From e615a191216e3fb4e9c0d239007f2b0cd48f28bf Mon Sep 17 00:00:00 2001 From: Dan Williams Date: Thu, 13 Jun 2019 15:56:24 -0700 Subject: PCI/P2PDMA: fix the gen_pool_add_virt() failure path MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit The pci_p2pdma_add_resource() implementation immediately frees the pgmap if gen_pool_add_virt() fails. However, that means that when @dev triggers a devres release devm_memremap_pages_release() will crash trying to access the freed @pgmap. Use the new devm_memunmap_pages() to manually free the mapping in the error path. Link: http://lkml.kernel.org/r/155727337603.292046.13101332703665246702.stgit@dwillia2-desk3.amr.corp.intel.com Signed-off-by: Dan Williams Fixes: 52916982af48 ("PCI/P2PDMA: Support peer-to-peer memory") Reviewed-by: Ira Weiny Acked-by: Bjorn Helgaas Reviewed-by: Logan Gunthorpe Cc: Christoph Hellwig Cc: Greg Kroah-Hartman Cc: "Jérôme Glisse" Cc: "Rafael J. Wysocki" Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- drivers/pci/p2pdma.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) (limited to 'drivers') diff --git a/drivers/pci/p2pdma.c b/drivers/pci/p2pdma.c index 742928d0053e..d5736b31ce66 100644 --- a/drivers/pci/p2pdma.c +++ b/drivers/pci/p2pdma.c @@ -208,13 +208,15 @@ int pci_p2pdma_add_resource(struct pci_dev *pdev, int bar, size_t size, pci_bus_address(pdev, bar) + offset, resource_size(&pgmap->res), dev_to_node(&pdev->dev)); if (error) - goto pgmap_free; + goto pages_free; pci_info(pdev, "added peer-to-peer DMA memory %pR\n", &pgmap->res); return 0; +pages_free: + devm_memunmap_pages(&pdev->dev, pgmap); pgmap_free: devm_kfree(&pdev->dev, pgmap); return error; -- cgit v1.2.3-58-ga151