agp/intel: Fix a memory leak on module initialisation failure

[ Upstream commit b975abbd382fe442713a4c233549abb90e57c22b ]

In intel_gtt_setup_scratch_page(), pointer "page" is not released if
pci_dma_mapping_error() return an error, leading to a memory leak on
module initialisation failure.  Simply fix this issue by freeing "page"
before return.

Fixes: 0e87d2b06cb46 ("intel-gtt: initialize our own scratch page")
Signed-off-by: Qiushi Wu <wu000273@umn.edu>
Reviewed-by: Chris Wilson <chris@chris-wilson.co.uk>
Signed-off-by: Chris Wilson <chris@chris-wilson.co.uk>
Link: https://patchwork.freedesktop.org/patch/msgid/20200522083451.7448-1-chris@chris-wilson.co.uk
Signed-off-by: Sasha Levin <sashal@kernel.org>

diff --git a/drivers/char/agp/intel-gtt.c b/drivers/char/agp/intel-gtt.c
index 871e7f4994e8c0054a43bc1316bea2288f4b47da..667882e996ecca53a62d57d836f6afa2dadd06e4 100644 (file)
--- a/drivers/char/agp/intel-gtt.c
+++ b/drivers/char/agp/intel-gtt.c
@@ -303,8 +303,10 @@ static int intel_gtt_setup_scratch_page(void)
        if (intel_private.needs_dmar) {
                dma_addr = pci_map_page(intel_private.pcidev, page, 0,
                                    PAGE_SIZE, PCI_DMA_BIDIRECTIONAL);
-               if (pci_dma_mapping_error(intel_private.pcidev, dma_addr))
+               if (pci_dma_mapping_error(intel_private.pcidev, dma_addr)) {
+                       __free_page(page);
                        return -EINVAL;
+               }
 
                intel_private.scratch_page_dma = dma_addr;
        } else