[PATCH v3 6.6.y] wifi: cfg80211: release locks on error in cfg80211_wext_siwgenie()

[Wentao Guan]

This error path returns while both wiphy_lock() and wdev_lock() are still
held, so one malformed IE request can permanently block later operations
on this wiphy. Route the error through out to release both locks.

This bug is stable-specific: it was introduced by the stable backport
commit d01f1600e8b0 ("wifi: cfg80211: validate IEs in
cfg80211_wext_siwgenie()") of upstream
commit a2f5286ca4f3 ("wifi: cfg80211: validate IEs in
cfg80211_wext_siwgenie()").  Upstream is safe because that function
runs under guard(wiphy)(), added by
commit f42d22d3f7963 ("wifi: cfg80211: define and use wiphy guard"),
while this tree still uses explicit locking and the separate wdev
mutex that upstream removed in
commit 076fc8775dafe ("wifi: cfg80211: remove wdev mutex").  Backporting
those locking reworks is not appropriate as a minimal stable fix.

This is a fix for stable v6.6.158 backport commit, so no upstream commit.

Reported-by: Harshit Mogalapalli <harshit.m.mogalapalli@xxxxxxxxxx>
Closes: https://lore.kernel.org/all/93db0eae-f479-4343-a126-59987ae0dc22@xxxxxxxxxx/
Fixes: d01f1600e8b0 ("wifi: cfg80211: validate IEs in cfg80211_wext_siwgenie()")
Signed-off-by: Wentao Guan <guanwentao@xxxxxxxxxxxxx>
---
changelog v3:
update message as greg suggested.
changelog v2:
add reported by.
---
---
 net/wireless/wext-sme.c | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/net/wireless/wext-sme.c b/net/wireless/wext-sme.c
index cfa903eb0e82f..0e7c314bdeef0 100644
--- a/net/wireless/wext-sme.c
+++ b/net/wireless/wext-sme.c
@@ -354,8 +354,10 @@ int cfg80211_wext_siwgenie(struct net_device *dev,
 			/* nothing */
 		}
 
-		if (!for_each_element_completed(elem, extra, ie_len))
-			return -EINVAL;
+		if (!for_each_element_completed(elem, extra, ie_len)) {
+			err = -EINVAL;
+			goto out;
+		}
 
 		ie = kmemdup(extra, ie_len, GFP_KERNEL);
 		if (!ie) {
-- 
2.39.5