From 801677040bb284bf0c61e049aed06de843687c59 Mon Sep 17 00:00:00 2001 From: Li RongQing Date: Wed, 21 May 2025 11:46:47 +0800 Subject: [PATCH] vfio/type1: Fix error unwind in migration dirty bitmap allocation [ Upstream commit 4518e5a60c7fbf0cdff393c2681db39d77b4f87e ] When setting up dirty page tracking at the vfio IOMMU backend for device migration, if an error is encountered allocating a tracking bitmap, the unwind loop fails to free previously allocated tracking bitmaps. This occurs because the wrong loop index is used to generate the tracking object. This results in unintended memory usage for the life of the current DMA mappings where bitmaps were successfully allocated. Use the correct loop index to derive the tracking object for freeing during unwind. Fixes: d6a4c185660c ("vfio iommu: Implementation of ioctl for dirty pages tracking") Signed-off-by: Li RongQing Link: https://lore.kernel.org/r/20250521034647.2877-1-lirongqing@baidu.com Signed-off-by: Alex Williamson Signed-off-by: Sasha Levin --- drivers/vfio/vfio_iommu_type1.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/vfio/vfio_iommu_type1.c b/drivers/vfio/vfio_iommu_type1.c index eacd6ec04de5..5fe7aed3672e 100644 --- a/drivers/vfio/vfio_iommu_type1.c +++ b/drivers/vfio/vfio_iommu_type1.c @@ -294,7 +294,7 @@ static int vfio_dma_bitmap_alloc_all(struct vfio_iommu *iommu, size_t pgsize) struct rb_node *p; for (p = rb_prev(n); p; p = rb_prev(p)) { - struct vfio_dma *dma = rb_entry(n, + struct vfio_dma *dma = rb_entry(p, struct vfio_dma, node); vfio_dma_bitmap_free(dma);