From e873c74132f0c5f1452816cd9bb26208f0bba1e1 Mon Sep 17 00:00:00 2001 From: Shivank Garg Date: Sat, 22 Aug 2026 19:22:05 +0000 Subject: dmaengine: fix use-after-free in dma_chan_put() and dma_release_channel() When dma_device_put() drops the last reference on chan->device->ref, dma_device_release() runs and may free the dma_device along with its channels. dma_chan_put() then still reads chan->device->owner via dma_chan_to_owner() for the trailing module_put(). KASAN catches it: slab-use-after-free in dma_chan_put+0x3e6/0x4c0 Read of size 8 by task insmod/6319 Freed by task 6319: kfree+0x225/0x470 dma_chan_put+0x395/0x4c0 dmaengine_put+0xf8/0x160 Cache the module owner in dma_chan_put() before the put so the trailing module_put() does not need chan->device. Fixes: 8ad342a86359 ("dmaengine: Add reference counting to dma_device struct") Suggested-by: Sashiko Link: https://sashiko.dev/#/patchset/20260518-dmaengine-kref-fix-v1-1-4d6125048fb7@amd.com Reviewed-by: Frank Li Reviewed-by: Logan Gunthorpe Signed-off-by: Shivank Garg Link: https://patch.msgid.link/20260822-dmaengine-kref-fix-v5-3-d4a4ee47d927@amd.com Signed-off-by: Vinod Koul --- drivers/net/phy/amd.c | 120 ++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 120 insertions(+) create mode 100644 drivers/net/phy/amd.c (limited to 'drivers/net/phy/amd.c') diff --git a/drivers/net/phy/amd.c b/drivers/net/phy/amd.c new file mode 100644 index 000000000..75b5fe655 --- /dev/null +++ b/drivers/net/phy/amd.c @@ -0,0 +1,120 @@ +// SPDX-License-Identifier: GPL-2.0+ +/* + * Driver for AMD am79c PHYs + * + * Author: Heiko Schocher + * + * Copyright (c) 2011 DENX Software Engineering GmbH + */ +#include +#include +#include +#include +#include +#include + +#define PHY_ID_AC101L 0x00225520 +#define PHY_ID_AM79C874 0x0022561b + +#define MII_AM79C_IR 17 /* Interrupt Status/Control Register */ +#define MII_AM79C_IR_EN_LINK 0x0400 /* IR enable Linkstate */ +#define MII_AM79C_IR_EN_ANEG 0x0100 /* IR enable Aneg Complete */ +#define MII_AM79C_IR_IMASK_INIT (MII_AM79C_IR_EN_LINK | MII_AM79C_IR_EN_ANEG) + +#define MII_AM79C_IR_LINK_DOWN BIT(2) +#define MII_AM79C_IR_ANEG_DONE BIT(0) +#define MII_AM79C_IR_IMASK_STAT (MII_AM79C_IR_LINK_DOWN | MII_AM79C_IR_ANEG_DONE) + +MODULE_DESCRIPTION("AMD PHY driver"); +MODULE_AUTHOR("Heiko Schocher "); +MODULE_LICENSE("GPL"); + +static int am79c_ack_interrupt(struct phy_device *phydev) +{ + int err; + + err = phy_read(phydev, MII_BMSR); + if (err < 0) + return err; + + err = phy_read(phydev, MII_AM79C_IR); + if (err < 0) + return err; + + return 0; +} + +static int am79c_config_init(struct phy_device *phydev) +{ + return 0; +} + +static int am79c_config_intr(struct phy_device *phydev) +{ + int err; + + if (phydev->interrupts == PHY_INTERRUPT_ENABLED) { + err = am79c_ack_interrupt(phydev); + if (err) + return err; + + err = phy_write(phydev, MII_AM79C_IR, MII_AM79C_IR_IMASK_INIT); + } else { + err = phy_write(phydev, MII_AM79C_IR, 0); + if (err) + return err; + + err = am79c_ack_interrupt(phydev); + } + + return err; +} + +static irqreturn_t am79c_handle_interrupt(struct phy_device *phydev) +{ + int irq_status; + + irq_status = phy_read(phydev, MII_AM79C_IR); + if (irq_status < 0) { + phy_error(phydev); + return IRQ_NONE; + } + + if (!(irq_status & MII_AM79C_IR_IMASK_STAT)) + return IRQ_NONE; + + phy_trigger_machine(phydev); + + return IRQ_HANDLED; +} + +static struct phy_driver am79c_drivers[] = { + { + .phy_id = PHY_ID_AM79C874, + .name = "AM79C874", + .phy_id_mask = 0xfffffff0, + /* PHY_BASIC_FEATURES */ + .config_init = am79c_config_init, + .config_intr = am79c_config_intr, + .handle_interrupt = am79c_handle_interrupt, + }, + { + .phy_id = PHY_ID_AC101L, + .name = "AC101L", + .phy_id_mask = 0xfffffff0, + /* PHY_BASIC_FEATURES */ + .config_init = am79c_config_init, + .config_intr = am79c_config_intr, + .handle_interrupt = am79c_handle_interrupt, + }, +}; + +module_phy_driver(am79c_drivers); + +static const struct mdio_device_id __maybe_unused amd_tbl[] = { + { PHY_ID_AC101L, 0xfffffff0 }, + { PHY_ID_AM79C874, 0xfffffff0 }, + { } +}; + +MODULE_DEVICE_TABLE(mdio, amd_tbl); -- cgit v1.3.1