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@163.com Cc: stable@vger.kernel.org --- drivers/net/wireless/broadcom/brcm80211/brcmfmac/cfg80211.c | 3 +++ 1 file changed, 3 insertions(+)
diff --git a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/cfg80211.c b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/cfg80211.c index 667462369a32..0224e377eb6e 100644 --- a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/cfg80211.c +++ b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/cfg80211.c @@ -8431,6 +8431,9 @@ void brcmf_cfg80211_detach(struct brcmf_cfg80211_info *cfg) if (!cfg) return;
+ if (timer_pending(&cfg->escan_timeout)) + del_timer_sync(&cfg->escan_timeout); + cancel_delayed_work_sync(&cfg->escan_timeout_work); brcmf_pno_detach(cfg); brcmf_btcoex_detach(cfg); wiphy_unregister(cfg->wiphy);
Hi Zheng,
kernel test robot noticed the following build errors:
[auto build test ERROR on wireless-next/main] [also build test ERROR on wireless/main linus/master v6.6 next-20231103] [If your patch is applied to the wrong git tree, kindly drop us a note. And when submitting patch, we suggest to use '--base' as documented in https://git-scm.com/docs/git-format-patch#_base_tree_information]
url: https://github.com/intel-lab-lkp/linux/commits/Zheng-Wang/wifi-cfg80211-Fix-... base: https://git.kernel.org/pub/scm/linux/kernel/git/wireless/wireless-next.git main patch link: https://lore.kernel.org/r/20231104054709.716585-1-zyytlz.wz%40163.com patch subject: [PATCH] wifi: cfg80211: Fix use-after-free bug in brcmf_cfg80211_detach config: arc-randconfig-002-20231104 (https://download.01.org/0day-ci/archive/20231104/202311041735.pCIzwiLF-lkp@i...) compiler: arceb-elf-gcc (GCC) 13.2.0 reproduce (this is a W=1 build): (https://download.01.org/0day-ci/archive/20231104/202311041735.pCIzwiLF-lkp@i...)
If you fix the issue in a separate patch/commit (i.e. not just a new version of the same patch/commit), kindly add following tags | Reported-by: kernel test robot lkp@intel.com | Closes: https://lore.kernel.org/oe-kbuild-all/202311041735.pCIzwiLF-lkp@intel.com/
All errors (new ones prefixed by >>):
drivers/net/wireless/broadcom/brcm80211/brcmfmac/cfg80211.c: In function 'brcmf_cfg80211_detach':
drivers/net/wireless/broadcom/brcm80211/brcmfmac/cfg80211.c:8436:34: error: passing argument 1 of 'cancel_delayed_work_sync' from incompatible pointer type [-Werror=incompatible-pointer-types]
8436 | cancel_delayed_work_sync(&cfg->escan_timeout_work); | ^~~~~~~~~~~~~~~~~~~~~~~~ | | | struct work_struct * In file included from include/linux/mm_types.h:19, from include/linux/mmzone.h:22, from include/linux/gfp.h:7, from include/linux/xarray.h:15, from include/linux/list_lru.h:14, from include/linux/fs.h:13, from include/linux/highmem.h:5, from include/linux/bvec.h:10, from include/linux/skbuff.h:17, from include/linux/if_ether.h:19, from include/linux/etherdevice.h:20, from drivers/net/wireless/broadcom/brcm80211/brcmfmac/cfg80211.c:9: include/linux/workqueue.h:511:59: note: expected 'struct delayed_work *' but argument is of type 'struct work_struct *' 511 | extern bool cancel_delayed_work_sync(struct delayed_work *dwork); | ~~~~~~~~~~~~~~~~~~~~~^~~~~ cc1: some warnings being treated as errors
vim +/cancel_delayed_work_sync +8436 drivers/net/wireless/broadcom/brcm80211/brcmfmac/cfg80211.c
8428 8429 void brcmf_cfg80211_detach(struct brcmf_cfg80211_info *cfg) 8430 { 8431 if (!cfg) 8432 return; 8433 8434 if (timer_pending(&cfg->escan_timeout)) 8435 del_timer_sync(&cfg->escan_timeout);
8436 cancel_delayed_work_sync(&cfg->escan_timeout_work);
linux-stable-mirror@lists.linaro.org
-
Johannes Berg -
kernel test robot -
Zheng Wang