[PATCH 4.4 073/118] Revert "wext: Fix 32 bit iwpriv compatibility issue with 64 bit Kernel"

From: Greg Kroah-Hartman
Date: Thu Sep 22 2016 - 15:04:27 EST


4.4-stable review patch. If anyone has any objections, please let me know.

------------------

From: Johannes Berg <johannes.berg@xxxxxxxxx>

commit 4d0bd46a4d55383f7b925e6cf7865a77e0f0e020 upstream.

This reverts commit 3d5fdff46c4b2b9534fa2f9fc78e90a48e0ff724.

Ben Hutchings pointed out that the commit isn't safe since it assumes
that the structure used by the driver is iw_point, when in fact there's
no way to know about that.

Fortunately, the only driver in the tree that ever runs this code path
is the wilc1000 staging driver, so it doesn't really matter.

Clearly I should have investigated this better before applying, sorry.

Reported-by: Ben Hutchings <ben@xxxxxxxxxxxxxxx>
Fixes: 3d5fdff46c4b ("wext: Fix 32 bit iwpriv compatibility issue with 64 bit Kernel")
Signed-off-by: Johannes Berg <johannes.berg@xxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
net/wireless/wext-core.c | 25 ++-----------------------
1 file changed, 2 insertions(+), 23 deletions(-)

--- a/net/wireless/wext-core.c
+++ b/net/wireless/wext-core.c
@@ -955,29 +955,8 @@ static int wireless_process_ioctl(struct
return private(dev, iwr, cmd, info, handler);
}
/* Old driver API : call driver ioctl handler */
- if (dev->netdev_ops->ndo_do_ioctl) {
-#ifdef CONFIG_COMPAT
- if (info->flags & IW_REQUEST_FLAG_COMPAT) {
- int ret = 0;
- struct iwreq iwr_lcl;
- struct compat_iw_point *iwp_compat = (void *) &iwr->u.data;
-
- memcpy(&iwr_lcl, iwr, sizeof(struct iwreq));
- iwr_lcl.u.data.pointer = compat_ptr(iwp_compat->pointer);
- iwr_lcl.u.data.length = iwp_compat->length;
- iwr_lcl.u.data.flags = iwp_compat->flags;
-
- ret = dev->netdev_ops->ndo_do_ioctl(dev, (void *) &iwr_lcl, cmd);
-
- iwp_compat->pointer = ptr_to_compat(iwr_lcl.u.data.pointer);
- iwp_compat->length = iwr_lcl.u.data.length;
- iwp_compat->flags = iwr_lcl.u.data.flags;
-
- return ret;
- } else
-#endif
- return dev->netdev_ops->ndo_do_ioctl(dev, ifr, cmd);
- }
+ if (dev->netdev_ops->ndo_do_ioctl)
+ return dev->netdev_ops->ndo_do_ioctl(dev, ifr, cmd);
return -EOPNOTSUPP;
}