[PATCH 4.9 12/31] rt2x00usb: fix anchor initialization

Greg Kroah-Hartman
2017-04-16T08:18:23Z

From: Stanislaw Gruszka <sgruszka@redhat.com>

commit 0488a6121dfe6cbd44de15ea3627913b7549a1e9 upstream.

If device fail to initialize we can OOPS in rt2x00lib_remove_dev(), due
to using uninitialized usb_anchor structure:

[ 855.435820] ieee80211 phy3: rt2x00usb_vendor_request: Error - Vendor Request 0x07 failed for offset 0x1000 with error -19
[ 855.435826] ieee80211 phy3: rt2800_probe_rt: Error - Invalid RT chipset 0x0000, rev 0000 detected
[ 855.435829] ieee80211 phy3: rt2x00lib_probe_dev: Error - Failed to allocate device
[ 855.435845] BUG: unable to handle kernel NULL pointer dereference at 0000000000000028
[ 855.435900] IP: _raw_spin_lock_irq+0xd/0x30
[ 855.435926] PGD 0
[ 855.435953] Oops: 0002 [#1] SMP
<snip>
[ 855.437011] Call Trace:
[ 855.437029] ? usb_kill_anchored_urbs+0x27/0xc0
[ 855.437061] rt2x00lib_remove_dev+0x190/0x1c0 [rt2x00lib]
[ 855.437097] rt2x00lib_probe_dev+0x246/0x7a0 [rt2x00lib]
[ 855.437149] ? ieee80211_roc_setup+0x9e/0xd0 [mac80211]
[ 855.437183] ? __kmalloc+0x1af/0x1f0
[ 855.437207] ? rt2x00usb_probe+0x13d/0xc50 [rt2x00usb]
[ 855.437240] rt2x00usb_probe+0x155/0xc50 [rt2x00usb]
[ 855.437273] rt2800usb_probe+0x15/0x20 [rt2800usb]
[ 855.437304] usb_probe_interface+0x159/0x2d0
[ 855.437333] driver_probe_device+0x2bb/0x460

Patch changes initialization sequence to fix the problem.

Cc: Vishal Thanki <vishalthanki@gmail.com>
Fixes: 8b4c0009313f ("rt2x00usb: Use usb anchor to manage URB")
Signed-off-by: Stanislaw Gruszka <sgruszka@redhat.com>
Signed-off-by: Kalle Valo <kvalo@codeaurora.org>
Cc: Signed-off-by: Amit Pundir <amit.pundir@linaro.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
drivers/net/wireless/ralink/rt2x00/rt2x00usb.c | 13 ++++++++-----
1 file changed, 8 insertions(+), 5 deletions(-)

--- a/drivers/net/wireless/ralink/rt2x00/rt2x00usb.c
+++ b/drivers/net/wireless/ralink/rt2x00/rt2x00usb.c
@@ -824,10 +824,6 @@ int rt2x00usb_probe(struct usb_interface
if (retval)
goto exit_free_device;

- retval = rt2x00lib_probe_dev(rt2x00dev);
- if (retval)
- goto exit_free_reg;
-
rt2x00dev->anchor = devm_kmalloc(&usb_dev->dev,
sizeof(struct usb_anchor),
GFP_KERNEL);
@@ -835,10 +831,17 @@ int rt2x00usb_probe(struct usb_interface
retval = -ENOMEM;
goto exit_free_reg;
}
-
init_usb_anchor(rt2x00dev->anchor);
+
+ retval = rt2x00lib_probe_dev(rt2x00dev);
+ if (retval)
+ goto exit_free_anchor;
+
return 0;

+exit_free_anchor:
+ usb_kill_anchored_urbs(rt2x00dev->anchor);
+
exit_free_reg:
rt2x00usb_free_reg(rt2x00dev);