From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-alma10-1.taild15c8.ts.net [100.103.45.18]) (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 45703345EB5; Sat, 12 Sep 2026 19:51:03 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=100.103.45.18 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789242664; cv=none; b=Okm5GJR/ZaDMUYRECIFywHtnni3PDW2u71AtgCDbIdD3BXdriBnqayAvV4++kb8opobCgEmILIWRi6xly3T45P0u/kPgzAtD5gKr93jAd0QWQQR8Mv1BXkdJ4INE5lNxXEwcMT8tf37bC41jPcX7Wy+pPVD/fSHmm2+/mZAepD8= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1789242664; c=relaxed/simple; bh=zmZIWy54c1mzrW4TkosrvR8/SBJlwallOr1ks9eapG0=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version; b=UhQ9J+r1q5kDdh0GQ2+YzpAcciu/iJ7JAtQTkRHQQLEOc11XMf6o6o/G5lyVKX/mi5KcZ50H8r8ZkOgPFR1mX0LnbM2ygEivB0pLkrHpniWnL4WxIsU5NWdbFG0CbXr1zpU2OB99IZTJ7Ag9xohA8iCkQMHbsLdC93V6BAIfdt4= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=BSD3M9cu; arc=none smtp.client-ip=100.103.45.18 Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b="BSD3M9cu" Received: by smtp.kernel.org (Postfix) with ESMTPSA id A0B6B1F000FF; Sat, 12 Sep 2026 19:51:02 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linuxfoundation.org; s=korg; t=1789242663; bh=8HIWbjA+TIYhmUpBjqZT8fhocF1XfUL+l+c9KmQXnlA=; h=From:To:Cc:Subject:Date:In-Reply-To:References; b=BSD3M9cuMMO1EEKCg0mFt0MgT5Rrt7N1law4y9ZomhGs2fCrTpdSEuFWI8QUn3JPb JIeKb32EfZtDd1efsU7b4UbrK9l1xanm/3XKD926B0LlAcTxvogFEE2c3ZTKYnyd4C 76BNS1Z1kce4T+DZ6Xyfd9I5qCP0hMaGDb0xtJPY= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Sashiko AI review , Chen Pei , "Rafael J. Wysocki" , Sasha Levin Subject: [PATCH 5.10 484/798] ACPI: PCI: Clear driver_data on all paths that free the acpi_pci_root Date: Sat, 12 Sep 2026 09:01:52 +0200 Message-ID: <20260912065528.234457092@linuxfoundation.org> X-Mailer: git-send-email 2.55.0 In-Reply-To: <20260912065516.948645775@linuxfoundation.org> References: <20260912065516.948645775@linuxfoundation.org> User-Agent: quilt/0.69 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 5.10-stable review patch. If anyone has any objections, please let me know. ------------------ From: Chen Pei [ Upstream commit 8a742141f7ab84975aa758b775567ef4740ef0cf ] acpi_pci_root_add() assigns the freshly allocated root to device->driver_data before dmar_device_add() and pci_acpi_scan_root(). Both failure paths reach the end: label where root is kfree()'d, but only the pci_acpi_scan_root() path clears driver_data first. When dmar_device_add() fails during a hot-add, root is freed while device->driver_data still points at it. The ACPI core does not clear driver_data on attach failure, so a later acpi_pci_find_root() call may dereference this dangling pointer. acpi_pci_root_remove() has the same problem: it frees root without clearing device->driver_data, leaving a dangling pointer behind after the root bridge is removed. Move the NULL assignment to the shared end: label so every error path in acpi_pci_root_add() clears driver_data before freeing root, and clear it in acpi_pci_root_remove() as well, so the object is never left reachable through driver_data after being freed. Fixes: db89b4f0dbab ("ACPI: catch calls of acpi_driver_data on pointer of wrong type") Reported-by: Sashiko AI review Link: https://sashiko.dev/#/patchset/20260526025118.38935-1-cp0613@linux.alibaba.com Link: https://sashiko.dev/#/patchset/20260707121258.11640-1-cp0613@linux.alibaba.com Signed-off-by: Chen Pei Link: https://patch.msgid.link/20260715135048.3278-1-cp0613@linux.alibaba.com Signed-off-by: Rafael J. Wysocki Signed-off-by: Sasha Levin --- drivers/acpi/pci_root.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/drivers/acpi/pci_root.c b/drivers/acpi/pci_root.c index d972ea057a035..326c3169320ce 100644 --- a/drivers/acpi/pci_root.c +++ b/drivers/acpi/pci_root.c @@ -609,7 +609,6 @@ static int acpi_pci_root_add(struct acpi_device *device, dev_err(&device->dev, "Bus %04x:%02x not present in PCI namespace\n", root->segment, (unsigned int)root->secondary.start); - device->driver_data = NULL; result = -ENODEV; goto remove_dmar; } @@ -645,6 +644,7 @@ static int acpi_pci_root_add(struct acpi_device *device, if (hotadd) dmar_device_remove(handle); end: + device->driver_data = NULL; kfree(root); return result; } @@ -668,6 +668,7 @@ static void acpi_pci_root_remove(struct acpi_device *device) pci_unlock_rescan_remove(); + device->driver_data = NULL; kfree(root); } -- 2.53.0