mirror of
https://github.com/archlinuxarm/PKGBUILDs.git
synced 2024-11-28 22:57:37 +00:00
65 lines
2 KiB
Diff
65 lines
2 KiB
Diff
|
From 596747f36cc455e99f5e6d1b87177e4b208c0c2b Mon Sep 17 00:00:00 2001
|
||
|
From: AKASHI Takahiro <takahiro.akashi@linaro.org>
|
||
|
Date: Thu, 21 Aug 2014 17:56:40 +0900
|
||
|
Subject: [PATCH 11/16] arm64: ptrace: add PTRACE_SET_SYSCALL
|
||
|
|
||
|
To allow tracer to be able to change/skip a system call by re-writing
|
||
|
a syscall number, there are several approaches:
|
||
|
|
||
|
(1) modify x8 register with ptrace(PTRACE_SETREGSET), and handle this case
|
||
|
later on in syscall_trace_enter(), or
|
||
|
(2) support ptrace(PTRACE_SET_SYSCALL) as on arm
|
||
|
|
||
|
Thinking of the fact that user_pt_regs doesn't expose 'syscallno' to
|
||
|
tracer as well as that secure_computing() expects a changed syscall number
|
||
|
to be visible, especially case of -1, before this function returns in
|
||
|
syscall_trace_enter(), we'd better take (2).
|
||
|
|
||
|
Signed-off-by: AKASHI Takahiro <takahiro.akashi@linaro.org>
|
||
|
Reviewed-by: Kees Cook <keescook@chromium.org>
|
||
|
---
|
||
|
arch/arm64/include/uapi/asm/ptrace.h | 1 +
|
||
|
arch/arm64/kernel/ptrace.c | 14 +++++++++++++-
|
||
|
2 files changed, 14 insertions(+), 1 deletion(-)
|
||
|
|
||
|
diff --git a/arch/arm64/include/uapi/asm/ptrace.h b/arch/arm64/include/uapi/asm/ptrace.h
|
||
|
index c136fd53c847..164e2bbe9afd 100644
|
||
|
--- a/arch/arm64/include/uapi/asm/ptrace.h
|
||
|
+++ b/arch/arm64/include/uapi/asm/ptrace.h
|
||
|
@@ -23,6 +23,7 @@
|
||
|
|
||
|
#include <asm/hwcap.h>
|
||
|
|
||
|
+#define PTRACE_SET_SYSCALL 23
|
||
|
|
||
|
/*
|
||
|
* PSR bits
|
||
|
diff --git a/arch/arm64/kernel/ptrace.c b/arch/arm64/kernel/ptrace.c
|
||
|
index 53bdc598d1c1..6ef1e17d9c5b 100644
|
||
|
--- a/arch/arm64/kernel/ptrace.c
|
||
|
+++ b/arch/arm64/kernel/ptrace.c
|
||
|
@@ -1093,7 +1093,19 @@ const struct user_regset_view *task_user_regset_view(struct task_struct *task)
|
||
|
long arch_ptrace(struct task_struct *child, long request,
|
||
|
unsigned long addr, unsigned long data)
|
||
|
{
|
||
|
- return ptrace_request(child, request, addr, data);
|
||
|
+ int ret;
|
||
|
+
|
||
|
+ switch (request) {
|
||
|
+ case PTRACE_SET_SYSCALL:
|
||
|
+ task_pt_regs(child)->syscallno = data;
|
||
|
+ ret = 0;
|
||
|
+ break;
|
||
|
+ default:
|
||
|
+ ret = ptrace_request(child, request, addr, data);
|
||
|
+ break;
|
||
|
+ }
|
||
|
+
|
||
|
+ return ret;
|
||
|
}
|
||
|
|
||
|
enum ptrace_syscall_dir {
|
||
|
--
|
||
|
2.18.0
|
||
|
|