From 33a154a96e71a34a1bcca9f40da343dbbf7b38b4 Mon Sep 17 00:00:00 2001 From: Alexei Starovoitov Date: Thu, 1 Oct 2026 14:52:55 +0000 Subject: selftests/bpf: Test packet range of pointers sharing an id 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 Link: https://lore.kernel.org/bpf/20261001145255.855630-2-alexei.starovoitov@gmail.com Signed-off-by: Kumar Kartikeya Dwivedi --- drivers/dio/dio-driver.c | 142 +++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 142 insertions(+) create mode 100644 drivers/dio/dio-driver.c (limited to 'drivers/dio/dio-driver.c') diff --git a/drivers/dio/dio-driver.c b/drivers/dio/dio-driver.c new file mode 100644 index 000000000..12fa2d209 --- /dev/null +++ b/drivers/dio/dio-driver.c @@ -0,0 +1,142 @@ +/* + * DIO Driver Services + * + * Copyright (C) 2004 Jochen Friedrich + * + * Loosely based on drivers/pci/pci-driver.c and drivers/zorro/zorro-driver.c + * + * This file is subject to the terms and conditions of the GNU General Public + * License. See the file COPYING in the main directory of this archive + * for more details. + */ + +#include +#include +#include + + +/** + * dio_match_device - Tell if a DIO device structure has a matching DIO device id structure + * @ids: array of DIO device id structures to search in + * @d: the DIO device structure to match against + * + * Used by a driver to check whether a DIO device present in the + * system is in its list of supported devices. Returns the matching + * dio_device_id structure or %NULL if there is no match. + */ + +static const struct dio_device_id * +dio_match_device(const struct dio_device_id *ids, + const struct dio_dev *d) +{ + while (ids->id) { + if (ids->id == DIO_WILDCARD) + return ids; + if (DIO_NEEDSSECID(ids->id & 0xff)) { + if (ids->id == d->id) + return ids; + } else { + if ((ids->id & 0xff) == (d->id & 0xff)) + return ids; + } + ids++; + } + return NULL; +} + +static int dio_device_probe(struct device *dev) +{ + int error = 0; + struct dio_driver *drv = to_dio_driver(dev->driver); + struct dio_dev *d = to_dio_dev(dev); + + if (!d->driver && drv->probe) { + const struct dio_device_id *id; + + id = dio_match_device(drv->id_table, d); + if (id) + error = drv->probe(d, id); + if (error >= 0) { + d->driver = drv; + error = 0; + } + } + return error; +} + + +/** + * dio_register_driver - register a new DIO driver + * @drv: the driver structure to register + * + * Adds the driver structure to the list of registered drivers + * Returns zero or a negative error value. + */ + +int dio_register_driver(struct dio_driver *drv) +{ + /* initialize common driver fields */ + drv->driver.name = drv->name; + drv->driver.bus = &dio_bus_type; + + /* register with core */ + return driver_register(&drv->driver); +} + + +/** + * dio_unregister_driver - unregister a DIO driver + * @drv: the driver structure to unregister + * + * Deletes the driver structure from the list of registered DIO drivers, + * gives it a chance to clean up by calling its remove() function for + * each device it was responsible for, and marks those devices as + * driverless. + */ + +void dio_unregister_driver(struct dio_driver *drv) +{ + driver_unregister(&drv->driver); +} + + +/** + * dio_bus_match - Tell if a DIO device structure has a matching DIO device id structure + * @dev: the DIO device structure to match against + * @drv: the &device_driver that points to the array of DIO device id structures to search + * + * Used by the driver core to check whether a DIO device present in the + * system is in a driver's list of supported devices. Returns 1 if supported, + * and 0 if there is no match. + */ + +static int dio_bus_match(struct device *dev, const struct device_driver *drv) +{ + struct dio_dev *d = to_dio_dev(dev); + const struct dio_driver *dio_drv = to_dio_driver(drv); + const struct dio_device_id *ids = dio_drv->id_table; + + if (!ids) + return 0; + + return dio_match_device(ids, d) ? 1 : 0; +} + + +const struct bus_type dio_bus_type = { + .name = "dio", + .match = dio_bus_match, + .probe = dio_device_probe, +}; + + +static int __init dio_driver_init(void) +{ + return bus_register(&dio_bus_type); +} + +postcore_initcall(dio_driver_init); + +EXPORT_SYMBOL(dio_register_driver); +EXPORT_SYMBOL(dio_unregister_driver); +EXPORT_SYMBOL(dio_bus_type); -- cgit v1.3.1