Re: [PATCH for-4.15] brcmfmac: change driver unbind order of the sdio function devices

[Kalle Valo]

Arend van Spriel  writes:

> In the function brcmf_sdio_firmware_callback() the driver is
> unbound from the sdio function devices in the error path.
> However, the order in which it is done resulted in a use-after-free
> issue (see brcmf_ops_sdio_remove() in bcmsdh.c). Hence change
> the order and first unbind sdio function #2 device and then
> unbind sdio function #1 device.
>
> Cc: sta...@vger.kernel.org # v4.12.x
> Fixes: 7a51461fc2da ("brcmfmac: unbind all devices upon failure in firmware 
> callback")
> Reported-by: Stefan Wahren 
> Reviewed-by: Hante Meuleman 
> Reviewed-by: Pieter-Paul Giesberts 
> Reviewed-by: Franky Lin 
> Signed-off-by: Arend van Spriel 

I'll queue this for v4.15.

-- 
Kalle Valo

[PATCH for-4.15] brcmfmac: change driver unbind order of the sdio function devices

[Arend van Spriel]

In the function brcmf_sdio_firmware_callback() the driver is
unbound from the sdio function devices in the error path.
However, the order in which it is done resulted in a use-after-free
issue (see brcmf_ops_sdio_remove() in bcmsdh.c). Hence change
the order and first unbind sdio function #2 device and then
unbind sdio function #1 device.

Cc: sta...@vger.kernel.org # v4.12.x
Fixes: 7a51461fc2da ("brcmfmac: unbind all devices upon failure in firmware 
callback")
Reported-by: Stefan Wahren 
Reviewed-by: Hante Meuleman 
Reviewed-by: Pieter-Paul Giesberts 
Reviewed-by: Franky Lin 
Signed-off-by: Arend van Spriel 
---
 drivers/net/wireless/broadcom/brcm80211/brcmfmac/sdio.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/sdio.c 
b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/sdio.c
index e3495ea..3108f7ee 100644
--- a/drivers/net/wireless/broadcom/brcm80211/brcmfmac/sdio.c
+++ b/drivers/net/wireless/broadcom/brcm80211/brcmfmac/sdio.c
@@ -4121,8 +4121,8 @@ static void brcmf_sdio_firmware_callback(struct device 
*dev, int err,
sdio_release_host(sdiodev->func[1]);
 fail:
brcmf_dbg(TRACE, "failed: dev=%s, err=%d\n", dev_name(dev), err);
-   device_release_driver(dev);
device_release_driver(&sdiodev->func[2]->dev);
+   device_release_driver(dev);
 }
 
 struct brcmf_sdio *brcmf_sdio_probe(struct brcmf_sdio_dev *sdiodev)
-- 
1.9.1