From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 A72443FF1AD; Fri, 15 May 2026 16:04:35 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=10.30.226.201 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1778861075; cv=none; b=n7AgNqtrLFi8IogKYcwNwJAbeNo7SHbH1YQyLqRParA9wM6AAsptk3PArF7Pdzx8tfaBzNYEFNuttCbqqUuDnXec1qkOnE4BwO/HRcoA/1L/km0YB0weVdTIeLOeD26LA/JjTRzbJdhJoUyei1QGh0gHmq1QdwOC8l9FEyQncDE= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1778861075; c=relaxed/simple; bh=jka79jmJbC4PAIdq9GlIAZvwVNlVNr0IBmghTcV82k0=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=ki+EUNEsh9laA9dv+c2S1MRBp+jTnYiQOZxuDHdlPwSBkru4aEM1M9T1a8w2h1TVtjEY77gRbW6fTMODkmSfXvPC1ZWc8oc4hBc8d++Tdfz+cB9wsRXxI9cov7X0UABZzznkMiXZvqal2sWrLjo/ac5Z+Gcvfmms2A/CpvKMbQk= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=Vh2+LlgG; arc=none smtp.client-ip=10.30.226.201 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="Vh2+LlgG" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 3C710C2BCB0; Fri, 15 May 2026 16:04:35 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1778861075; bh=jka79jmJbC4PAIdq9GlIAZvwVNlVNr0IBmghTcV82k0=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=Vh2+LlgG0UtaN/A1mMHULtDsiqArtMLeF4rtOMF+Ki6RKY8vdR9CWeBr59Htto4Cj vbXvri3Xvz61RlTtNFw8E9ZJzTxVCNKUBSPrszBAY+fPpiL1mC6pWI7sl2Q5odOLy+ RcoMZ8z6LNt/+pO2L9JaDuTQSqACRSkNngzQV4rY= 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 6.6 188/474] wifi: rsi: fix kthread lifetime race between self-exit and external-stop Date: Fri, 15 May 2026 17:44:57 +0200 Message-ID: <20260515154719.088728917@linuxfoundation.org> X-Mailer: git-send-email 2.54.0 In-Reply-To: <20260515154715.053014143@linuxfoundation.org> References: <20260515154715.053014143@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore Precedence: bulk X-Mailing-List: stable@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.6-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);