From mboxrd@z Thu Jan 1 00:00:00 1970 Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.remote-ip=100.103.45.18 ARC-Seal: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; cv=none; t=1793831507; b=JiO21wmBtv3Ox6ShJozzqBLjZwrOAtWGQtB1czwaqRO820ueXTrbmbxzOj2WepQgxPaX mIW9eKFrjGbCGJ/M0H9utQM1ZIDHYD0QJxdoyhsBFo+BGz5/Yt/FPpEUROko1XRvoZTCQ rARW2ztzX8uiyLjW2ySP2CA3VKtRLLh46WQ61Hzhk0F4BHE8mq33wdc6f4XCDBbUr628Y glh4c+bXVqu5j3P/o+xPB8I3a64D4Av975QPTGBYY7FEbQt7KbLMzBP2laRIC3ZEstuAj g1c+dmPhyFxxd0pgjZiqgCTJilHvw91Td3RFQOBofJo/gYIOZVo68zft0ZtxMOiDrWw== ARC-Message-Signature: i=1; d=subspace.kernel.org; s=arc20261015; a=rsa-sha256; c=relaxed/relaxed; t=1793831507; h=Received:DKIM-Signature:From:To:Cc:Subject:Date:Message-ID:X-Mailer: In-Reply-To:References:User-Agent:X-stable:X-Patchwork-Hint: MIME-Version:Content-Transfer-Encoding; bh=vTNTABf/MgwPfSGxY+Qzklm4eg+YiD8Rk5hJJ74DiRk=; b=bh0gBYBnLeemEpiUceeakgk5hHhkjujVDhDB0qNrGUWjarR40qhVFDG7AXEr73eKijUE XwpfRHZk8op3TGO3/xE92Ggcqn3LPiDUptbp55SIdoR6FmVldMjQ+Xlldasy8HbEwP1I1 q11jQGghsUi/7CVO/ZKwW/iE8bSR0HnPrg609Z3IP1/pC8C9Lv9tg6DH7wfS9GY9llUsT +005EHl08ddeVW4kOyQvKRJaiIiwfuHwn4GTsNiHcPeiXuMAvbP4ZSibbJnoa8dhHEPKq dr6aXt+zvdSqHHhJcpfXkzcDxk3sB1gtGL6AAV5e+27UeQq8rfQqgd1Y3kJk43AFv8g== ARC-Authentication-Results: i=1; smtp.subspace.kernel.org; dkim=pass header.d=linuxfoundation.org header.i=@linuxfoundation.org header.a=rsa-sha256 header.s=korg header.b=eIBl3d4j; arc=none smtp.remote-ip=100.103.45.18 Received: from smtp.kernel.org (quasi.space.kernel.org [100.103.45.18]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature ECDSA (prime256v1)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id F2C25606D80A; Wed, 4 Nov 2026 22:31:46 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key, unprotected) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.a=rsa-sha256 header.s=korg header.b=eIBl3d4j Received: by smtp.kernel.org (Postfix) with ESMTPSA id 8A91D1F00A02; Wed, 4 Nov 2026 22:31:46 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1793831506; bh=vTNTABf/MgwPfSGxY+Qzklm4eg+YiD8Rk5hJJ74DiRk=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=eIBl3d4j8ENVFidH4KL0T4OQ437/VCqN7hJyCtRPcwvnYOiisvMWzlU+zSnBKkj/x FyXaqrfKZWLrV70qj1T7MSIhji1BQKVpDNuuyLAy21FH9M/UjlYfLtc6yRu53pGURX HmehKiC1i5KV8YKr5Plvgm0rPGNhgiqTcM5bOVL4= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Sean Young , Hans Verkuil Subject: [PATCH 6.18 0744/1005] media: rc: Ensure registered is cleared in error path Date: Wed, 4 Nov 2026 16:07:57 -0500 Message-ID: <20261104211104.307610334@linuxfoundation.org> X-Mailer: git-send-email 2.56.0 In-Reply-To: <20261104211043.516122098@linuxfoundation.org> References: <20261104211043.516122098@linuxfoundation.org> User-Agent: quilt/0.69 X-stable: review X-Patchwork-Hint: ignore X-Mailing-List: patches@lists.linux.dev List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 Content-Transfer-Encoding: 8bit 6.18-stable review patch. If anyone has any objections, please let me know. ------------------ From: Sean Young commit 37efd09ba2c62e46e3a3a793025c186f8cd1a417 upstream. If rc_register_device() fails, ensure that registered is not set to true. If lirc_register() succeeded, then userspace could have an open file descriptor open. This leads to a use-after-free. lirc_unregister() must be called with registered = false, else there is a possibility that an fd is open and polling, which would never return POLLERR unless registered is false. Note that registered must be changed under dev->lock, many functions read registered under lock (e.g. lirc_ioctl). Fixes: dccc0c3ddf8f ("media: rc: fix race between unregister and urb/irq callbacks") Signed-off-by: Sean Young Cc: stable@vger.kernel.org Acked-by: Hans Verkuil Signed-off-by: Greg Kroah-Hartman --- drivers/media/rc/rc-main.c | 16 ++++++++++++---- 1 file changed, 12 insertions(+), 4 deletions(-) --- a/drivers/media/rc/rc-main.c +++ b/drivers/media/rc/rc-main.c @@ -1929,7 +1929,8 @@ int rc_register_device(struct rc_dev *de goto out_raw; } - dev->registered = true; + scoped_guard(mutex, &dev->lock) + dev->registered = true; rc = device_add(&dev->dev); if (rc) @@ -1949,7 +1950,7 @@ int rc_register_device(struct rc_dev *de if (dev->allowed_protocols != RC_PROTO_BIT_CEC) { rc = lirc_register(dev); if (rc < 0) - goto out_dev; + goto out_lirc; } if (dev->driver_type != RC_DRIVER_IR_RAW_TX) { @@ -1972,11 +1973,18 @@ int rc_register_device(struct rc_dev *de out_rx: rc_free_rx_device(dev); out_lirc: - if (dev->allowed_protocols != RC_PROTO_BIT_CEC) + scoped_guard(mutex, &dev->lock) + dev->registered = false; + + if (device_is_registered(&dev->lirc_dev)) lirc_unregister(dev); -out_dev: device_del(&dev->dev); + /* registered already cleared above */ + goto out_free_table; out_rx_free: + scoped_guard(mutex, &dev->lock) + dev->registered = false; +out_free_table: ir_free_table(&dev->rc_map); out_raw: ir_raw_event_free(dev);