diff options
| -rw-r--r-- | arch/arm64/include/asm/ftrace.h | 11 | ||||
| -rw-r--r-- | arch/arm64/include/asm/stacktrace.h | 6 | ||||
| -rw-r--r-- | arch/arm64/kernel/ftrace.c | 6 | ||||
| -rw-r--r-- | arch/arm64/kernel/stacktrace.c | 18 |
4 files changed, 22 insertions, 19 deletions
diff --git a/arch/arm64/include/asm/ftrace.h b/arch/arm64/include/asm/ftrace.h index 347b0cc68f07..1494cfa8639b 100644 --- a/arch/arm64/include/asm/ftrace.h +++ b/arch/arm64/include/asm/ftrace.h @@ -12,6 +12,17 @@ #define HAVE_FUNCTION_GRAPH_FP_TEST +/* + * HAVE_FUNCTION_GRAPH_RET_ADDR_PTR means that the architecture can provide a + * "return address pointer" which can be used to uniquely identify a return + * address which has been overwritten. + * + * On arm64 we use the address of the caller's frame record, which remains the + * same for the lifetime of the instrumented function, unlike the return + * address in the LR. + */ +#define HAVE_FUNCTION_GRAPH_RET_ADDR_PTR + #ifdef CONFIG_DYNAMIC_FTRACE_WITH_REGS #define ARCH_SUPPORTS_FTRACE_OPS 1 #else diff --git a/arch/arm64/include/asm/stacktrace.h b/arch/arm64/include/asm/stacktrace.h index a4e046ef4568..6564a01cc085 100644 --- a/arch/arm64/include/asm/stacktrace.h +++ b/arch/arm64/include/asm/stacktrace.h @@ -47,9 +47,6 @@ struct stack_info { * @prev_type: The type of stack this frame record was on, or a synthetic * value of STACK_TYPE_UNKNOWN. This is used to detect a * transition from one stack to another. - * - * @graph: When FUNCTION_GRAPH_TRACER is selected, holds the index of a - * replacement lr value in the ftrace graph stack. */ struct stackframe { unsigned long fp; @@ -57,9 +54,6 @@ struct stackframe { DECLARE_BITMAP(stacks_done, __NR_STACK_TYPES); unsigned long prev_fp; enum stack_type prev_type; -#ifdef CONFIG_FUNCTION_GRAPH_TRACER - int graph; -#endif #ifdef CONFIG_KRETPROBES struct llist_node *kr_cur; #endif diff --git a/arch/arm64/kernel/ftrace.c b/arch/arm64/kernel/ftrace.c index fc62dfe73f93..4506c4a90ac1 100644 --- a/arch/arm64/kernel/ftrace.c +++ b/arch/arm64/kernel/ftrace.c @@ -244,8 +244,6 @@ void arch_ftrace_update_code(int command) * on the way back to parent. For this purpose, this function is called * in _mcount() or ftrace_caller() to replace return address (*parent) on * the call stack to return_to_handler. - * - * Note that @frame_pointer is used only for sanity check later. */ void prepare_ftrace_return(unsigned long self_addr, unsigned long *parent, unsigned long frame_pointer) @@ -263,8 +261,10 @@ void prepare_ftrace_return(unsigned long self_addr, unsigned long *parent, */ old = *parent; - if (!function_graph_enter(old, self_addr, frame_pointer, NULL)) + if (!function_graph_enter(old, self_addr, frame_pointer, + (void *)frame_pointer)) { *parent = return_hooker; + } } #ifdef CONFIG_DYNAMIC_FTRACE diff --git a/arch/arm64/kernel/stacktrace.c b/arch/arm64/kernel/stacktrace.c index c30624fff6ac..94f83cd44e50 100644 --- a/arch/arm64/kernel/stacktrace.c +++ b/arch/arm64/kernel/stacktrace.c @@ -38,9 +38,6 @@ void start_backtrace(struct stackframe *frame, unsigned long fp, { frame->fp = fp; frame->pc = pc; -#ifdef CONFIG_FUNCTION_GRAPH_TRACER - frame->graph = 0; -#endif #ifdef CONFIG_KRETPROBES frame->kr_cur = NULL; #endif @@ -116,20 +113,23 @@ int notrace unwind_frame(struct task_struct *tsk, struct stackframe *frame) frame->prev_fp = fp; frame->prev_type = info.type; + frame->pc = ptrauth_strip_insn_pac(frame->pc); + #ifdef CONFIG_FUNCTION_GRAPH_TRACER if (tsk->ret_stack && - (ptrauth_strip_insn_pac(frame->pc) == (unsigned long)return_to_handler)) { - struct ftrace_ret_stack *ret_stack; + (frame->pc == (unsigned long)return_to_handler)) { + unsigned long orig_pc; /* * This is a case where function graph tracer has * modified a return address (LR) in a stack frame * to hook a function return. * So replace it to an original value. */ - ret_stack = ftrace_graph_get_ret_stack(tsk, frame->graph++); - if (WARN_ON_ONCE(!ret_stack)) + orig_pc = ftrace_graph_ret_addr(tsk, NULL, frame->pc, + (void *)frame->fp); + if (WARN_ON_ONCE(frame->pc == orig_pc)) return -EINVAL; - frame->pc = ret_stack->ret; + frame->pc = orig_pc; } #endif /* CONFIG_FUNCTION_GRAPH_TRACER */ #ifdef CONFIG_KRETPROBES @@ -137,8 +137,6 @@ int notrace unwind_frame(struct task_struct *tsk, struct stackframe *frame) frame->pc = kretprobe_find_ret_addr(tsk, (void *)frame->fp, &frame->kr_cur); #endif - frame->pc = ptrauth_strip_insn_pac(frame->pc); - return 0; } NOKPROBE_SYMBOL(unwind_frame); |