Introduce the empty struct ptrace_context, change ptrace_attach_task()
to setup engine->data.
It should be used for ptrace_set_action() and ptrace_set_stop_event(),
the current usage of ->ptrace is racy.
Also, ->exit_code and ->last_siginfo should live in engine->data too.
Eventually, all ptrace-related members should be moved from task_struct.
Note! with this patch every attach means the memory leak, we never
free engine->data. I am not sure how we should free, let's discuss
"[RFC, PATCH] teach utrace to destroy engine->data" first.
---
kernel/ptrace.c | 12 ++++++++++--
1 file changed, 10 insertions(+), 2 deletions(-)
--- PU/kernel/ptrace.c~09_CONTEXT 2009-08-17 16:05:21.000000000 +0200
+++ PU/kernel/ptrace.c 2009-08-17 16:25:12.000000000 +0200
@@ -24,6 +24,8 @@
#include <linux/syscalls.h>
#include <linux/uaccess.h>
+struct ptrace_context {
+};
/*
* ptrace a task: make the debugger its new parent and
@@ -469,17 +471,23 @@ static const struct utrace_engine_ops pt
*/
static int ptrace_attach_task(struct task_struct *tracee)
{
+ struct ptrace_context *context;
struct utrace_engine *engine;
unsigned long events;
+ context = kzalloc(sizeof(*context), GFP_KERNEL);
+ if (unlikely(!context))
+ return -ENOMEM;
+
engine = utrace_attach_task(tracee, UTRACE_ATTACH_CREATE |
UTRACE_ATTACH_EXCLUSIVE |
UTRACE_ATTACH_MATCH_OPS,
- &ptrace_utrace_ops, NULL);
+ &ptrace_utrace_ops, context);
if (unlikely(IS_ERR(engine))) {
int err = PTR_ERR(engine);
if (err != -ESRCH && err != -ERESTARTNOINTR)
- err = -EPERM ;
+ err = -EPERM;
+ kfree(context);
return err;
}
/*
