Memory safety vulnerability: NULL pointer dereference in ARM FF-A (firmware) bus/driver binding

PoC - Demonstrative kernel-module path that reproduces the vulnerability path on pre-patch kernels: The following kernel module skeleton shows how a NULL-id_table FF-A driver could trigger the vulnerability path prior to this patch. On a system with FF-A support and an FF-A device, loading a driver with a non-NULL probe but without an id_table could cause a NULL-dereference in ffa_device_match when binding the device to the driver. Code (kernel module): #include <linux/module.h> #include <linux/init.h> #include <linux/ffa.h> // Assumes kernel exposes FFA types/functions here static int fake_probe(struct ffa_device *dev) { // Driver would normally handle the device here return 0; } static struct ffa_driver fake_ffa_driver = { .name = "ffa_null_id_driver", .probe = fake_probe, // Note: .id_table intentionally left NULL (or not defined) }; static int __init fake_init(void) { // Registering a driver without an id_table could exercise the vulnerable path return ffa_driver_register(&fake_ffa_driver, THIS_MODULE); } static void __exit fake_exit(void) { ffa_driver_unregister(&fake_ffa_driver); } module_init(fake_init); module_exit(fake_exit); MODULE_LICENSE("GPL"); MODULE_AUTHOR("PoC"); MODULE_DESCRIPTION("PoC for NULL-id_table FF-A driver vulnerability (pre-patch)"); Notes: - This PoC assumes a test environment with ARM FF-A support and an FF-A device present. - On pre-patch kernels, loading this module could trigger a NULL pointer dereference inside ffa_device_match when it accesses id_table->uuid, potentially crashing the kernel. - On patched kernels (post-commit), the guard id_table NULL check prevents dereference, and the module will fail to register due to missing id_table (as intended) without crashing. Prerequisites: - A Linux kernel build/config with FF-A support enabled. - A test machine or VM with ARM architecture compatible with FF-A. - A method to load/unload kernel modules (insmod/rmmod) and a safe test environment (no production systems). If you cannot or should not load kernel modules, you can still verify the vulnerability by static/dynamic analysis comparing pre-patch and post-patch behavior in ffa_device_match and ffa_driver_register with a NULL id_table. The PoC above is provided for completeness in a controlled lab setting.

