From 8e1664b9ee43608eb973d357ae5d858d30cbc9ca Mon Sep 17 00:00:00 2001 From: Xiao Kan <814091656@qq.com> Date: Wed, 14 Jan 2026 08:22:26 -0500 Subject: [PATCH] drm: Account property blob allocations to memcg [ Upstream commit 26b4309a3ab82a0697751cde52eb336c29c19035 ] DRM_IOCTL_MODE_CREATEPROPBLOB allows userspace to allocate arbitrary-sized property blobs backed by kernel memory. Currently, the blob data allocation is not accounted to the allocating process's memory cgroup, allowing unprivileged users to trigger unbounded kernel memory consumption and potentially cause system-wide OOM. Mark the property blob data allocation with GFP_KERNEL_ACCOUNT so that the memory is properly charged to the caller's memcg. This ensures existing cgroup memory limits apply and prevents uncontrolled kernel memory growth without introducing additional policy or per-file limits. Signed-off-by: Xiao Kan <814091656@qq.com> Signed-off-by: Xiao Kan Link: https://patch.msgid.link/tencent_D12AA2DEDE6F359E1AF59405242FB7A5FD05@qq.com Signed-off-by: Maxime Ripard Signed-off-by: Sasha Levin --- drivers/gpu/drm/drm_property.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/gpu/drm/drm_property.c b/drivers/gpu/drm/drm_property.c index 596272149a35..3c88b5fbdf28 100644 --- a/drivers/gpu/drm/drm_property.c +++ b/drivers/gpu/drm/drm_property.c @@ -562,7 +562,7 @@ drm_property_create_blob(struct drm_device *dev, size_t length, if (!length || length > INT_MAX - sizeof(struct drm_property_blob)) return ERR_PTR(-EINVAL); - blob = kvzalloc(sizeof(struct drm_property_blob)+length, GFP_KERNEL); + blob = kvzalloc(sizeof(struct drm_property_blob) + length, GFP_KERNEL_ACCOUNT); if (!blob) return ERR_PTR(-ENOMEM);