diff options
| author | Guo Ren <guoren@linux.alibaba.com> | 2020-12-17 16:01:45 +0000 |
|---|---|---|
| committer | Palmer Dabbelt <palmerdabbelt@google.com> | 2021-01-14 15:09:09 -0800 |
| commit | ee55ff803b383e03d0855661d3416aa1763e54f9 (patch) | |
| tree | 68784ade3682f8fdec69c72497155dee098fc83d | |
| parent | 74784081aac8a0f3636965fc230e2d3b7cc123c6 (diff) | |
riscv: Add support for function error injection
Inspired by the commit 42d038c4fb00 ("arm64: Add support for function
error injection"), this patch supports function error injection for
riscv.
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.
Test log:
cd /sys/kernel/debug/fail_function
echo sys_clone > inject
echo 100 > probability
echo 1 > interval
ls /
[ 313.176875] FAULT_INJECTION: forcing a failure.
[ 313.176875] name fail_function, interval 1, probability 100, space 0, times 1
[ 313.184357] CPU: 0 PID: 87 Comm: sh Not tainted 5.8.0-rc5-00007-g6a758cc #117
[ 313.187616] Call Trace:
[ 313.189100] [<ffffffe0002036b6>] walk_stackframe+0x0/0xc2
[ 313.191626] [<ffffffe00020395c>] show_stack+0x40/0x4c
[ 313.193927] [<ffffffe000556c60>] dump_stack+0x7c/0x96
[ 313.194795] [<ffffffe0005522e8>] should_fail+0x140/0x142
[ 313.195923] [<ffffffe000299ffc>] fei_kprobe_handler+0x2c/0x5a
[ 313.197687] [<ffffffe0009e2ec4>] kprobe_breakpoint_handler+0xb4/0x18a
[ 313.200054] [<ffffffe00020357e>] do_trap_break+0x36/0xca
[ 313.202147] [<ffffffe000201bca>] ret_from_exception+0x0/0xc
[ 313.204556] [<ffffffe000201bbc>] ret_from_syscall+0x0/0x2
-sh: can't fork: Invalid argument
Signed-off-by: Guo Ren <guoren@linux.alibaba.com>
Reviewed-by: Masami Hiramatsu <mhiramat@kernel.org>
Cc: Palmer Dabbelt <palmerdabbelt@google.com>
Cc: Paul Walmsley <paul.walmsley@sifive.com>
Signed-off-by: Palmer Dabbelt <palmerdabbelt@google.com>
| -rw-r--r-- | arch/riscv/Kconfig | 1 | ||||
| -rw-r--r-- | arch/riscv/include/asm/ptrace.h | 6 | ||||
| -rw-r--r-- | arch/riscv/lib/Makefile | 2 | ||||
| -rw-r--r-- | arch/riscv/lib/error-inject.c | 10 |
4 files changed, 19 insertions, 0 deletions
diff --git a/arch/riscv/Kconfig b/arch/riscv/Kconfig index 7b5bb48055e7..18d293f84318 100644 --- a/arch/riscv/Kconfig +++ b/arch/riscv/Kconfig @@ -67,6 +67,7 @@ config RISCV select HAVE_DEBUG_KMEMLEAK select HAVE_DMA_CONTIGUOUS if MMU select HAVE_EBPF_JIT if MMU + select HAVE_FUNCTION_ERROR_INJECTION select HAVE_FUTEX_CMPXCHG if FUTEX select HAVE_GCC_PLUGINS select HAVE_GENERIC_VDSO if MMU && 64BIT diff --git a/arch/riscv/include/asm/ptrace.h b/arch/riscv/include/asm/ptrace.h index 23372bbcfde8..cb4abb639e8d 100644 --- a/arch/riscv/include/asm/ptrace.h +++ b/arch/riscv/include/asm/ptrace.h @@ -109,6 +109,12 @@ static inline unsigned long regs_return_value(struct pt_regs *regs) return regs->a0; } +static inline void regs_set_return_value(struct pt_regs *regs, + unsigned long val) +{ + regs->a0 = val; +} + extern int regs_query_register_offset(const char *name); extern unsigned long regs_get_kernel_stack_nth(struct pt_regs *regs, unsigned int n); diff --git a/arch/riscv/lib/Makefile b/arch/riscv/lib/Makefile index ac6171e9c19e..25d5c9664e57 100644 --- a/arch/riscv/lib/Makefile +++ b/arch/riscv/lib/Makefile @@ -5,3 +5,5 @@ lib-y += memset.o lib-y += memmove.o lib-$(CONFIG_MMU) += uaccess.o lib-$(CONFIG_64BIT) += tishift.o + +obj-$(CONFIG_FUNCTION_ERROR_INJECTION) += error-inject.o diff --git a/arch/riscv/lib/error-inject.c b/arch/riscv/lib/error-inject.c new file mode 100644 index 000000000000..d667ade2bc41 --- /dev/null +++ b/arch/riscv/lib/error-inject.c @@ -0,0 +1,10 @@ +// SPDX-License-Identifier: GPL-2.0 + +#include <linux/error-injection.h> +#include <linux/kprobes.h> + +void override_function_with_return(struct pt_regs *regs) +{ + instruction_pointer_set(regs, regs->ra); +} +NOKPROBE_SYMBOL(override_function_with_return); |