Re: [PATCH] wifi: wfx: fix memory leak when starting AP

[Kalle Valo]

Jérôme Pouiller <jerome.pouiller@xxxxxxxxxx> wrote:

> 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>

Patch applied to wireless-next.git, thanks.

b8cfb7c819dd wifi: wfx: fix memory leak when starting AP

-- 
https://patchwork.kernel.org/project/linux-wireless/patch/20240202164213.1606145-1-jerome.pouiller@xxxxxxxxxx/

https://wireless.wiki.kernel.org/en/developers/documentation/submittingpatches