On 2016/6/9 1:00, Yury Norov wrote:
On Wed, Jun 08, 2016 at 09:34:09AM +0800, zhouchengming wrote:
On 2016/5/24 8:04, Yury Norov wrote:
Here new aarch32 ptrace syscall handler is introsuced to avoid run-time
detection of the task type.
Signed-off-by: Yury Norov<ynorov@xxxxxxxxxxxxxxxxxx>
[...]
Hello, I found ilp32 will use sys_ptrace, not compat_sys_ptrace. So I write
a little patch to see if can solve the problem correctly.
Thanks.
From f6156236df578bb05c4a17e7f9776ceaf8f7afe6 Mon Sep 17 00:00:00 2001
From: Zhou Chengming<zhouchengming1@xxxxxxxxxx>
Date: Wed, 8 Jun 2016 09:46:23 +0800
Subject: [PATCH] ilp32: use compat_sys_ptrace instead of sys_ptrace
When we analyze a testcase of ptrace that failed on ilp32, we found
the syscall that the ilp32 uses is sys_ptrace, not compat_sys_ptrace.
Because in include/uapi/asm-generic/unistd.h it's defined like:
__SYSCALL(__NR_ptrace, sys_ptrace)
So we change it to __SC_COMP(__NR_ptrace, sys_ptrace, compat_sys_ptrace),
let compat tasks use the compat_sys_ptrace.
Signed-off-by: Zhou Chengming<zhouchengming1@xxxxxxxxxx>
---
include/uapi/asm-generic/unistd.h | 2 +-
1 files changed, 1 insertions(+), 1 deletions(-)
diff --git a/include/uapi/asm-generic/unistd.h
b/include/uapi/asm-generic/unistd.h
index 2862d2e..50ee770 100644
--- a/include/uapi/asm-generic/unistd.h
+++ b/include/uapi/asm-generic/unistd.h
@@ -364,7 +364,7 @@ __SC_WRAP(__NR_syslog, sys_syslog)
/* kernel/ptrace.c */
#define __NR_ptrace 117
-__SYSCALL(__NR_ptrace, sys_ptrace)
+__SC_COMP(__NR_ptrace, sys_ptrace, compat_sys_ptrace)
/* kernel/sched/core.c */
#define __NR_sched_setparam 118
--
1.7.7
Hi Zhou,
Thank you for the catch.
Could you also show the test that is failed for you. It should
probably be sent to LTP maillist.
I'm not sure your fix correct as it affects other architectures that
use standard unistd.h. I think it's better to redirect the syscall in
arch/arm64/kernel/sys_ilp32.c with corresponding definition.
Yury
.
Sorry, I missed this mail. Thanks for your reply. :)
I attach the testcase file of ptrace that failed on ilp32.
I also think it's better to redirect the syscall in ilp32, so I changed
the patch.
From 7e692ba1adf02c2a2f125836f5222f455c9ffe56 Mon Sep 17 00:00:00 2001
From: Zhou Chengming <zhouchengming1@xxxxxxxxxx>
Date: Sat, 25 Jun 2016 18:02:51 +0800
Subject: [PATCH] ilp32 should use compat_sys_ptrace
The file include/uapi/asm-generic/unistd.h defines this:
__SYSCALL(__NR_ptrace, sys_ptrace)
It may cause some ptrace tests failed on ilp32. So we redirect the ptrace
syscall in arch/arm64/kernel/sys_ilp32.c with corresponding definition.
Signed-off-by: Zhou Chengming <zhouchengming1@xxxxxxxxxx>
---
arch/arm64/kernel/sys_ilp32.c | 3 +++
1 files changed, 3 insertions(+), 0 deletions(-)
diff --git a/arch/arm64/kernel/sys_ilp32.c b/arch/arm64/kernel/sys_ilp32.c
index d85fe94..06d5e1b 100644
--- a/arch/arm64/kernel/sys_ilp32.c
+++ b/arch/arm64/kernel/sys_ilp32.c
@@ -46,6 +46,9 @@
asmlinkage long ilp32_sys_rt_sigreturn_wrapper(void);
#define compat_sys_rt_sigreturn ilp32_sys_rt_sigreturn_wrapper
+/* ilp32 should use compat_sys_ptrace */
+#define sys_ptrace compat_sys_ptrace
+
#include <asm/syscall.h>
#undef __SYSCALL
--
1.7.7
#include <stdio.h>
#include <stdlib.h>
#include <sys/ptrace.h>
#include <unistd.h>
#include <errno.h>
#include <sys/types.h>
#include <sys/wait.h>
#include <sys/user.h>
#include <signal.h>
int main()
{
pid_t child;
unsigned long exit_status;
int status;
int is_get_event = 0;
long ptrace_ret;
int result = SIGTRAP | (PTRACE_EVENT_EXIT<<8);
child = fork();
if(child < 0)
{
printf("fork error\n");
exit(1);
}
else if(child == 0)
{
sleep(1);
exit(127);
}
else
{
ptrace_ret = ptrace(PTRACE_ATTACH, child, NULL, NULL);
if(ptrace_ret != 0)
{
printf("ptrace PTRACE_ATTACH error %d \n", errno);
exit(1);
}
printf("ATTACH SUCCESS\n");
sleep(1);
ptrace_ret = ptrace(PTRACE_SETOPTIONS, child, NULL, PTRACE_O_TRACEEXIT);
if(ptrace_ret != 0)
{
printf("ptrace PTRACE_SETOPTIONS PTRACE_O_TRACEFORK error %d \n", errno);
ptrace(PTRACE_DETACH, child, NULL, NULL);
exit(1);
}
printf("SETOPTIONS SUCCESS!\n");
while(1)
{
usleep(1);
pid_t pid;
if ((pid = wait(&status)) == -1) {
perror("wait");
exit(1);
};
printf("pid : %d\n", pid);
printf("the child process stops. status: %d, signal? %d, exit? %d, continue? %d, stop? %d\n" , WEXITSTATUS(status) , WIFSIGNALED(status) , WIFEXITED(status) , WIFCONTINUED(status) ,WIFSTOPPED(status));
if (WSTOPSIG(status) == SIGTRAP)
{
printf("status : %d\n", status>>8);
if (status>>8 == result)
{
if (ptrace(PTRACE_GETEVENTMSG, child, NULL, &exit_status))
{
perror("error geteventmsg");
exit(1);
}
printf("exit_status %d\n", WEXITSTATUS((int)exit_status));
exit_status = WEXITSTATUS(exit_status);
if (exit_status != 127)
{
printf("exit status is not equal with 127!\n");
exit(1);
}
is_get_event = 1;
}
}
if (WIFEXITED(status))
{
printf("child exit!\n");
break;
}
if(ptrace(PTRACE_CONT, pid, NULL, (void *) SIGCONT))
{
printf("ptrace cont %d error %d\n", pid, errno);
exit(1);
}
}
if (is_get_event)
exit(0);
else
exit(1);
}
}
