Something like this?
This patch:
- adds ptrace_context->sysemu boolean. (it will die)
- changes ptrace_resume() so that SYSEMU/SYSEMU_SINGLESTEP
set context ->sysemu, and require only SYSCALL_ENTRY event,
not UTRACE_EVENT_SYSCALL which includes SYSCALL_EXIT as well.
Afaics, this should handle PTRACE_SYSEMU correctly.
But PTRACE_SYSEMU_SINGLESTEP case is not exactly right, it always sets
action = UTRACE_SINGLESTEP. Looks like, it should be UTRACE_RESUME if
the tracee has stopped somewhere after SYSCALL_ENTRY was reported.
Will continue tomorrow.
---
kernel/ptrace.c | 19 ++++++++++++-------
1 file changed, 12 insertions(+), 7 deletions(-)
--- PU/kernel/ptrace.c~104_PTRACE_SYSEMU 2009-10-18 19:56:28.000000000
+0200
+++ PU/kernel/ptrace.c 2009-10-19 18:46:50.000000000 +0200
@@ -25,7 +25,9 @@
#include <linux/uaccess.h>
struct ptrace_context {
- int options;
+ int options;
+
+ bool sysemu; // XXX: will die soon
int signr;
siginfo_t *siginfo;
@@ -250,6 +252,8 @@ static u32 ptrace_report_syscall_entry(u
set_syscall_code(context, PTRACE_EVENT_SYSCALL_ENTRY);
+ if (unlikely(context->sysemu))
+ return UTRACE_SYSCALL_ABORT | UTRACE_STOP;
return UTRACE_SYSCALL_RUN | UTRACE_STOP;
}
@@ -1012,16 +1016,16 @@ static void do_ptrace_resume(struct utra
static int ptrace_resume(struct utrace_engine *engine,
struct task_struct *tracee, long request, long data)
{
+ struct ptrace_context *context = ptrace_context(engine);
enum utrace_resume_action action;
- enum utrace_syscall_action syscall;
unsigned long events;
if (!valid_signal(data))
return -EIO;
- syscall = UTRACE_SYSCALL_RUN;
- events = engine->flags & ~UTRACE_EVENT_SYSCALL;
- action = UTRACE_RESUME;
+ context->sysemu = false;
+ events = engine->flags & ~UTRACE_EVENT_SYSCALL;
+ action = UTRACE_RESUME;
switch (request) {
#ifdef PTRACE_SINGLEBLOCK
@@ -1046,8 +1050,9 @@ static int ptrace_resume(struct utrace_e
return -EIO;
action = UTRACE_SINGLESTEP;
case PTRACE_SYSEMU:
- syscall = UTRACE_SYSCALL_ABORT;
- /* fallthrough */
+ context->sysemu = true;
+ events |= UTRACE_EVENT(SYSCALL_ENTRY);
+ break;
#endif
case PTRACE_SYSCALL:
