skb_tail_pointer(skb))) - return -EINVAL; + goto free_skb; ptr += 1 + akm_suite_size * *ptr; if (WARN_ON(ptr > (u16 *)skb_tail_pointer(skb))) - return -EINVAL; + goto free_skb; wfx_hif_set_mfp(wvif, *ptr & BIT(7), *ptr & BIT(6)); - return 0; + ret = 0; + +free_skb: + dev_kfree_skb(skb); + return ret; } int wfx_start_ap(struct ieee80211_hw *hw, struct ieee80211_vif *vif,