From: Boris Brezillon boris.brezillon@collabora.com

stable inclusion from stable-v6.6.28 commit 31806711e8a4b75e09b1c43652f2a6420e6e1002 category: bugfix bugzilla: https://gitee.com/src-openeuler/kernel/issues/I9QRMU CVE: CVE-2024-35951

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=...

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commit 1fc9af813b25e146d3607669247d0f970f5a87c3 upstream.

Subject: drm/panfrost: Fix the error path in panfrost_mmu_map_fault_addr()

If some the pages or sgt allocation failed, we shouldn't release the pages ref we got earlier, otherwise we will end up with unbalanced get/put_pages() calls. We should instead leave everything in place and let the BO release function deal with extra cleanup when the object is destroyed, or let the fault handler try again next time it's called.

Fixes: 187d2929206e ("drm/panfrost: Add support for GPU heap allocations") Cc: stable@vger.kernel.org Reviewed-by: Steven Price steven.price@arm.com Reviewed-by: AngeloGioacchino Del Regno angelogioacchino.delregno@collabora.com Signed-off-by: Boris Brezillon boris.brezillon@collabora.com Co-developed-by: Dmitry Osipenko dmitry.osipenko@collabora.com Signed-off-by: Dmitry Osipenko dmitry.osipenko@collabora.com Link: https://patchwork.freedesktop.org/patch/msgid/20240105184624.508603-18-dmitr... Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org

Conflicts: drivers/gpu/drm/panfrost/panfrost_mmu.c Signed-off-by: Cui GaoSheng cuigaosheng1@huawei.com --- drivers/gpu/drm/panfrost/panfrost_mmu.c | 13 +++++++++---- 1 file changed, 9 insertions(+), 4 deletions(-)

diff --git a/drivers/gpu/drm/panfrost/panfrost_mmu.c b/drivers/gpu/drm/panfrost/panfrost_mmu.c index 7ab916a6ba3f..3d822ecc3448 100644 --- a/drivers/gpu/drm/panfrost/panfrost_mmu.c +++ b/drivers/gpu/drm/panfrost/panfrost_mmu.c @@ -447,12 +447,19 @@ static int panfrost_mmu_map_fault_addr(struct panfrost_device *pfdev, int as, mapping_set_unevictable(mapping);

for (i = page_offset; i < page_offset + NUM_FAULT_PAGES; i++) { + /* Can happen if the last fault only partially filled this + * section of the pages array before failing. In that case + * we skip already filled pages. + */ + if (pages[i]) + continue; + pages[i] = shmem_read_mapping_page(mapping, i); if (IS_ERR(pages[i])) { mutex_unlock(&bo->base.pages_lock); ret = PTR_ERR(pages[i]); pages[i] = NULL; - goto err_pages; + goto err_bo; } }

@@ -462,7 +469,7 @@ static int panfrost_mmu_map_fault_addr(struct panfrost_device *pfdev, int as, ret = sg_alloc_table_from_pages(sgt, pages + page_offset, NUM_FAULT_PAGES, 0, SZ_2M, GFP_KERNEL); if (ret) - goto err_pages; + goto err_bo;

ret = dma_map_sgtable(pfdev->dev, sgt, DMA_BIDIRECTIONAL, 0); if (ret) @@ -482,8 +489,6 @@ static int panfrost_mmu_map_fault_addr(struct panfrost_device *pfdev, int as,

err_map: sg_free_table(sgt); -err_pages: - drm_gem_shmem_put_pages(&bo->base); err_bo: panfrost_gem_mapping_put(bomapping); return ret;