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 428E93FEB20; Tue, 31 Mar 2026 16:26:27 +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=1774974387; cv=none; b=tRj5Cdqn2qQuJIiJkIWjfn0ct+XZjrVx7ima8roTlKAd4py6yzErilv0FIVNF7uAFN7/IPYL38cOmgkmHZ064xB4iXqo4hPEck6JEQAdPLtmmapVnJPiOnBaqjeV57ZOtiPn3Ji31gDVslZzPNjG3OoGD88Y3YL4PplndGjNgW0= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1774974387; c=relaxed/simple; bh=hXEpCyDpZ6OHbLnZu8fYQlxfqelx6fjZpfUqB99054A=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=p1NWML1DkrdJYjcQYSspVxFTKml91NWkL4hX2ewE46zFf53buVuUgAk3SUkYYpPeOTR7bHMBD8IYwCPeC+6fjy7NtY49JiiAkAzDzMN9Vk4777jL9lJmJUzYWN/bM9ghzYkNwU5ZEKhi1OfvTvhHglShyku/2uwdMHtHg6R3DoM= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=B1jNBa6M; 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="B1jNBa6M" Received: by smtp.kernel.org (Postfix) with ESMTPSA id D14FEC19423; Tue, 31 Mar 2026 16:26:26 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1774974387; bh=hXEpCyDpZ6OHbLnZu8fYQlxfqelx6fjZpfUqB99054A=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=B1jNBa6M4tG/1eMv8UalQxD3Pn+1pWgOksnBhoYGCua3Ph8/8EluIMMNLGqavQpdZ BNw5xEHBKuU9jWUzVzc8w34izlmt9OuZDizQp+xxa01UtKR8FdIOHdKsB+46OkOWBP C01AnmZkKwiDdTyigqDtgJNB4zlN6O4BpTiHXS9I= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Cen Zhang , Luiz Augusto von Dentz , Sasha Levin Subject: [PATCH 6.6 065/175] Bluetooth: btintel: serialize btintel_hw_error() with hci_req_sync_lock Date: Tue, 31 Mar 2026 18:20:49 +0200 Message-ID: <20260331161732.170706201@linuxfoundation.org> X-Mailer: git-send-email 2.53.0 In-Reply-To: <20260331161729.779738837@linuxfoundation.org> References: <20260331161729.779738837@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: Cen Zhang [ Upstream commit 94d8e6fe5d0818e9300e514e095a200bd5ff93ae ] btintel_hw_error() issues two __hci_cmd_sync() calls (HCI_OP_RESET and Intel exception-info retrieval) without holding hci_req_sync_lock(). This lets it race against hci_dev_do_close() -> btintel_shutdown_combined(), which also runs __hci_cmd_sync() under the same lock. When both paths manipulate hdev->req_status/req_rsp concurrently, the close path may free the response skb first, and the still-running hw_error path hits a slab-use-after-free in kfree_skb(). Wrap the whole recovery sequence in hci_req_sync_lock/unlock so it is serialized with every other synchronous HCI command issuer. Below is the data race report and the kasan report: BUG: data-race in __hci_cmd_sync_sk / btintel_shutdown_combined read of hdev->req_rsp at net/bluetooth/hci_sync.c:199 by task kworker/u17:1/83: __hci_cmd_sync_sk+0x12f2/0x1c30 net/bluetooth/hci_sync.c:200 __hci_cmd_sync+0x55/0x80 net/bluetooth/hci_sync.c:223 btintel_hw_error+0x114/0x670 drivers/bluetooth/btintel.c:254 hci_error_reset+0x348/0xa30 net/bluetooth/hci_core.c:1030 write/free by task ioctl/22580: btintel_shutdown_combined+0xd0/0x360 drivers/bluetooth/btintel.c:3648 hci_dev_close_sync+0x9ae/0x2c10 net/bluetooth/hci_sync.c:5246 hci_dev_do_close+0x232/0x460 net/bluetooth/hci_core.c:526 BUG: KASAN: slab-use-after-free in sk_skb_reason_drop+0x43/0x380 net/core/skbuff.c:1202 Read of size 4 at addr ffff888144a738dc by task kworker/u17:1/83: __hci_cmd_sync_sk+0x12f2/0x1c30 net/bluetooth/hci_sync.c:200 __hci_cmd_sync+0x55/0x80 net/bluetooth/hci_sync.c:223 btintel_hw_error+0x186/0x670 drivers/bluetooth/btintel.c:260 Fixes: 973bb97e5aee ("Bluetooth: btintel: Add generic function for handling hardware errors") Signed-off-by: Cen Zhang Signed-off-by: Luiz Augusto von Dentz Signed-off-by: Sasha Levin --- drivers/bluetooth/btintel.c | 11 ++++++++--- 1 file changed, 8 insertions(+), 3 deletions(-) diff --git a/drivers/bluetooth/btintel.c b/drivers/bluetooth/btintel.c index 3773cd9d998d5..25fcd00c6a174 100644 --- a/drivers/bluetooth/btintel.c +++ b/drivers/bluetooth/btintel.c @@ -242,11 +242,13 @@ static void btintel_hw_error(struct hci_dev *hdev, u8 code) bt_dev_err(hdev, "Hardware error 0x%2.2x", code); + hci_req_sync_lock(hdev); + skb = __hci_cmd_sync(hdev, HCI_OP_RESET, 0, NULL, HCI_INIT_TIMEOUT); if (IS_ERR(skb)) { bt_dev_err(hdev, "Reset after hardware error failed (%ld)", PTR_ERR(skb)); - return; + goto unlock; } kfree_skb(skb); @@ -254,18 +256,21 @@ static void btintel_hw_error(struct hci_dev *hdev, u8 code) if (IS_ERR(skb)) { bt_dev_err(hdev, "Retrieving Intel exception info failed (%ld)", PTR_ERR(skb)); - return; + goto unlock; } if (skb->len != 13) { bt_dev_err(hdev, "Exception info size mismatch"); kfree_skb(skb); - return; + goto unlock; } bt_dev_err(hdev, "Exception info %s", (char *)(skb->data + 1)); kfree_skb(skb); + +unlock: + hci_req_sync_unlock(hdev); } int btintel_version_info(struct hci_dev *hdev, struct intel_version *ver) -- 2.51.0