Commit cc4069fb authored by Zheng Wang's avatar Zheng Wang Committed by Zhengchao Shao
Browse files

wifi: brcmfmac: Fix use-after-free bug in brcmf_cfg80211_detach 

stable inclusion
from stable-v5.10.215
commit bacb8c3ab86dcd760c15903fcee58169bc3026aa
category: bugfix
bugzilla: https://gitee.com/src-openeuler/kernel/issues/I8DQ75
CVE: CVE-2023-47233

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=bacb8c3ab86dcd760c15903fcee58169bc3026aa

--------------------------------

[ Upstream commit 0f7352557a35ab7888bc7831411ec8a3cbe20d78 ]

This is the candidate patch of CVE-2023-47233 :
https://nvd.nist.gov/vuln/detail/CVE-2023-47233



In brcm80211 driver,it starts with the following invoking chain
to start init a timeout worker:

->brcmf_usb_probe
  ->brcmf_usb_probe_cb
    ->brcmf_attach
      ->brcmf_bus_started
        ->brcmf_cfg80211_attach
          ->wl_init_priv
            ->brcmf_init_escan
              ->INIT_WORK(&cfg->escan_timeout_work,
		  brcmf_cfg80211_escan_timeout_worker);

If we disconnect the USB by hotplug, it will call
brcmf_usb_disconnect to make cleanup. The invoking chain is :

brcmf_usb_disconnect
  ->brcmf_usb_disconnect_cb
    ->brcmf_detach
      ->brcmf_cfg80211_detach
        ->kfree(cfg);

While the timeout woker may still be running. This will cause
a use-after-free bug on cfg in brcmf_cfg80211_escan_timeout_worker.

Fix it by deleting the timer and canceling the worker in
brcmf_cfg80211_detach.

Fixes: e756af5b ("brcmfmac: add e-scan support.")
Signed-off-by: default avatarZheng Wang <zyytlz.wz@163.com>
Cc: stable@vger.kernel.org
[arend.vanspriel@broadcom.com: keep timer delete as is and cancel work just before free]
Signed-off-by: default avatarArend van Spriel <arend.vanspriel@broadcom.com>
Signed-off-by: default avatarKalle Valo <kvalo@kernel.org>
Link: https://msgid.link/20240107072504.392713-1-arend.vanspriel@broadcom.com


Signed-off-by: default avatarSasha Levin <sashal@kernel.org>
Signed-off-by: default avatarZhengchao Shao <shaozhengchao@huawei.com>
parent 96786530

drivers/net/wireless/broadcom/brcm80211/brcmfmac/cfg80211.c

+2 −2
Original line number Diff line number Diff line
@@ -790,8 +790,7 @@ s32 brcmf_notify_escan_complete(struct brcmf_cfg80211_info *cfg, 
	scan_request = cfg->scan_request;

	cfg->scan_request = NULL;



	if (timer_pending(&cfg->escan_timeout))

		del_timer_sync(&cfg->escan_timeout);

	timer_delete_sync(&cfg->escan_timeout);



	if (fw_abort) {

		/* Do a scan abort to stop the driver's scan engine */
@@ -7674,6 +7673,7 @@ void brcmf_cfg80211_detach(struct brcmf_cfg80211_info *cfg) 
	brcmf_btcoex_detach(cfg);

	wiphy_unregister(cfg->wiphy);

	wl_deinit_priv(cfg);

	cancel_work_sync(&cfg->escan_timeout_work);

	brcmf_free_wiphy(cfg->wiphy);

	kfree(cfg);

}