From 6668ed271eaefaa63e686bdfbedaeb7b8e492722 Mon Sep 17 00:00:00 2001 From: Kumar Kartikeya Dwivedi Date: Fri, 4 Sep 2026 10:43:19 +0200 Subject: selftests/bpf: Reject graph kptr use after RCU unlock Add a sleepable verifier test that loads a graph-node local kptr in an explicit RCU read-side critical section, then passes its node to bpf_rbtree_remove() after the section ends. Before the verifier fix, the stale NON_OWN_REF flag makes the node look like a live borrowed reference and the program is accepted. After the fix, the pointer is demoted without NON_OWN_REF and the graph kfunc argument is rejected. Also exercise a graph kptr loaded while a spin lock provides implicit RCU protection. The pointer must be invalidated when the lock is released, which guards the required ordering between non-owning-reference invalidation and RCU demotion. Update the existing fault-protected load test state description. The post-unlock pointer no longer carries NON_OWN_REF, but remains readable because the load is rewritten to use BPF_PROBE_MEM. Signed-off-by: Kumar Kartikeya Dwivedi Link: https://lore.kernel.org/r/20260904084325.52250-7-memxor@gmail.com Signed-off-by: Alexei Starovoitov --- drivers/net/phy/cicada.c | 154 +++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 154 insertions(+) create mode 100644 drivers/net/phy/cicada.c (limited to 'drivers/net/phy/cicada.c') diff --git a/drivers/net/phy/cicada.c b/drivers/net/phy/cicada.c new file mode 100644 index 000000000..d87cf8b94 --- /dev/null +++ b/drivers/net/phy/cicada.c @@ -0,0 +1,154 @@ +// SPDX-License-Identifier: GPL-2.0+ +/* + * drivers/net/phy/cicada.c + * + * Driver for Cicada PHYs + * + * Author: Andy Fleming + * + * Copyright (c) 2004 Freescale Semiconductor, Inc. + */ +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#include +#include +#include + +/* Cicada Extended Control Register 1 */ +#define MII_CIS8201_EXT_CON1 0x17 +#define MII_CIS8201_EXTCON1_INIT 0x0000 + +/* Cicada Interrupt Mask Register */ +#define MII_CIS8201_IMASK 0x19 +#define MII_CIS8201_IMASK_IEN 0x8000 +#define MII_CIS8201_IMASK_SPEED 0x4000 +#define MII_CIS8201_IMASK_LINK 0x2000 +#define MII_CIS8201_IMASK_DUPLEX 0x1000 +#define MII_CIS8201_IMASK_MASK 0xf000 + +/* Cicada Interrupt Status Register */ +#define MII_CIS8201_ISTAT 0x1a +#define MII_CIS8201_ISTAT_STATUS 0x8000 +#define MII_CIS8201_ISTAT_SPEED 0x4000 +#define MII_CIS8201_ISTAT_LINK 0x2000 +#define MII_CIS8201_ISTAT_DUPLEX 0x1000 + +/* Cicada Auxiliary Control/Status Register */ +#define MII_CIS8201_AUX_CONSTAT 0x1c +#define MII_CIS8201_AUXCONSTAT_INIT 0x0004 +#define MII_CIS8201_AUXCONSTAT_DUPLEX 0x0020 +#define MII_CIS8201_AUXCONSTAT_SPEED 0x0018 +#define MII_CIS8201_AUXCONSTAT_GBIT 0x0010 +#define MII_CIS8201_AUXCONSTAT_100 0x0008 + +MODULE_DESCRIPTION("Cicadia PHY driver"); +MODULE_AUTHOR("Andy Fleming"); +MODULE_LICENSE("GPL"); + +static int cis820x_config_init(struct phy_device *phydev) +{ + int err; + + err = phy_write(phydev, MII_CIS8201_AUX_CONSTAT, + MII_CIS8201_AUXCONSTAT_INIT); + + if (err < 0) + return err; + + err = phy_write(phydev, MII_CIS8201_EXT_CON1, + MII_CIS8201_EXTCON1_INIT); + + return err; +} + +static int cis820x_ack_interrupt(struct phy_device *phydev) +{ + int err = phy_read(phydev, MII_CIS8201_ISTAT); + + return (err < 0) ? err : 0; +} + +static int cis820x_config_intr(struct phy_device *phydev) +{ + int err; + + if (phydev->interrupts == PHY_INTERRUPT_ENABLED) { + err = cis820x_ack_interrupt(phydev); + if (err) + return err; + + err = phy_write(phydev, MII_CIS8201_IMASK, + MII_CIS8201_IMASK_MASK); + } else { + err = phy_write(phydev, MII_CIS8201_IMASK, 0); + if (err) + return err; + + err = cis820x_ack_interrupt(phydev); + } + + return err; +} + +static irqreturn_t cis820x_handle_interrupt(struct phy_device *phydev) +{ + int irq_status; + + irq_status = phy_read(phydev, MII_CIS8201_ISTAT); + if (irq_status < 0) { + phy_error(phydev); + return IRQ_NONE; + } + + if (!(irq_status & MII_CIS8201_IMASK_MASK)) + return IRQ_NONE; + + phy_trigger_machine(phydev); + + return IRQ_HANDLED; +} + +/* Cicada 8201, a.k.a Vitesse VSC8201 */ +static struct phy_driver cis820x_driver[] = { +{ + .phy_id = 0x000fc410, + .name = "Cicada Cis8201", + .phy_id_mask = 0x000ffff0, + /* PHY_GBIT_FEATURES */ + .config_init = &cis820x_config_init, + .config_intr = &cis820x_config_intr, + .handle_interrupt = &cis820x_handle_interrupt, +}, { + .phy_id = 0x000fc440, + .name = "Cicada Cis8204", + .phy_id_mask = 0x000fffc0, + /* PHY_GBIT_FEATURES */ + .config_init = &cis820x_config_init, + .config_intr = &cis820x_config_intr, + .handle_interrupt = &cis820x_handle_interrupt, +} }; + +module_phy_driver(cis820x_driver); + +static const struct mdio_device_id __maybe_unused cicada_tbl[] = { + { 0x000fc410, 0x000ffff0 }, + { 0x000fc440, 0x000fffc0 }, + { } +}; + +MODULE_DEVICE_TABLE(mdio, cicada_tbl); -- cgit v1.3.1