diff options
| author | Leo Yan <leo.yan@linaro.org> | 2019-08-06 18:00:14 +0800 |
|---|---|---|
| committer | Will Deacon <will@kernel.org> | 2019-08-07 13:53:09 +0100 |
| commit | 42d038c4fb00f1ec1a4c4616784da4561385b628 (patch) | |
| tree | c8c5335e01986c073ae56ca1df94eeed5c13fe1e /arch/arm64 | |
| parent | 45880f7b7b19e043ce0aaa4cb7d05369425c82fa (diff) | |
arm64: Add support for function error injection
Inspired by the commit 7cd01b08d35f ("powerpc: Add support for function
error injection"), this patch supports function error injection for
Arm64.
This patch mainly support two functions: one is regs_set_return_value()
which is used to overwrite the return value; the another function is
override_function_with_return() which is to override the probed
function returning and jump to its caller.
Reviewed-by: Masami Hiramatsu <mhiramat@kernel.org>
Signed-off-by: Leo Yan <leo.yan@linaro.org>
Signed-off-by: Will Deacon <will@kernel.org>
Diffstat (limited to 'arch/arm64')
| -rw-r--r-- | arch/arm64/Kconfig | 1 | ||||
| -rw-r--r-- | arch/arm64/include/asm/ptrace.h | 5 | ||||
| -rw-r--r-- | arch/arm64/lib/Makefile | 2 | ||||
| -rw-r--r-- | arch/arm64/lib/error-inject.c | 18 |
4 files changed, 26 insertions, 0 deletions
diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig index 3adcec05b1f6..b15803afb2a0 100644 --- a/arch/arm64/Kconfig +++ b/arch/arm64/Kconfig @@ -148,6 +148,7 @@ config ARM64 select HAVE_FAST_GUP select HAVE_FTRACE_MCOUNT_RECORD select HAVE_FUNCTION_TRACER + select HAVE_FUNCTION_ERROR_INJECTION select HAVE_FUNCTION_GRAPH_TRACER select HAVE_GCC_PLUGINS select HAVE_HW_BREAKPOINT if PERF_EVENTS diff --git a/arch/arm64/include/asm/ptrace.h b/arch/arm64/include/asm/ptrace.h index 1dcf63a9ac1f..fbebb411ae20 100644 --- a/arch/arm64/include/asm/ptrace.h +++ b/arch/arm64/include/asm/ptrace.h @@ -301,6 +301,11 @@ static inline unsigned long regs_return_value(struct pt_regs *regs) return regs->regs[0]; } +static inline void regs_set_return_value(struct pt_regs *regs, unsigned long rc) +{ + regs->regs[0] = rc; +} + /** * regs_get_kernel_argument() - get Nth function argument in kernel * @regs: pt_regs of that context diff --git a/arch/arm64/lib/Makefile b/arch/arm64/lib/Makefile index 33c2a4abda04..f182ccb0438e 100644 --- a/arch/arm64/lib/Makefile +++ b/arch/arm64/lib/Makefile @@ -33,3 +33,5 @@ UBSAN_SANITIZE_atomic_ll_sc.o := n lib-$(CONFIG_ARCH_HAS_UACCESS_FLUSHCACHE) += uaccess_flushcache.o obj-$(CONFIG_CRC32) += crc32.o + +obj-$(CONFIG_FUNCTION_ERROR_INJECTION) += error-inject.o diff --git a/arch/arm64/lib/error-inject.c b/arch/arm64/lib/error-inject.c new file mode 100644 index 000000000000..ed15021da3ed --- /dev/null +++ b/arch/arm64/lib/error-inject.c @@ -0,0 +1,18 @@ +// SPDX-License-Identifier: GPL-2.0 + +#include <linux/error-injection.h> +#include <linux/kprobes.h> + +void override_function_with_return(struct pt_regs *regs) +{ + /* + * 'regs' represents the state on entry of a predefined function in + * the kernel/module and which is captured on a kprobe. + * + * When kprobe returns back from exception it will override the end + * of probed function and directly return to the predefined + * function's caller. + */ + instruction_pointer_set(regs, procedure_link_pointer(regs)); +} +NOKPROBE_SYMBOL(override_function_with_return); |