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 1BD151C03 for ; Mon, 20 Mar 2023 15:09:19 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id 8FC42C4339B; Mon, 20 Mar 2023 15:09:18 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1679324958; bh=rEzDGNZMJOr22C/pfGJunXDJWsvBlZz/NIE1o+SClOY=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=rSGrce44sxGSziMcJWV4JKk7QODY5yoM9JPz8sPn6DSB2FhtGsxjBvS80NJwCR2Rs pyni9ZkhaYrbMAQqBFRTwxO+nDfap8sbe3zXC9tGsZX26YrwfNP4IRlCp/28F3nOZj w7cXpQpvhZliaY/yPlgm/+x/1RmSXrXobJNuAKvw= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Zheng Wang , Krzysztof Kozlowski , Jakub Kicinski , Sasha Levin Subject: [PATCH 5.15 033/115] nfc: st-nci: Fix use after free bug in ndlc_remove due to race condition Date: Mon, 20 Mar 2023 15:54:05 +0100 Message-Id: <20230320145450.839788742@linuxfoundation.org> X-Mailer: git-send-email 2.40.0 In-Reply-To: <20230320145449.336983711@linuxfoundation.org> References: <20230320145449.336983711@linuxfoundation.org> User-Agent: quilt/0.67 Precedence: bulk X-Mailing-List: patches@lists.linux.dev List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit From: Zheng Wang [ Upstream commit 5000fe6c27827a61d8250a7e4a1d26c3298ef4f6 ] This bug influences both st_nci_i2c_remove and st_nci_spi_remove. Take st_nci_i2c_remove as an example. In st_nci_i2c_probe, it called ndlc_probe and bound &ndlc->sm_work with llt_ndlc_sm_work. When it calls ndlc_recv or timeout handler, it will finally call schedule_work to start the work. When we call st_nci_i2c_remove to remove the driver, there may be a sequence as follows: Fix it by finishing the work before cleanup in ndlc_remove CPU0 CPU1 |llt_ndlc_sm_work st_nci_i2c_remove | ndlc_remove | st_nci_remove | nci_free_device| kfree(ndev) | //free ndlc->ndev | |llt_ndlc_rcv_queue |nci_recv_frame |//use ndlc->ndev Fixes: 35630df68d60 ("NFC: st21nfcb: Add driver for STMicroelectronics ST21NFCB NFC chip") Signed-off-by: Zheng Wang Reviewed-by: Krzysztof Kozlowski Link: https://lore.kernel.org/r/20230312160837.2040857-1-zyytlz.wz@163.com Signed-off-by: Jakub Kicinski Signed-off-by: Sasha Levin --- drivers/nfc/st-nci/ndlc.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/drivers/nfc/st-nci/ndlc.c b/drivers/nfc/st-nci/ndlc.c index e9dc313b333e2..3564e3335a988 100644 --- a/drivers/nfc/st-nci/ndlc.c +++ b/drivers/nfc/st-nci/ndlc.c @@ -286,13 +286,15 @@ EXPORT_SYMBOL(ndlc_probe); void ndlc_remove(struct llt_ndlc *ndlc) { - st_nci_remove(ndlc->ndev); - /* cancel timers */ del_timer_sync(&ndlc->t1_timer); del_timer_sync(&ndlc->t2_timer); ndlc->t2_active = false; ndlc->t1_active = false; + /* cancel work */ + cancel_work_sync(&ndlc->sm_work); + + st_nci_remove(ndlc->ndev); skb_queue_purge(&ndlc->rcv_q); skb_queue_purge(&ndlc->send_q); -- 2.39.2