Zheng Wang <zyytlz.wz@xxxxxxx> writes: > 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: e756af5b30b0 ("brcmfmac: add e-scan support.") > Signed-off-by: Zheng Wang <zyytlz.wz@xxxxxxx> > Cc: stable@xxxxxxxxxxxxxxx > --- > v5: > - replace del_timer_sync with timer_shutdown_sync suggested by > Arend and Takashi > v4: > - rename the subject and add CVE number as Ping-Ke Shih suggested > v3: > - rename the subject as Johannes suggested > v2: > - fix the error of kernel test bot reported > --- > drivers/net/wireless/broadcom/brcm80211/brcmfmac/cfg80211.c | 2 ++ > 1 file changed, 2 insertions(+) > > diff --git a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/cfg80211.c b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/cfg80211.c > index 667462369a32..a8723a61c9e4 100644 > --- a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/cfg80211.c > +++ b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/cfg80211.c > @@ -8431,6 +8431,8 @@ void brcmf_cfg80211_detach(struct brcmf_cfg80211_info *cfg) > if (!cfg) > return; > > + timer_shutdown_sync(&cfg->escan_timeout); > + cancel_work_sync(&cfg->escan_timeout_work); > brcmf_pno_detach(cfg); > brcmf_btcoex_detach(cfg); > wiphy_unregister(cfg->wiphy); Has anyone tested this on a real device? As v1 didn't even compile I am very cautious: https://patchwork.kernel.org/project/linux-wireless/patch/20231104054709.716585-1-zyytlz.wz@xxxxxxx/ -- https://patchwork.kernel.org/project/linux-wireless/list/ https://wireless.wiki.kernel.org/en/developers/documentation/submittingpatches
