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 38B6C2512FD; Tue, 29 Apr 2025 18:00:04 +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=1745949604; cv=none; b=DNH4tRQXYu2tkUvb1pOXHl/ehm2HrFlG8/9C1qqGg0NM7lE6zHePdPd7SCKAKQZLza7GXilM+hnj0dpg+KezlwnltQdqe+TZMbcQ7kcAvxYPOD7iXzqsOVrt4zqXJNPdWseDEWYXMB9D5OHpyhSc/7WJLeCCDp4MowLIPholYJg= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1745949604; c=relaxed/simple; bh=wugiKlXezYI3AHMB0S1c5CsspWqSPMOSfP5qL1oFwLc=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=mTV6paxTQRni8GTySW/ywUmS/7uorMG20aw8IedpAGOts8PfbXkynMdxJOFoMZD046iE/PdL0trgFKE/7PXWo/1b37ena+CkxyxxqCegaFH6L1fLhQMlMekZdNOnY7VrmYoTJVjG9K29s7V4cLvQtjuHXRdbmENb7iC8zC+5fWA= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=SUxYkuhO; 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="SUxYkuhO" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 9D564C4CEE3; Tue, 29 Apr 2025 18:00:03 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1745949604; bh=wugiKlXezYI3AHMB0S1c5CsspWqSPMOSfP5qL1oFwLc=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=SUxYkuhOQ7iLXRFvhXOuj6Yei/CUFeIWoZQi5lVoQG2CwBM2Atz0+nNpKnlMU91zD ZgTBA7vc3Jeh67ExxaMmHSf6yqLymU3FL/+Bq2lup0kGXXts08n6Aa6jTE+UPJY5e4 XCeelt24mADm0Q2iKHl+ME+u3fLpAv9on9mCq8Lk= From: Greg Kroah-Hartman To: stable@vger.kernel.org Cc: Greg Kroah-Hartman , patches@lists.linux.dev, Jon Hunter , Rob Herring , Bjorn Helgaas , Kuppuswamy Sathyanarayanan , =?UTF-8?q?Pali=20Roh=C3=A1r?= Subject: [PATCH 5.15 371/373] PCI: Fix use-after-free in pci_bus_release_domain_nr() Date: Tue, 29 Apr 2025 18:44:08 +0200 Message-ID: <20250429161138.390217404@linuxfoundation.org> X-Mailer: git-send-email 2.49.0 In-Reply-To: <20250429161123.119104857@linuxfoundation.org> References: <20250429161123.119104857@linuxfoundation.org> User-Agent: quilt/0.68 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-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit 5.15-stable review patch. If anyone has any objections, please let me know. ------------------ From: Rob Herring commit 30ba2d09edb5ea857a1473ae3d820911347ada62 upstream. Commit c14f7ccc9f5d ("PCI: Assign PCI domain IDs by ida_alloc()") introduced a use-after-free bug in the bus removal cleanup. The issue was found with kfence: [ 19.293351] BUG: KFENCE: use-after-free read in pci_bus_release_domain_nr+0x10/0x70 [ 19.302817] Use-after-free read at 0x000000007f3b80eb (in kfence-#115): [ 19.309677] pci_bus_release_domain_nr+0x10/0x70 [ 19.309691] dw_pcie_host_deinit+0x28/0x78 [ 19.309702] tegra_pcie_deinit_controller+0x1c/0x38 [pcie_tegra194] [ 19.309734] tegra_pcie_dw_probe+0x648/0xb28 [pcie_tegra194] [ 19.309752] platform_probe+0x90/0xd8 ... [ 19.311457] kfence-#115: 0x00000000063a155a-0x00000000ba698da8, size=1072, cache=kmalloc-2k [ 19.311469] allocated by task 96 on cpu 10 at 19.279323s: [ 19.311562] __kmem_cache_alloc_node+0x260/0x278 [ 19.311571] kmalloc_trace+0x24/0x30 [ 19.311580] pci_alloc_bus+0x24/0xa0 [ 19.311590] pci_register_host_bridge+0x48/0x4b8 [ 19.311601] pci_scan_root_bus_bridge+0xc0/0xe8 [ 19.311613] pci_host_probe+0x18/0xc0 [ 19.311623] dw_pcie_host_init+0x2c0/0x568 [ 19.311630] tegra_pcie_dw_probe+0x610/0xb28 [pcie_tegra194] [ 19.311647] platform_probe+0x90/0xd8 ... [ 19.311782] freed by task 96 on cpu 10 at 19.285833s: [ 19.311799] release_pcibus_dev+0x30/0x40 [ 19.311808] device_release+0x30/0x90 [ 19.311814] kobject_put+0xa8/0x120 [ 19.311832] device_unregister+0x20/0x30 [ 19.311839] pci_remove_bus+0x78/0x88 [ 19.311850] pci_remove_root_bus+0x5c/0x98 [ 19.311860] dw_pcie_host_deinit+0x28/0x78 [ 19.311866] tegra_pcie_deinit_controller+0x1c/0x38 [pcie_tegra194] [ 19.311883] tegra_pcie_dw_probe+0x648/0xb28 [pcie_tegra194] [ 19.311900] platform_probe+0x90/0xd8 ... [ 19.313579] CPU: 10 PID: 96 Comm: kworker/u24:2 Not tainted 6.2.0 #4 [ 19.320171] Hardware name: /, BIOS 1.0-d7fb19b 08/10/2022 [ 19.325852] Workqueue: events_unbound deferred_probe_work_func The stack trace is a bit misleading as dw_pcie_host_deinit() doesn't directly call pci_bus_release_domain_nr(). The issue turns out to be in pci_remove_root_bus() which first calls pci_remove_bus() which frees the struct pci_bus when its struct device is released. Then pci_bus_release_domain_nr() is called and accesses the freed struct pci_bus. Reordering these fixes the issue. Fixes: c14f7ccc9f5d ("PCI: Assign PCI domain IDs by ida_alloc()") Link: https://lore.kernel.org/r/20230329123835.2724518-1-robh@kernel.org Link: https://lore.kernel.org/r/b529cb69-0602-9eed-fc02-2f068707a006@nvidia.com Reported-by: Jon Hunter Tested-by: Jon Hunter Signed-off-by: Rob Herring Signed-off-by: Bjorn Helgaas Reviewed-by: Kuppuswamy Sathyanarayanan Cc: stable@vger.kernel.org # v6.2+ Cc: Pali Rohár Signed-off-by: Greg Kroah-Hartman --- drivers/pci/remove.c | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) --- a/drivers/pci/remove.c +++ b/drivers/pci/remove.c @@ -157,8 +157,6 @@ void pci_remove_root_bus(struct pci_bus list_for_each_entry_safe(child, tmp, &bus->devices, bus_list) pci_remove_bus_device(child); - pci_remove_bus(bus); - host_bridge->bus = NULL; #ifdef CONFIG_PCI_DOMAINS_GENERIC /* Release domain_nr if it was dynamically allocated */ @@ -166,6 +164,9 @@ void pci_remove_root_bus(struct pci_bus pci_bus_release_domain_nr(bus, host_bridge->dev.parent); #endif + pci_remove_bus(bus); + host_bridge->bus = NULL; + /* remove the host bridge */ device_del(&host_bridge->dev); }