diff --git a/MAINTAINERS b/MAINTAINERS index 10e8253181d321..750dd4ca3c4259 100644 --- a/MAINTAINERS +++ b/MAINTAINERS @@ -3367,7 +3367,9 @@ F: drivers/irqchip/irq-rda-intc.c F: drivers/tty/serial/rda-uart.c ARM/REALTEK ARCHITECTURE -M: Andreas Färber <afaerber@suse.de> +M: James Tai <james.tai@realtek.com> +M: Yu-Chun Lin <eleanor.lin@realtek.com> +R: Andreas Färber <afaerber@suse.com> L: linux-arm-kernel@lists.infradead.org (moderated for non-subscribers) L: linux-realtek-soc@lists.infradead.org (moderated for non-subscribers) S: Maintained @@ -3375,6 +3377,7 @@ F: Documentation/devicetree/bindings/arm/realtek.yaml F: arch/arm/boot/dts/realtek/ F: arch/arm/mach-realtek/ F: arch/arm64/boot/dts/realtek/ +F: drivers/pinctrl/realtek/ ARM/RISC-V/RENESAS ARCHITECTURE M: Geert Uytterhoeven <geert+renesas@glider.be> diff --git a/arch/arm/boot/dts/renesas/r7s72100-genmai.dts b/arch/arm/boot/dts/renesas/r7s72100-genmai.dts index 3c375650971457..da552a66615e0b 100644 --- a/arch/arm/boot/dts/renesas/r7s72100-genmai.dts +++ b/arch/arm/boot/dts/renesas/r7s72100-genmai.dts @@ -34,9 +34,6 @@ clocks = <&mstp9_clks R7S72100_CLK_SPIBSC0>; power-domains = <&cpg_clocks>; - #address-cells = <1>; - #size-cells = <1>; - partitions { compatible = "fixed-partitions"; #address-cells = <1>; diff --git a/arch/arm/boot/dts/renesas/r7s72100-rskrza1.dts b/arch/arm/boot/dts/renesas/r7s72100-rskrza1.dts index 91178fb9e72102..3306bc9b7bc37b 100644 --- a/arch/arm/boot/dts/renesas/r7s72100-rskrza1.dts +++ b/arch/arm/boot/dts/renesas/r7s72100-rskrza1.dts @@ -36,8 +36,6 @@ power-domains = <&cpg_clocks>; bank-width = <4>; device-width = <1>; - #address-cells = <1>; - #size-cells = <1>; partitions { compatible = "fixed-partitions"; diff --git a/arch/arm/boot/dts/renesas/r7s72100.dtsi b/arch/arm/boot/dts/renesas/r7s72100.dtsi index 245c26bb8e037c..6ec57ffa72e87c 100644 --- a/arch/arm/boot/dts/renesas/r7s72100.dtsi +++ b/arch/arm/boot/dts/renesas/r7s72100.dtsi @@ -37,7 +37,7 @@ clock-div = <3>; }; - bsc: bus { + bsc: bus@0 { compatible = "simple-bus"; #address-cells = <1>; #size-cells = <1>; diff --git a/arch/arm/boot/dts/renesas/r8a7778.dtsi b/arch/arm/boot/dts/renesas/r8a7778.dtsi index 859dd29dfce3bd..7db456b19795dd 100644 --- a/arch/arm/boot/dts/renesas/r8a7778.dtsi +++ b/arch/arm/boot/dts/renesas/r8a7778.dtsi @@ -40,7 +40,7 @@ spi2 = &hspi2; }; - lbsc: bus { + lbsc: bus@0 { compatible = "simple-bus"; #address-cells = <1>; #size-cells = <1>; diff --git a/arch/arm/boot/dts/renesas/r8a7779.dtsi b/arch/arm/boot/dts/renesas/r8a7779.dtsi index e437c22f452dbc..9e8a7e190c89a6 100644 --- a/arch/arm/boot/dts/renesas/r8a7779.dtsi +++ b/arch/arm/boot/dts/renesas/r8a7779.dtsi @@ -704,7 +704,7 @@ }; }; - lbsc: bus { + lbsc: bus@0 { compatible = "simple-bus"; #address-cells = <1>; #size-cells = <1>; diff --git a/arch/arm/boot/dts/renesas/r8a7792.dtsi b/arch/arm/boot/dts/renesas/r8a7792.dtsi index 9e0de69ac3a3a9..fbdbcff1cbed41 100644 --- a/arch/arm/boot/dts/renesas/r8a7792.dtsi +++ b/arch/arm/boot/dts/renesas/r8a7792.dtsi @@ -86,7 +86,7 @@ bootph-all; }; - lbsc: bus { + lbsc: bus@0 { compatible = "simple-bus"; #address-cells = <1>; #size-cells = <1>; diff --git