selftests/bpf: Test packet range of pointers sharing an idgrafted

Add tests where two packet pointers share an id and tightening one
pointer's umax from its var_off would put it less than their constant
distance from the other's umax: with an index & 0x38 capped at 50, the
base pointer keeps umax 50, so the pointer 8 bytes further on must keep
umax 58, even though its known bits allow at most 56.

These refused a valid program or accepted an out-of-bounds access before
the fix:

- check the advanced copy, load through the base: valid, was refused;
- check the base, load the byte at base + 1 through a copy advanced by
  8: was accepted;
- check base + 4, load 4 bytes at base + 2 through base + 8: reads two
  bytes past the checked range, was accepted;
- the same as the second with data_meta pointers checked against data:
  was accepted.

These pass with and without the fix and cover nearby paths:

- subtract an unknown scalar from a checked pointer and load below it
  (the range is kept across a new id);
- reach a load through two paths whose checks cover 8 and 7 bytes after
  the loaded pointer; the second path must not be pruned by the first;
- spill a copy of a pointer, check the pointer, fill the copy and load
  one byte past the checked range: the load is refused, and the copy
  has the range of the check.

Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20261001145255.855630-2-alexei.starovoitov@gmail.com
Signed-off-by: Kumar Kartikeya Dwivedi <memxor@gmail.com>

