bpf: mark a NULL kfunc argument precisegrafted

check_kfunc_arg() allows bpf_register_is_null() for nullable arguments
w/o marking the underlying scalar register precise. Hence a checkpoint
created on such a path would prune against arbitrary scalar value.

Fixes: 3bda08b63670 ("bpf: Allow NULL buffers in bpf_dynptr_slice(_rw)")
Signed-off-by: Eduard Zingerman <eddyz87@gmail.com>
Link: https://lore.kernel.org/r/20260904-register-is-null-precise-fixes-v1-5-0f5a360ff15d@gmail.com
Signed-off-by: Alexei Starovoitov <ast@kernel.org>

1 files changed, 43 insertions, 0 deletions

diff --git a/drivers/spi/spi-intel-platform.c b/drivers/spi/spi-intel-platform.c
new file mode 100644
index 000000000..6cbed0b2e
--- /dev/null
+++ b/drivers/spi/spi-intel-platform.c
@@ -0,0 +1,43 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Intel PCH/PCU SPI flash platform driver.
+ *
+ * Copyright (C) 2016 - 2022, Intel Corporation
+ * Author: Mika Westerberg <mika.westerberg@linux.intel.com>
+ */
+
+#include <linux/module.h>
+#include <linux/platform_device.h>
+
+#include "spi-intel.h"
+
+static int intel_spi_platform_probe(struct platform_device *pdev)
+{
+	struct intel_spi_boardinfo *info;
+	void __iomem *base;
+
+	info = dev_get_platdata(&pdev->dev);
+	if (!info)
+		return -EINVAL;
+
+	base = devm_platform_ioremap_resource(pdev, 0);
+	if (IS_ERR(base))
+		return PTR_ERR(base);
+
+	return intel_spi_probe(&pdev->dev, base, info);
+}
+
+static struct platform_driver intel_spi_platform_driver = {
+	.probe = intel_spi_platform_probe,
+	.driver = {
+		.name = "intel-spi",
+		.dev_groups = intel_spi_groups,
+	},
+};
+
+module_platform_driver(intel_spi_platform_driver);
+
+MODULE_DESCRIPTION("Intel PCH/PCU SPI flash platform driver");
+MODULE_AUTHOR("Mika Westerberg <mika.westerberg@linux.intel.com>");
+MODULE_LICENSE("GPL v2");
+MODULE_ALIAS("platform:intel-spi");