Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input

[net-next-2.6.git] / net / wireless / wext-core.c

diff --git a/net/wireless/wext-core.c b/net/wireless/wext-core.c
index 0ef17bc42bac05996eab6e2dada02fc67953c3dc..8f5116f5af19988555316eb5b97c7465a0890677 100644 (file)
--- a/net/wireless/wext-core.c
+++ b/net/wireless/wext-core.c
@@ -782,6 +782,22 @@ static int ioctl_standard_iw_point(struct iw_point *iwp, unsigned int cmd,
                }
        }
 
+       if (IW_IS_GET(cmd) && !(descr->flags & IW_DESCR_FLAG_NOMAX)) {
+               /*
+                * If this is a GET, but not NOMAX, it means that the extra
+                * data is not bounded by userspace, but by max_tokens. Thus
+                * set the length to max_tokens. This matches the extra data
+                * allocation.
+                * The driver should fill it with the number of tokens it
+                * provided, and it may check iwp->length rather than having
+                * knowledge of max_tokens. If the driver doesn't change the
+                * iwp->length, this ioctl just copies back max_token tokens
+                * filled with zeroes. Hopefully the driver isn't claiming
+                * them to be valid data.
+                */
+               iwp->length = descr->max_tokens;
+       }
+
        err = handler(dev, info, (union iwreq_data *) iwp, extra);
 
        iwp->length += essid_compat;