diff options
| author | Pavel Skripkin <paskripkin@gmail.com> | 2021-10-20 00:17:18 +0300 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2021-10-20 19:35:38 +0200 |
| commit | c052cc1a069c3e575619cf64ec427eb41176ca70 (patch) | |
| tree | a9cd01001ad7225b593870538e57056f87d78beb /drivers/staging/rtl8712 | |
| parent | 5978d492f04746d2cbf486c62dc466f43e60805f (diff) | |
| download | linux-c052cc1a069c3e575619cf64ec427eb41176ca70.tar.bz2 | |
staging: rtl8712: fix use-after-free in rtl8712_dl_fw
Syzbot reported use-after-free in rtl8712_dl_fw(). The problem was in
race condition between r871xu_dev_remove() ->ndo_open() callback.
It's easy to see from crash log, that driver accesses released firmware
in ->ndo_open() callback. It may happen, since driver was releasing
firmware _before_ unregistering netdev. Fix it by moving
unregister_netdev() before cleaning up resources.
Call Trace:
...
rtl871x_open_fw drivers/staging/rtl8712/hal_init.c:83 [inline]
rtl8712_dl_fw+0xd95/0xe10 drivers/staging/rtl8712/hal_init.c:170
rtl8712_hal_init drivers/staging/rtl8712/hal_init.c:330 [inline]
rtl871x_hal_init+0xae/0x180 drivers/staging/rtl8712/hal_init.c:394
netdev_open+0xe6/0x6c0 drivers/staging/rtl8712/os_intfs.c:380
__dev_open+0x2bc/0x4d0 net/core/dev.c:1484
Freed by task 1306:
...
release_firmware+0x1b/0x30 drivers/base/firmware_loader/main.c:1053
r871xu_dev_remove+0xcc/0x2c0 drivers/staging/rtl8712/usb_intf.c:599
usb_unbind_interface+0x1d8/0x8d0 drivers/usb/core/driver.c:458
Fixes: 8c213fa59199 ("staging: r8712u: Use asynchronous firmware loading")
Cc: stable <stable@vger.kernel.org>
Reported-and-tested-by: syzbot+c55162be492189fb4f51@syzkaller.appspotmail.com
Signed-off-by: Pavel Skripkin <paskripkin@gmail.com>
Link: https://lore.kernel.org/r/20211019211718.26354-1-paskripkin@gmail.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/staging/rtl8712')
| -rw-r--r-- | drivers/staging/rtl8712/usb_intf.c | 4 |
1 files changed, 2 insertions, 2 deletions
diff --git a/drivers/staging/rtl8712/usb_intf.c b/drivers/staging/rtl8712/usb_intf.c index 17e705411e64..ee4c61f85a07 100644 --- a/drivers/staging/rtl8712/usb_intf.c +++ b/drivers/staging/rtl8712/usb_intf.c @@ -595,12 +595,12 @@ static void r871xu_dev_remove(struct usb_interface *pusb_intf) /* never exit with a firmware callback pending */ wait_for_completion(&padapter->rtl8712_fw_ready); + if (pnetdev->reg_state != NETREG_UNINITIALIZED) + unregister_netdev(pnetdev); /* will call netdev_close() */ usb_set_intfdata(pusb_intf, NULL); release_firmware(padapter->fw); if (drvpriv.drv_registered) padapter->surprise_removed = true; - if (pnetdev->reg_state != NETREG_UNINITIALIZED) - unregister_netdev(pnetdev); /* will call netdev_close() */ r8712_flush_rwctrl_works(padapter); r8712_flush_led_works(padapter); udelay(1); |