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 9C9B9224AE6; Tue, 29 Apr 2025 17:24:06 +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=1745947446; cv=none; b=V769mgdvNekBnKbdHDmycGAAN+OuytRtNR1YDf6ujpBeCCmAvCpSTHiNTsb9N+eq4MZvTf371z63hygCefEgs0vKpXvgMAVAmw2xMqI/Sl0ic7Jn8hF3gOcJzlUcF/Yinzjl5dtASDRmGPnV6ToTkbNDOHy1MeHXebEdO2d58ZQ= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1745947446; c=relaxed/simple; bh=RuVIyE6tUO6lreeOoxhANsf+xIDxLyjoGl1W7lbcWk0=; h=From:To:Cc:Subject:Date:Message-ID:In-Reply-To:References: MIME-Version:Content-Type; b=f5gkmt09+Cb6eVNG00r/7JbRoYRrSgjb0KsNYSicUOXX9YUurK7D+X/Hv5Md2cID+5vVAbCJOnFMjasWWkOgo9jFrrFbumyO+GI+7ZAKvVHEu2CVSCfXFE+dUHzK+DTb/glIpd5UlmQYkVK6HrkNpx+UJWAGyNPcFcTSPzWVl/w= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=linuxfoundation.org header.i=@linuxfoundation.org header.b=dIqu9IZ+; 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="dIqu9IZ+" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 206A4C4CEE3; Tue, 29 Apr 2025 17:24:05 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=linuxfoundation.org; s=korg; t=1745947446; bh=RuVIyE6tUO6lreeOoxhANsf+xIDxLyjoGl1W7lbcWk0=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=dIqu9IZ+K9abphEOg7gpBlhiLqL2coe7PUVJwm52itjXXmTUPgHgr7//vSHjUXi5a rjDLNMHxj2OSx5nqQ1YZIDK2BDejYXmWOXxyg+YHV9MkrwGhZ7ZM9VfNOW5iw5el51 +YtJeT//EGOX6Q8tt6oKBXJsv8cjCKVuazqOVbhg= 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 5.10 283/286] PCI: Fix use-after-free in pci_bus_release_domain_nr() Date: Tue, 29 Apr 2025 18:43:07 +0200 Message-ID: <20250429161119.553094668@linuxfoundation.org> X-Mailer: git-send-email 2.49.0 In-Reply-To: <20250429161107.848008295@linuxfoundation.org> References: <20250429161107.848008295@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-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit 5.10-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 @@ -156,8 +156,6 @@ 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 */ @@ -165,6 +163,9 @@ 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); }