1 files changed, 163 insertions, 0 deletions

diff --git a/drivers/usb/phy/phy-isp1301.c b/drivers/usb/phy/phy-isp1301.c
new file mode 100644
index 000000000..73cc70e95
--- /dev/null
+++ b/drivers/usb/phy/phy-isp1301.c
@@ -0,0 +1,163 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * NXP ISP1301 USB transceiver driver
+ *
+ * Copyright (C) 2012 Roland Stigge
+ *
+ * Author: Roland Stigge <stigge@antcom.de>
+ */
+
+#include <linux/module.h>
+#include <linux/mutex.h>
+#include <linux/i2c.h>
+#include <linux/usb/phy.h>
+#include <linux/usb/isp1301.h>
+
+#define DRV_NAME		"isp1301"
+
+struct isp1301 {
+	struct usb_phy		phy;
+	struct mutex		mutex;
+
+	struct i2c_client	*client;
+};
+
+#define phy_to_isp(p)		(container_of((p), struct isp1301, phy))
+
+static const struct i2c_device_id isp1301_id[] = {
+	{ .name = "isp1301" },
+	{ }
+};
+MODULE_DEVICE_TABLE(i2c, isp1301_id);
+
+static const struct of_device_id isp1301_of_match[] = {
+	{.compatible = "nxp,isp1301" },
+	{ },
+};
+MODULE_DEVICE_TABLE(of, isp1301_of_match);
+
+static struct i2c_client *isp1301_i2c_client;
+
+static int __isp1301_write(struct isp1301 *isp, u8 reg, u8 value, u8 clear)
+{
+	return i2c_smbus_write_byte_data(isp->client, reg | clear, value);
+}
+
+static int isp1301_write(struct isp1301 *isp, u8 reg, u8 value)
+{
+	return __isp1301_write(isp, reg, value, 0);
+}
+
+static int isp1301_clear(struct isp1301 *isp, u8 reg, u8 value)
+{
+	return __isp1301_write(isp, reg, value, ISP1301_I2C_REG_CLEAR_ADDR);
+}
+
+static int isp1301_phy_init(struct usb_phy *phy)
+{
+	struct isp1301 *isp = phy_to_isp(phy);
+
+	/* Disable transparent UART mode first */
+	isp1301_clear(isp, ISP1301_I2C_MODE_CONTROL_1, MC1_UART_EN);
+	isp1301_clear(isp, ISP1301_I2C_MODE_CONTROL_1, ~MC1_SPEED_REG);
+	isp1301_write(isp, ISP1301_I2C_MODE_CONTROL_1, MC1_SPEED_REG);
+	isp1301_clear(isp, ISP1301_I2C_MODE_CONTROL_2, ~0);
+	isp1301_write(isp, ISP1301_I2C_MODE_CONTROL_2, (MC2_BI_DI | MC2_PSW_EN
+				| MC2_SPD_SUSP_CTRL));
+
+	isp1301_clear(isp, ISP1301_I2C_OTG_CONTROL_1, ~0);
+	isp1301_write(isp, ISP1301_I2C_MODE_CONTROL_1, MC1_DAT_SE0);
+	isp1301_write(isp, ISP1301_I2C_OTG_CONTROL_1, (OTG1_DM_PULLDOWN
+				| OTG1_DP_PULLDOWN));
+	isp1301_clear(isp, ISP1301_I2C_OTG_CONTROL_1, (OTG1_DM_PULLUP
+				| OTG1_DP_PULLUP));
+
+	/* mask all interrupts */
+	isp1301_clear(isp, ISP1301_I2C_INTERRUPT_LATCH, ~0);
+	isp1301_clear(isp, ISP1301_I2C_INTERRUPT_FALLING, ~0);
+	isp1301_clear(isp, ISP1301_I2C_INTERRUPT_RISING, ~0);
+
+	return 0;
+}
+
+static int isp1301_phy_set_vbus(struct usb_phy *phy, int on)
+{
+	struct isp1301 *isp = phy_to_isp(phy);
+
+	if (on)
+		isp1301_write(isp, ISP1301_I2C_OTG_CONTROL_1, OTG1_VBUS_DRV);
+	else
+		isp1301_clear(isp, ISP1301_I2C_OTG_CONTROL_1, OTG1_VBUS_DRV);
+
+	return 0;
+}
+
+static int isp1301_probe(struct i2c_client *client)
+{
+	struct isp1301 *isp;
+	struct usb_phy *phy;
+
+	isp = devm_kzalloc(&client->dev, sizeof(*isp), GFP_KERNEL);
+	if (!isp)
+		return -ENOMEM;
+
+	isp->client = client;
+	mutex_init(&isp->mutex);
+
+	phy = &isp->phy;
+	phy->dev = &client->dev;
+	phy->label = DRV_NAME;
+	phy->init = isp1301_phy_init;
+	phy->set_vbus = isp1301_phy_set_vbus;
+	phy->type = USB_PHY_TYPE_USB2;
+
+	i2c_set_clientdata(client, isp);
+	usb_add_phy_dev(phy);
+
+	isp1301_i2c_client = client;
+
+	return 0;
+}
+
+static void isp1301_remove(struct i2c_client *client)
+{
+	struct isp1301 *isp = i2c_get_clientdata(client);
+
+	usb_remove_phy(&isp->phy);
+	isp1301_i2c_client = NULL;
+}
+
+static struct i2c_driver isp1301_driver = {
+	.driver = {
+		.name = DRV_NAME,
+		.of_match_table = isp1301_of_match,
+	},
+	.probe = isp1301_probe,
+	.remove = isp1301_remove,
+	.id_table = isp1301_id,
+};
+
+module_i2c_driver(isp1301_driver);
+
+struct i2c_client *isp1301_get_client(struct device_node *node)
+{
+	struct i2c_client *client;
+
+	/* reference of ISP1301 I2C node via DT */
+	client = of_find_i2c_device_by_node(node);
+	if (client)
+		return client;
+
+	/* non-DT: only one ISP1301 chip supported */
+	if (isp1301_i2c_client) {
+		get_device(&isp1301_i2c_client->dev);
+		return isp1301_i2c_client;
+	}
+
+	return NULL;
+}
+EXPORT_SYMBOL_GPL(isp1301_get_client);
+
+MODULE_AUTHOR("Roland Stigge <stigge@antcom.de>");
+MODULE_DESCRIPTION("NXP ISP1301 USB transceiver driver");
+MODULE_LICENSE("GPL");