a/arch/arm/mach-versatile/integrator_cp.c b/arch/arm/mach-versatile/integrator_cp.c index 2ed4ded56b3fe0..03dfb5f720b7bd 100644 --- a/arch/arm/mach-versatile/integrator_cp.c +++ b/arch/arm/mach-versatile/integrator_cp.c @@ -86,14 +86,6 @@ static u64 notrace intcp_read_sched_clock(void) return val; } -static void __init intcp_init_early(void) -{ - cm_map = syscon_regmap_lookup_by_compatible("arm,core-module-integrator"); - if (IS_ERR(cm_map)) - return; - sched_clock_register(intcp_read_sched_clock, 32, 24000000); -} - static void __init intcp_init_irq_of(void) { cm_init(); @@ -119,6 +111,10 @@ static void __init intcp_init_of(void) { struct device_node *cpcon; + cm_map = syscon_regmap_lookup_by_compatible("arm,core-module-integrator"); + if (!IS_ERR(cm_map)) + sched_clock_register(intcp_read_sched_clock, 32, 24000000); + cpcon = of_find_matching_node(NULL, intcp_syscon_match); if (!cpcon) return; @@ -138,7 +134,6 @@ static const char * intcp_dt_board_compat[] = { DT_MACHINE_START(INTEGRATOR_CP_DT, "ARM Integrator/CP (Device Tree)") .reserve = integrator_reserve, .map_io = intcp_map_io, - .init_early = intcp_init_early, .init_irq = intcp_init_irq_of, .init_machine = intcp_init_of, .dt_compat = intcp_dt_board_compat, diff --git a/arch/arm64/boot/dts/renesas/draak-ebisu-panel-aa104xd12.dtso b/arch/arm64/boot/dts/renesas/draak-ebisu-panel-aa104xd12.dtso index 258f8668ca3611..90767d74e21b2f 100644 --- a/arch/arm64/boot/dts/renesas/draak-ebisu-panel-aa104xd12.dtso +++ b/arch/arm64/boot/dts/renesas/draak-ebisu-panel-aa104xd12.dtso @@ -27,7 +27,12 @@ status = "okay"; ports { + #address-cells = <1>; + #size-cells = <0>; + port@1 { + reg = <1>; + lvds1_out: endpoint { remote-endpoint = <&panel_in>; }; diff --git a/arch/arm64/boot/dts/renesas/r8a78000.dtsi b/arch/arm64/boot/dts/renesas/r8a78000.dtsi index 3e1c98903cea08..3ec1b53d278282 100644 --- a/arch/arm64/boot/dts/renesas/r8a78000.dtsi +++ b/arch/arm64/boot/dts/renesas/r8a78000.dtsi @@ -699,7 +699,7 @@ "renesas,rcar-gen5-scif", "renesas,scif"; reg = <0 0xc0700000 0 0x40>; interrupts = <GIC_ESPI 10 IRQ_TYPE_LEVEL_HIGH>; - clocks = <&dummy_clk_sgasyncd16>, <&dummy_clk_sgasyncd16>, <&scif_clk>; + clocks = <&dummy_clk_sgasyncd16>, <&dummy_clk_sgasyncd4>, <&scif_clk>; clock-names = "fck", "brg_int", "scif_clk"; status = "disabled"; }; @@ -709,7 +709,7 @@ "renesas,rcar-gen5-scif", "renesas,scif"; reg = <0 0xc0704000 0 0x40>; interrupts = <GIC_ESPI 11 IRQ_TYPE_LEVEL_HIGH>; - clocks = <&dummy_clk_sgasyncd16>, <&dummy_clk_sgasyncd16>, <&scif_clk>; + clocks = <&dummy_clk_sgasyncd16>, <&dummy_clk_sgasyncd4>, <&scif_clk>; clock-names = "fck", "brg_int", "scif_clk"; status = "disabled"; }; @@ -719,7 +719,7 @@ "renesas,rcar-gen5-scif", "renesas,scif"; reg = <0 0xc0708000 0 0x40>; interrupts = <GIC_ESPI 12 