Add a fuzzing engine driver for the sandbox to take inputs from libfuzzer and expose them to the fuzz tests.
Signed-off-by: Andrew Scull ascull@google.com --- arch/Kconfig | 2 ++ arch/sandbox/dts/test.dts | 4 +++ drivers/fuzz/Kconfig | 16 +++++++++--- drivers/fuzz/Makefile | 1 + drivers/fuzz/sandbox_fuzzing_engine.c | 35 +++++++++++++++++++++++++++ 5 files changed, 54 insertions(+), 4 deletions(-) create mode 100644 drivers/fuzz/sandbox_fuzzing_engine.c
diff --git a/arch/Kconfig b/arch/Kconfig index 12de8a1165..8eaf853e4d 100644 --- a/arch/Kconfig +++ b/arch/Kconfig @@ -135,6 +135,7 @@ config SANDBOX select BZIP2 select CMD_POWEROFF select DM + select DM_FUZZING_ENGINE select DM_GPIO select DM_I2C select DM_KEYBOARD @@ -170,6 +171,7 @@ config SANDBOX imply CRC32_VERIFY imply FAT_WRITE imply FIRMWARE + imply FUZZING_ENGINE_SANDBOX imply HASH_VERIFY imply LZMA imply TEE diff --git a/arch/sandbox/dts/test.dts b/arch/sandbox/dts/test.dts index 8f93775ff4..8662017d17 100644 --- a/arch/sandbox/dts/test.dts +++ b/arch/sandbox/dts/test.dts @@ -89,6 +89,10 @@ }; };
+ fuzzing-engine { + compatible = "sandbox,fuzzing-engine"; + }; + reboot-mode0 { compatible = "reboot-mode-gpio"; gpios = <&gpio_c 0 GPIO_ACTIVE_HIGH>, <&gpio_c 1 GPIO_ACTIVE_HIGH>; diff --git a/drivers/fuzz/Kconfig b/drivers/fuzz/Kconfig index a03120f63a..6311385222 100644 --- a/drivers/fuzz/Kconfig +++ b/drivers/fuzz/Kconfig @@ -3,7 +3,15 @@ config DM_FUZZING_ENGINE depends on DM help Enable driver model for fuzzing engine devices. This interface is - used to get successive inputs from a fuzzing engine that aims to - explore different code paths in a fuzz test. The fuzzing engine may - be instrumenting the execution in order to more effectively generate - inputs that explore different code paths. + used to get fuzzing inputs from a fuzzing engine. + +if DM_FUZZING_ENGINE + +config FUZZING_ENGINE_SANDBOX + bool "Sanbox fuzzing engine" + depends on SANDBOX + default y + help + Enable fuzzing engine for sandbox. + +endif diff --git a/drivers/fuzz/Makefile b/drivers/fuzz/Makefile index acd894999c..073743ba94 100644 --- a/drivers/fuzz/Makefile +++ b/drivers/fuzz/Makefile @@ -5,3 +5,4 @@ #
obj-$(CONFIG_DM_FUZZING_ENGINE) += fuzzing_engine-uclass.o +obj-$(CONFIG_FUZZING_ENGINE_SANDBOX) += sandbox_fuzzing_engine.o diff --git a/drivers/fuzz/sandbox_fuzzing_engine.c b/drivers/fuzz/sandbox_fuzzing_engine.c new file mode 100644 index 0000000000..ebb938e5ba --- /dev/null +++ b/drivers/fuzz/sandbox_fuzzing_engine.c @@ -0,0 +1,35 @@ +/* SPDX-License-Identifier: GPL-2.0+ */ +/* + * Copyright (c) 2022 Google, Inc. + * Written by Andrew Scull ascull@google.com + */ + +#include <common.h> +#include <dm.h> +#include <fuzzing_engine.h> +#include <asm/fuzzing_engine.h> + +static int get_input(struct udevice *dev, + const uint8_t **data, + size_t *size) +{ + return sandbox_fuzzing_engine_get_input(data, size); +} + +static const struct dm_fuzzing_engine_ops sandbox_fuzzing_engine_ops = { + .get_input = get_input, +}; + +static const struct udevice_id sandbox_fuzzing_engine_match[] = { + { + .compatible = "sandbox,fuzzing-engine", + }, + {}, +}; + +U_BOOT_DRIVER(sandbox_fuzzing_engine) = { + .name = "sandbox-fuzzing-engine", + .id = UCLASS_FUZZING_ENGINE, + .of_match = sandbox_fuzzing_engine_match, + .ops = &sandbox_fuzzing_engine_ops, +};