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 1E812212560; Sun, 7 Sep 2025 20:29:16 +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=1757276958; cv=none; b=NmIZ/rCHUkC6tQs2XksvVgwMljJh9HeUrjlia0Rci04hoX0VPBYEEG0L/rGerizkH2FVctHT2uLQtTXIW9HO+8qO/Z3X0F4OJOSJUyTXmXzOv0JNFfbNLg+Ud2ch5E5Of6K8DWYu6L8JaX3iSgE22qewyTsSDfIL8Uglec6T+s8= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1757276958; c=relaxed/simple; bh=HPzPyrG2kNU671PJQ7cdj67D+DFG3IbIwIy4mPjVFy4=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=gsxqD7B/woi7Eml66SPm6lhaw8DxVC65jOs0W4yN147zkY/1sTipaQEgbzkrO1u8PwN8HyqJAA3rB/ktP4+LW0s1nikHyseOGzxjQkKv8C6g64+rLqfxlkhORc5xujmP4vnSt/wZ3qa36TsFw8DEdhqaAQ0Y6HwvqqYj5Nug3hQ= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=QDrFO6wy; 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="QDrFO6wy" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 3D6C5C4CEF0; Sun, 7 Sep 2025 20:29:16 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1757276956; bh=HPzPyrG2kNU671PJQ7cdj67D+DFG3IbIwIy4mPjVFy4=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=QDrFO6wyYn1u7KFcSuk5GSkajWs4y4eP+IbGnL7mhnCZM55Oc8gmT+GacLnC8BuHx jsyqlmGrK5i7vFdAaoSxJaTIJVRPTPGaMUJerGejVjUWWvPGtYPIgE5I22+bJAWzRx Xuqc+v4zurEqAi5t/aLduFUnzkqSMbgFXtTcpLII= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Ivan Pravdin , Paul Menzel , Luiz Augusto von Dentz , Sasha Levin Subject: [PATCH 6.12 042/175] Bluetooth: vhci: Prevent use-after-free by removing debugfs files early Date: Sun, 7 Sep 2025 21:57:17 +0200 Message-ID: <20250907195615.850381314@linuxfoundation.org> X-Mailer: git-send-email 2.51.0 In-Reply-To: <20250907195614.892725141@linuxfoundation.org> References: <20250907195614.892725141@linuxfoundation.org> User-Agent: quilt/0.68 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 6.12-stable review patch. If anyone has any objections, please let me know. ------------------ From: Ivan Pravdin [ Upstream commit 28010791193a4503f054e8d69a950ef815deb539 ] Move the creation of debugfs files into a dedicated function, and ensure they are explicitly removed during vhci_release(), before associated data structures are freed. Previously, debugfs files such as "force_suspend", "force_wakeup", and others were created under hdev->debugfs but not removed in vhci_release(). Since vhci_release() frees the backing vhci_data structure, any access to these files after release would result in use-after-free errors. Although hdev->debugfs is later freed in hci_release_dev(), user can access files after vhci_data is freed but before hdev->debugfs is released. Fixes: ab4e4380d4e1 ("Bluetooth: Add vhci devcoredump support") Signed-off-by: Ivan Pravdin Reviewed-by: Paul Menzel Signed-off-by: Luiz Augusto von Dentz Signed-off-by: Sasha Levin --- drivers/bluetooth/hci_vhci.c | 57 ++++++++++++++++++++++++++---------- 1 file changed, 41 insertions(+), 16 deletions(-) diff --git a/drivers/bluetooth/hci_vhci.c b/drivers/bluetooth/hci_vhci.c index 9ac22e4a070be..59872e73c1878 100644 --- a/drivers/bluetooth/hci_vhci.c +++ b/drivers/bluetooth/hci_vhci.c @@ -380,6 +380,28 @@ static const struct file_operations force_devcoredump_fops = { .write = force_devcd_write, }; +static void vhci_debugfs_init(struct vhci_data *data) +{ + struct hci_dev *hdev = data->hdev; + + debugfs_create_file("force_suspend", 0644, hdev->debugfs, data, + &force_suspend_fops); + + debugfs_create_file("force_wakeup", 0644, hdev->debugfs, data, + &force_wakeup_fops); + + if (IS_ENABLED(CONFIG_BT_MSFTEXT)) + debugfs_create_file("msft_opcode", 0644, hdev->debugfs, data, + &msft_opcode_fops); + + if (IS_ENABLED(CONFIG_BT_AOSPEXT)) + debugfs_create_file("aosp_capable", 0644, hdev->debugfs, data, + &aosp_capable_fops); + + debugfs_create_file("force_devcoredump", 0644, hdev->debugfs, data, + &force_devcoredump_fops); +} + static int __vhci_create_device(struct vhci_data *data, __u8 opcode) { struct hci_dev *hdev; @@ -433,22 +455,8 @@ static int __vhci_create_device(struct vhci_data *data, __u8 opcode) return -EBUSY; } - debugfs_create_file("force_suspend", 0644, hdev->debugfs, data, - &force_suspend_fops); - - debugfs_create_file("force_wakeup", 0644, hdev->debugfs, data, - &force_wakeup_fops); - - if (IS_ENABLED(CONFIG_BT_MSFTEXT)) - debugfs_create_file("msft_opcode", 0644, hdev->debugfs, data, - &msft_opcode_fops); - - if (IS_ENABLED(CONFIG_BT_AOSPEXT)) - debugfs_create_file("aosp_capable", 0644, hdev->debugfs, data, - &aosp_capable_fops); - - debugfs_create_file("force_devcoredump", 0644, hdev->debugfs, data, - &force_devcoredump_fops); + if (!IS_ERR_OR_NULL(hdev->debugfs)) + vhci_debugfs_init(data); hci_skb_pkt_type(skb) = HCI_VENDOR_PKT; @@ -650,6 +658,21 @@ static int vhci_open(struct inode *inode, struct file *file) return 0; } +static void vhci_debugfs_remove(struct hci_dev *hdev) +{ + debugfs_lookup_and_remove("force_suspend", hdev->debugfs); + + debugfs_lookup_and_remove("force_wakeup", hdev->debugfs); + + if (IS_ENABLED(CONFIG_BT_MSFTEXT)) + debugfs_lookup_and_remove("msft_opcode", hdev->debugfs); + + if (IS_ENABLED(CONFIG_BT_AOSPEXT)) + debugfs_lookup_and_remove("aosp_capable", hdev->debugfs); + + debugfs_lookup_and_remove("force_devcoredump", hdev->debugfs); +} + static int vhci_release(struct inode *inode, struct file *file) { struct vhci_data *data = file->private_data; @@ -661,6 +684,8 @@ static int vhci_release(struct inode *inode, struct file *file) hdev = data->hdev; if (hdev) { + if (!IS_ERR_OR_NULL(hdev->debugfs)) + vhci_debugfs_remove(hdev); hci_unregister_dev(hdev); hci_free_dev(hdev); } -- 2.50.1