[PATCH] wifi: iwlegacy: unregister the LED if 3945 hardware registration fails

[PATCH] wifi: iwlegacy: unregister the LED if 3945 hardware registration fails

[Zhao Li]

If ieee80211_register_hw() fails during 3945 setup, later LED callbacks
can access hardware and driver state that probe has already freed.

il3945_setup_mac() registers the LED before the mac80211 hardware, but
its registration error path does not call il_leds_exit(). The analogous
4965 failure releases the driver and reaches its existing remove cleanup.

Unregister the 3945 LED before unwinding a failed hardware registration.

LLM assistance was used to find the bug and review.

Fixes: 5ed540aecc2a ("iwlwifi: use mac80211 throughput trigger")
Cc: stable@vger.kernel.org
Signed-off-by: Zhao Li <enderaoelyther@gmail.com>
---
Validation: A W=1 module build with MODPOST passed. Not
reproduced; 3945 hardware was unavailable.
Sparse C=2 passed. Targeted Smatch introduced no new diagnostics.

 drivers/net/wireless/intel/iwlegacy/3945-mac.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/drivers/net/wireless/intel/iwlegacy/3945-mac.c b/drivers/net/wireless/intel/iwlegacy/3945-mac.c
index f7ca182d1494..5e11f0597255 100644
--- a/drivers/net/wireless/intel/iwlegacy/3945-mac.c
+++ b/drivers/net/wireless/intel/iwlegacy/3945-mac.c
@@ -3529,6 +3529,7 @@ il3945_setup_mac(struct il_priv *il)
 	ret = ieee80211_register_hw(il->hw);
 	if (ret) {
 		IL_ERR("Failed to register hw (error %d)\n", ret);
+		il_leds_exit(il);
 		return ret;
 	}
 	il->mac80211_registered = 1;

base-commit: 25e73f1d6868c759c8eb56cad4e411692c5341b4
-- 
2.56.0