Am Donnerstag, den 22.08.2019, 07:28 -0700 schrieb syzbot: > Hello, > > syzbot found the following crash on: > > HEAD commit: eea39f24 usb-fuzzer: main usb gadget fuzzer driver > git tree: https://github.com/google/kasan.git usb-fuzzer > console output: https://syzkaller.appspot.com/x/log.txt?x=163ae012600000 > kernel config: https://syzkaller.appspot.com/x/.config?x=d0c62209eedfd54e > dashboard link: https://syzkaller.appspot.com/bug?extid=80899a8a8efe8968cde7 > compiler: gcc (GCC) 9.0.0 20181231 (experimental) > syz repro: https://syzkaller.appspot.com/x/repro.syz?x=1739cb0e600000 > C reproducer: https://syzkaller.appspot.com/x/repro.c?x=154fcc2e600000 > > IMPORTANT: if you fix the bug, please add the following tag to the commit: > Reported-by: syzbot+80899a8a8efe8968c...@syzkaller.appspotmail.com
#syz test: https://github.com/google/kasan.git eea39f24 >From 4f21b5aabc448719aa612b9359d90a178cb485d8 Mon Sep 17 00:00:00 2001 From: Oliver Neukum <oneu...@suse.com> Date: Thu, 22 Aug 2019 16:37:33 +0200 Subject: [PATCH] rtl8712: fix race between firmware failing to load and disconnect We have to wait for the attempt to load the firmware to finish before we evaluate the result. Reported-by: syzbot+80899a8a8efe8968c...@syzkaller.appspotmail.com Signed-off-by: Oliver Neukum <oneu...@suse.com> --- drivers/staging/rtl8712/hal_init.c | 3 ++- drivers/staging/rtl8712/usb_intf.c | 8 ++++++-- 2 files changed, 8 insertions(+), 3 deletions(-) diff --git a/drivers/staging/rtl8712/hal_init.c b/drivers/staging/rtl8712/hal_init.c index 40145c0338e4..42c0a3c947f1 100644 --- a/drivers/staging/rtl8712/hal_init.c +++ b/drivers/staging/rtl8712/hal_init.c @@ -33,7 +33,6 @@ static void rtl871x_load_fw_cb(const struct firmware *firmware, void *context) { struct _adapter *adapter = context; - complete(&adapter->rtl8712_fw_ready); if (!firmware) { struct usb_device *udev = adapter->dvobjpriv.pusbdev; struct usb_interface *usb_intf = adapter->pusb_intf; @@ -41,11 +40,13 @@ static void rtl871x_load_fw_cb(const struct firmware *firmware, void *context) dev_err(&udev->dev, "r8712u: Firmware request failed\n"); usb_put_dev(udev); usb_set_intfdata(usb_intf, NULL); + complete(&adapter->rtl8712_fw_ready); return; } adapter->fw = firmware; /* firmware available - start netdev */ register_netdev(adapter->pnetdev); + complete(&adapter->rtl8712_fw_ready); } static const char firmware_file[] = "rtlwifi/rtl8712u.bin"; diff --git a/drivers/staging/rtl8712/usb_intf.c b/drivers/staging/rtl8712/usb_intf.c index d0daae0b8299..8d7b57073592 100644 --- a/drivers/staging/rtl8712/usb_intf.c +++ b/drivers/staging/rtl8712/usb_intf.c @@ -595,10 +595,13 @@ static void r871xu_dev_remove(struct usb_interface *pusb_intf) if (pnetdev) { struct _adapter *padapter = netdev_priv(pnetdev); - usb_set_intfdata(pusb_intf, NULL); - release_firmware(padapter->fw); /* never exit with a firmware callback pending */ wait_for_completion(&padapter->rtl8712_fw_ready); + pnetdev = usb_get_intfdata(pusb_intf); + usb_set_intfdata(pusb_intf, NULL); + if (!pnetdev) + goto raced_with_firmware_failure; + release_firmware(padapter->fw); if (drvpriv.drv_registered) padapter->surprise_removed = true; unregister_netdev(pnetdev); /* will call netdev_close() */ @@ -609,6 +612,7 @@ static void r871xu_dev_remove(struct usb_interface *pusb_intf) r871x_dev_unload(padapter); r8712_free_drv_sw(padapter); +raced_with_firmware_failure: /* decrease the reference count of the usb device structure * when disconnect */ -- 2.16.4
