lkml.org 
[lkml]   [2017]   [Dec]   [12]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
/
Date
From
SubjectRe: [PATCH 1/2] PCI: rcar: Fix use-after-free in probe error path
On Thu, Dec 07, 2017 at 11:15:19AM +0100, Geert Uytterhoeven wrote:
> If CONFIG_DEBUG_SLAB=y, and no PCIe card is inserted, the kernel crashes
> during probe on r8a7791/koelsch:
>
> rcar-pcie fe000000.pcie: PCIe link down
> Unable to handle kernel paging request at virtual address 6b6b6b6b
>
> (seeing this message requires earlycon and keep_bootcon).
>
> Indeed, pci_free_host_bridge() frees the PCI host bridge, including the
> embedded rcar_pcie object, so pci_free_resource_list() must not be
> called afterwards.
>
> To fix this, move the call to pci_free_resource_list() up, and update the
> label name accordingly.
>
> Fixes: ddd535f1ea3eb27e ("PCI: rcar: Fix memory leak when no PCIe card is inserted")
> Signed-off-by: Geert Uytterhoeven <geert+renesas@glider.be>

Applied with Simon's and Lorenzo's acks to for-linus for v4.15, thanks!

I'll leave the second patch up to Lorenzo for v4.16, since it doesn't seem
as critical.

> ---
> drivers/pci/host/pcie-rcar.c | 8 ++++----
> 1 file changed, 4 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/pci/host/pcie-rcar.c b/drivers/pci/host/pcie-rcar.c
> index 12796eccb2befd91..52ab3cb0a0bfe065 100644
> --- a/drivers/pci/host/pcie-rcar.c
> +++ b/drivers/pci/host/pcie-rcar.c
> @@ -1128,12 +1128,12 @@ static int rcar_pcie_probe(struct platform_device *pdev)
> err = rcar_pcie_get_resources(pcie);
> if (err < 0) {
> dev_err(dev, "failed to request resources: %d\n", err);
> - goto err_free_bridge;
> + goto err_free_resource_list;
> }
>
> err = rcar_pcie_parse_map_dma_ranges(pcie, dev->of_node);
> if (err)
> - goto err_free_bridge;
> + goto err_free_resource_list;
>
> pm_runtime_enable(dev);
> err = pm_runtime_get_sync(dev);
> @@ -1176,9 +1176,9 @@ static int rcar_pcie_probe(struct platform_device *pdev)
> err_pm_disable:
> pm_runtime_disable(dev);
>
> -err_free_bridge:
> - pci_free_host_bridge(bridge);
> +err_free_resource_list:
> pci_free_resource_list(&pcie->resources);
> + pci_free_host_bridge(bridge);
>
> return err;
> }
> --
> 2.7.4
>

\
 
 \ /
  Last update: 2017-12-12 20:30    [W:0.141 / U:5.240 seconds]
©2003-2018 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site