From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 8E272261B9E; Sat, 30 May 2026 17:52:28 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1780163549; cv=none; b=WOJ7UmPd+UajG8Zf0iEtzvnFsNezG2fxfDdrheiJP1lujX8cKNSMyxthu2EgKuN3nO595/wE5fb2pkRftYCJ8CexJKbk/vCqWt94tJPTGOlq6zjGKi65Zt29JyI6JGGZVB0/z9WWF6stniKMog6aS4i026+WLNdODrEqHhqSNU0= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1780163549; c=relaxed/simple; bh=mHpoQuVlR7AdGTq3RK/sUDCRZIZmhd2zfdnfdegPkAU=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=WqzUeS0FfEY+ar2mheyTdKltkKyoGK5tdiusX5MG0VRGTKydOqcAz3TT9EcQ6FYuzQOz0uY84gFuuw+y94BgvBITfYe4cSrdZlndvEf9Uq+SE3nruBfqFB21awkdNOsQxgoqul4d9XPNexozFmRqIpzmMaEku+OZG8biJcGJsgI= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=g8fLWWPl; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="g8fLWWPl" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 90A331F00893; Sat, 30 May 2026 17:52:27 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1780163548; bh=H1V5DVMpNyl/YS8sGasu/OCbxLIov8gxIaymW8kjnf4=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=g8fLWWPlDbKgujYLNkGbrgSPiiLKRKSDAfRjgBWx9z7YtuTK3L4+lFwRdZUJSC5p9 //oCPbuxdpb/9VahQnhVNU/6QmkSCNFEyqeINue+CJ3cEwUYtlEkMry4UPiNJIoxSX V0hXZnHeLyVBq7iy9zFASPemXioa0tiTnpevBKmE= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, syzbot+5de83f57cd8531f55596@syzkaller.appspotmail.com, Jeongjun Park , Johannes Berg Subject: [PATCH 5.15 290/776] wifi: rsi: fix kthread lifetime race between self-exit and external-stop Date: Sat, 30 May 2026 18:00:04 +0200 Message-ID: <20260530160248.054915624@linuxfoundation.org> X-Mailer: git-send-email 2.53.0 In-Reply-To: <20260530160240.228940103@linuxfoundation.org> References: <20260530160240.228940103@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 5.15-stable review patch. If anyone has any objections, please let me know. ------------------ From: Jeongjun Park commit db57a1aa54ff68669781976e4edb045e09e2b65b upstream. RSI driver use both self-exit(kthread_complete_and_exit) and external-stop (kthread_stop) when killing a kthread. Generally, kthread_stop() is called first, and in this case, no particular issues occur. However, in rare instances where kthread_complete_and_exit() is called first and then kthread_stop() is called, a UAF occurs because the kthread object, which has already exited and been freed, is accessed again. Therefore, to prevent this with minimal modification, you must remove kthread_stop() and change the code to wait until the self-exit operation is completed. Cc: Reported-by: syzbot+5de83f57cd8531f55596@syzkaller.appspotmail.com Closes: https://lore.kernel.org/all/69e5d03b.a00a0220.1bd0ca.0064.GAE@google.com/ Fixes: 4c62764d0fc2 ("rsi: improve kernel thread handling to fix kernel panic") Signed-off-by: Jeongjun Park Link: https://patch.msgid.link/20260422173846.37640-1-aha310510@gmail.com Signed-off-by: Johannes Berg Signed-off-by: Greg Kroah-Hartman --- drivers/net/wireless/rsi/rsi_common.h | 5 ++--- 1 file changed, 2 insertions(+), 3 deletions(-) --- a/drivers/net/wireless/rsi/rsi_common.h +++ b/drivers/net/wireless/rsi/rsi_common.h @@ -70,12 +70,11 @@ static inline int rsi_create_kthread(str return 0; } -static inline int rsi_kill_thread(struct rsi_thread *handle) +static inline void rsi_kill_thread(struct rsi_thread *handle) { atomic_inc(&handle->thread_done); rsi_set_event(&handle->event); - - return kthread_stop(handle->task); + wait_for_completion(&handle->completion); } void rsi_mac80211_detach(struct rsi_hw *hw);