From: Michael Kelley <mhklinux@outlook.com> mainline inclusion from mainline-v6.14-rc7 commit aed709355fd05ef747e1af24a1d5d78cd7feb81e category: bugfix bugzilla: https://gitee.com/src-openeuler/kernel/issues/IBY42I CVE: CVE-2025-21978 Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?i... -------------------------------- When a Hyper-V DRM device is probed, the driver allocates MMIO space for the vram, and maps it cacheable. If the device removed, or in the error path for device probing, the MMIO space is released but no unmap is done. Consequently the kernel address space for the mapping is leaked. Fix this by adding iounmap() calls in the device removal path, and in the error path during device probing. Fixes: f1f63cbb705d ("drm/hyperv: Fix an error handling path in hyperv_vmbus_probe()") Fixes: a0ab5abced55 ("drm/hyperv : Removing the restruction of VRAM allocation with PCI bar size") Signed-off-by: Michael Kelley <mhklinux@outlook.com> Reviewed-by: Saurabh Sengar <ssengar@linux.microsoft.com> Tested-by: Saurabh Sengar <ssengar@linux.microsoft.com> Link: https://lore.kernel.org/r/20250210193441.2414-1-mhklinux@outlook.com Signed-off-by: Wei Liu <wei.liu@kernel.org> Message-ID: <20250210193441.2414-1-mhklinux@outlook.com> Signed-off-by: Yifan Qiao <qiaoyifan4@huawei.com> --- drivers/gpu/drm/hyperv/hyperv_drm_drv.c | 2 ++ 1 file changed, 2 insertions(+) diff --git a/drivers/gpu/drm/hyperv/hyperv_drm_drv.c b/drivers/gpu/drm/hyperv/hyperv_drm_drv.c index 8026118c6e03..8a7933f5c6eb 100644 --- a/drivers/gpu/drm/hyperv/hyperv_drm_drv.c +++ b/drivers/gpu/drm/hyperv/hyperv_drm_drv.c @@ -157,6 +157,7 @@ static int hyperv_vmbus_probe(struct hv_device *hdev, return 0; err_free_mmio: + iounmap(hv->vram); vmbus_free_mmio(hv->mem->start, hv->fb_size); err_vmbus_close: vmbus_close(hdev->channel); @@ -175,6 +176,7 @@ static void hyperv_vmbus_remove(struct hv_device *hdev) vmbus_close(hdev->channel); hv_set_drvdata(hdev, NULL); + iounmap(hv->vram); vmbus_free_mmio(hv->mem->start, hv->fb_size); } -- 2.39.2