brcmfmac: change driver unbind order of the sdio function devices

Arend Van Spriel · Kalle Valo · commit 5c3de777bdaf · 2017-12-02T17:22:47.000+02:00
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: stable@vger.kernel.org # v4.12.x Fixes: 7a51461 ("brcmfmac: unbind all devices upon failure in firmware callback") Reported-by: Stefan Wahren <stefan.wahren@i2se.com> Reviewed-by: Hante Meuleman <hante.meuleman@broadcom.com> Reviewed-by: Pieter-Paul Giesberts <pieter-paul.giesberts@broadcom.com> Reviewed-by: Franky Lin <franky.lin@broadcom.com> Signed-off-by: Arend van Spriel <arend.vanspriel@broadcom.com> Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
diff --git 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)

Original file line number	Diff line number	Diff line change
`@@ -4121,8 +4121,8 @@ static void brcmf_sdio_firmware_callback(struct device *dev, int err,`
`4121`	`4121`	`sdio_release_host(sdiodev->func[1]);`
`4122`	`4122`	`fail:`
`4123`	`4123`	`brcmf_dbg(TRACE, "failed: dev=%s, err=%d\n", dev_name(dev), err);`
`4124`		`- device_release_driver(dev);`
`4125`	`4124`	`device_release_driver(&sdiodev->func[2]->dev);`
	`4125`	`+ device_release_driver(dev);`
`4126`	`4126`	`}`
`4127`	`4127`
`4128`	`4128`	`struct brcmf_sdio brcmf_sdio_probe(struct brcmf_sdio_dev sdiodev)`