[PATCH 5.9 555/757] vfio iommu type1: Fix memory leak in vfio_iommu_type1_pin_pages

From: Greg Kroah-Hartman
Date: Tue Oct 27 2020 - 12:40:33 EST


From: Xiaoyang Xu <xuxiaoyang2@xxxxxxxxxx>

[ Upstream commit 2e6cfd496f5b57034cf2aec738799571b5a52124 ]

pfn is not added to pfn_list when vfio_add_to_pfn_list fails.
vfio_unpin_page_external will exit directly without calling
vfio_iova_put_vfio_pfn. This will lead to a memory leak.

Fixes: a54eb55045ae ("vfio iommu type1: Add support for mediated devices")
Signed-off-by: Xiaoyang Xu <xuxiaoyang2@xxxxxxxxxx>
[aw: simplified logic, add Fixes]
Signed-off-by: Alex Williamson <alex.williamson@xxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/vfio/vfio_iommu_type1.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/drivers/vfio/vfio_iommu_type1.c b/drivers/vfio/vfio_iommu_type1.c
index d0438388feebe..9dde5ed852fd0 100644
--- a/drivers/vfio/vfio_iommu_type1.c
+++ b/drivers/vfio/vfio_iommu_type1.c
@@ -693,7 +693,8 @@ static int vfio_iommu_type1_pin_pages(void *iommu_data,

ret = vfio_add_to_pfn_list(dma, iova, phys_pfn[i]);
if (ret) {
- vfio_unpin_page_external(dma, iova, do_accounting);
+ if (put_pfn(phys_pfn[i], dma->prot) && do_accounting)
+ vfio_lock_acct(dma, -1, true);
goto pin_unwind;
}

--
2.25.1