IRQ_TYPE_LEVEL_HIGH>; - clocks = <&dummy_clk_sgasyncd16>, <&dummy_clk_sgasyncd16>, <&scif_clk>; + clocks = <&dummy_clk_sgasyncd16>, <&dummy_clk_sgasyncd4>, <&scif_clk>; clock-names = "fck", "brg_int", "scif_clk"; status = "disabled"; }; @@ -729,7 +729,7 @@ "renesas,rcar-gen5-scif", "renesas,scif"; reg = <0 0xc070c000 0 0x40>; interrupts = <GIC_ESPI 13 IRQ_TYPE_LEVEL_HIGH>; - clocks = <&dummy_clk_sgasyncd16>, <&dummy_clk_sgasyncd16>, <&scif_clk>; + clocks = <&dummy_clk_sgasyncd16>, <&dummy_clk_sgasyncd4>, <&scif_clk>; clock-names = "fck", "brg_int", "scif_clk"; status = "disabled"; }; diff --git a/arch/arm64/boot/dts/renesas/r9a09g056.dtsi b/arch/arm64/boot/dts/renesas/r9a09g056.dtsi index 40525470194ec9..7ccddd6a4a9ad8 100644 --- a/arch/arm64/boot/dts/renesas/r9a09g056.dtsi +++ b/arch/arm64/boot/dts/renesas/r9a09g056.dtsi @@ -1327,6 +1327,7 @@ resets = <&cpg 0xaf>; power-domains = <&cpg>; #reset-cells = <0>; + #mux-state-cells = <1>; status = "disabled"; }; diff --git a/arch/arm64/boot/dts/renesas/r9a09g057.dtsi b/arch/arm64/boot/dts/renesas/r9a09g057.dtsi index 9581af58024ede..6f6fe5f36bef38 100644 --- a/arch/arm64/boot/dts/renesas/r9a09g057.dtsi +++ b/arch/arm64/boot/dts/renesas/r9a09g057.dtsi @@ -1345,6 +1345,7 @@ resets = <&cpg 0xaf>; power-domains = <&cpg>; #reset-cells = <0>; + #mux-state-cells = <1>; status = "disabled"; }; @@ -1355,6 +1356,7 @@ resets = <&cpg 0xaf>; power-domains = <&cpg>; #reset-cells = <0>; + #mux-state-cells = <1>; status = "disabled"; }; diff --git a/arch/arm64/boot/dts/renesas/rz-smarc-cru-csi-ov5645.dtsi b/arch/arm64/boot/dts/renesas/rz-smarc-cru-csi-ov5645.dtsi index 4d2b0655859ab4..3feffa4f16a9ac 100644 --- a/arch/arm64/boot/dts/renesas/rz-smarc-cru-csi-ov5645.dtsi +++ b/arch/arm64/boot/dts/renesas/rz-smarc-cru-csi-ov5645.dtsi @@ -46,7 +46,12 @@ status = "okay"; ports { + #address-cells = <1>; + #size-cells = <0>; + port@0 { + reg = <0>; + csi2_in: endpoint { clock-lanes = <0>; data-lanes = <1 2>; diff --git a/arch/arm64/boot/dts/renesas/rz-smarc-du-adv7513.dtsi b/arch/arm64/boot/dts/renesas/rz-smarc-du-adv7513.dtsi index 36707576030d40..f5412578ee65f7 100644 --- a/arch/arm64/boot/dts/renesas/rz-smarc-du-adv7513.dtsi +++ b/arch/arm64/boot/dts/renesas/rz-smarc-du-adv7513.dtsi @@ -26,7 +26,12 @@ status = "okay"; ports { + #address-cells = <1>; + #size-cells = <0>; + port@0 { + reg = <0>; + du_out_rgb: endpoint { remote-endpoint = <&adv7513_in>; }; diff --git a/arch/arm64/boot/dts/renesas/salvator-panel-aa104xd12.dtso b/arch/arm64/boot/dts/renesas/salvator-panel-aa104xd12.dtso index c83a30adc6adf3..7807c3f80409a9 100644 --- a/arch/arm64/boot/dts/renesas/salvator-panel-aa104xd12.dtso +++ b/arch/arm64/boot/dts/renesas/salvator-panel-aa104xd12.dtso @@ -27,7 +27,12 @@ status = "okay"; ports { + #address-cells = <1>; + #size-cells = <0>; + port@1 { + reg = <1>; + lvds0_out: endpoint { remote-endpoint = <&panel_in>; }; diff --git a/arch/riscv/boot/dts/microchip/mpfs-icicle-kit-fabric.dtsi b/arch/riscv/boot/dts/microchip/mpfs-icicle-kit-fabric.dtsi index 2d14e92f068d56..9078e5b1e49c19 100644 --- a/arch/riscv/boot/dts/microchip/mpfs-icicle-kit-fabric.dtsi +++ b/arch/riscv/boot/dts/microchip/mpfs-icicle-kit-fabric.dtsi @@ -101,16 +101,6 @@ status = "okay"; }; -&i2c0 { - pinctrl-names = "default"; - pinctrl-0 = <&i2c0_fabric>; -}; - -&i2c1 { - pinctrl-names = "default"; - pinctrl-0 = <&i2c1_mssio>; -}; - &mmuart1 { pinctrl-names = "default"; pinctrl-0 = <&uart1_fabric>; diff --git a/arch/riscv/boot/dts/microchip/mpfs-icicle-kit-prod.dts b/arch/riscv/boot/dts/microchip/mpfs-icicle-kit-prod.dts index 8afedece89d1f1..636493f6584d20 100644 --- a/arch/riscv/boot/dts/microchip/mpfs-icicle-kit-prod.dts +++ b/arch/riscv/boot/dts/microchip/mpfs-icicle-kit-prod.dts @@ -14,6 +14,16 @@ "microchip,mpfs"; }; +&i2c0 { + pinctrl-names = "default"; + pinctrl-0 = <&i2c0_fabric>; +}; + +&i2c1 { + pinctrl-names = "default"; + pinctrl-0 = <&i2c1_mssio>; +}; + &syscontroller { microchip,bitstream-flash = <&sys_ctrl_flash>; }; diff --git a/arch/riscv/boot/dts/microchip/mpfs-icicle-kit.dts b/arch/riscv/boot/dts/microchip/mpfs-icicle-kit.dts index 556aa9638282e2..6fadce815c9a26 100644 --- a/arch/riscv/boot/dts/microchip/mpfs-icicle-kit.dts +++ b/arch/riscv/boot/dts/microchip/mpfs-icicle-kit.dts @@ -11,3 +11,22 @@ "microchip,mpfs-icicle-kit", "microchip,mpfs"; }; + +&i2c0 { + pinctrl-names = "default"; + pinctrl-0 = <&i2c0_fabric>; +}; + +/* + * Due to silicon errata, routing via MSS IOs doesn't work on ES devices. + * Instead, i2c1, appearing on B1/C1, which are normally MSS IOs, is routed + * via the fabric and back to B1/C1 via "fabric-test" functionality. + * This is done silently by Libero, so the iomux0 setting for i2c1 has to + * be fabric IO, despite tooling etc saying that MSS IOs are used. + * + * See Section 3.3 of https://ww1.microchip.com/downloads/aemDocuments/documents/FPGA/ProductDocuments/Errata/polarfiresoc/microsemi_polarfire_soc_fpga_egineering_samples_errata_er0219_v1.pdf + */ +&i2c1 { + pinctrl-names = "default"; + pinctrl-0 = <&i2c1_fabric>; +}; diff --git a/arch/riscv/boot/dts/starfive/jh7110-common.dtsi b/arch/riscv/boot/dts/starfive/jh7110-common.dtsi index 8cfe8033305d80..a7a1c09a2c9075 100644 --- a/arch/riscv/boot/dts/starfive/jh7110-common.dtsi +++ b/arch/riscv/boot/dts/starfive/jh7110-common.dtsi @@ -135,29 +135,6 @@ clock-frequency = <49152000>; }; -&camss { - assigned-clocks = <&ispcrg JH7110_ISPCLK_DOM4_APB_FUNC>, - <&ispcrg JH7110_ISPCLK_MIPI_RX0_PXL>; - assigned-clock-rates = <49500000>, <198000000>; - - ports { - #address-cells = <1>; - #size-cells = <0>; - - port@0 { - reg = <0>; - }; - - port@1 { - reg = <1>; - - camss_from_csi2rx: endpoint { - remote-endpoint = <&csi2rx_to_camss>; - }; - }; - }; -}; - &csi2rx { assigned-clocks = <&ispcrg JH7110_ISPCLK_VIN_SYS>; assigned-clock-rates = <297000000>; @@ -175,9 +152,7 @@ port@1 { reg = <1>; - csi2rx_to_camss: endpoint { - remote-endpoint = <&camss_from_csi2rx>; - }; + /* remote CAMSS endpoint */ }; }; }; diff --git a/arch/riscv/boot/dts/starfive/jh7110.dtsi b/arch/riscv/boot/dts/starfive/jh7110.dtsi index 6e56e9d20bb064..9c3e4598747eb5 100644 --- a/arch/riscv/boot/dts/starfive/jh7110.dtsi +++ b/arch/riscv/boot/dts/starfive/jh7110.dtsi @@ -1199,34 +1199,6 @@ #phy-cells = <0>; }; - camss: isp@19840000 { - compatible = "starfive,jh7110-camss"; - reg = <0x0 0x19840000 0x0 0x10000>, - <0x0 0x19870000 0x0 0x30000>; - reg-names = "syscon", "isp"; - clocks = <&ispcrg JH7110_ISPCLK_DOM4_APB_FUNC>, - <&ispcrg JH7110_ISPCLK_ISPV2_TOP_WRAPPER_C>, - <&ispcrg JH7110_ISPCLK_DVP_INV>, - <&ispcrg JH7110_ISPCLK_VIN_P_AXI_WR>, - <&ispcrg JH7110_ISPCLK_MIPI_RX0_PXL>, - <&syscrg JH7110_SYSCLK_ISP_TOP_CORE>, - <&syscrg JH7110_SYSCLK_ISP_TOP_AXI>; - clock-names = "apb_func", "wrapper_clk_c", "dvp_inv", - "axiwr", "mipi_rx0_pxl", "ispcore_2x", - "isp_axi"; - resets = <&ispcrg JH7110_ISPRST_ISPV2_TOP_WRAPPER_P>, - <&ispcrg JH7110_ISPRST_ISPV2_TOP_WRAPPER_C>, - <&ispcrg JH7110_ISPRST_VIN_P_AXI_RD>, - <&ispcrg JH7110_ISPRST_VIN_P_AXI_WR>, - <&syscrg JH7110_SYSRST_ISP_TOP>, - <&syscrg JH7110_SYSRST_ISP_TOP_AXI>; - reset-names = "wrapper_p", "wrapper_c", "axird", - "axiwr", "isp_top_n", "isp_top_axi"; - power-domains = <&pwrc JH7110_PD_ISP>; - interrupts = <92>, <87>, <90>, <88>; - status = "disabled"; - }; - voutcrg: clock-controller@295c0000 { compatible = "starfive,jh7110-voutcrg"; reg = <0x0 0x295c0000 0x0 0x10000>; diff --git a/drivers/firmware/arm_ffa/bus.c b/drivers/firmware/arm_ffa/bus.c index 9576862d89c40c..601c3418e0d927 100644 --- a/drivers/firmware/arm_ffa/bus.c +++ b/drivers/firmware/arm_ffa/bus.c @@ -26,6 +26,8 @@ static int ffa_device_match(struct device *dev, const struct device_driver *drv) id_table = to_ffa_driver(drv)->id_table; ffa_dev = to_ffa_dev(dev); + if (!id_table) + return 0; while (!uuid_is_null(&id_table->uuid)) { /* @@ -123,7 +125,7 @@ int ffa_driver_register(struct ffa_driver *driver, struct module *owner, { int ret; - if (!driver->probe) + if (!driver->probe || !driver->id_table) return -EINVAL; driver->driver.bus = &ffa_bus_type; diff --git a/drivers/firmware/arm_ffa/driver.c b/drivers/firmware/arm_ffa/driver.c index eb278284828376..b9f17fda724327 100644 --- a/drivers/firmware/arm_ffa/driver.c +++ b/drivers/firmware/arm_ffa/driver.c @@ -87,6 +87,7 @@ static inline int ffa_to_l ... [truncated]