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Diffstat (limited to 'kernel/ptrace.c')
-rw-r--r--kernel/ptrace.c173
1 files changed, 170 insertions, 3 deletions
diff --git a/kernel/ptrace.c b/kernel/ptrace.c
index 26f9923baddc..b0d4ab4dfd3d 100644
--- a/kernel/ptrace.c
+++ b/kernel/ptrace.c
@@ -120,7 +120,7 @@ int ptrace_check_attach(struct task_struct *child, int kill)
return ret;
}
-static int may_attach(struct task_struct *task)
+int __ptrace_may_attach(struct task_struct *task)
{
/* May we inspect the given task?
* This check is used both for attaching with ptrace
@@ -154,7 +154,7 @@ int ptrace_may_attach(struct task_struct *task)
{
int err;
task_lock(task);
- err = may_attach(task);
+ err = __ptrace_may_attach(task);
task_unlock(task);
return !err;
}
@@ -196,7 +196,7 @@ repeat:
/* the same process cannot be attached many times */
if (task->ptrace & PT_PTRACED)
goto bad;
- retval = may_attach(task);
+ retval = __ptrace_may_attach(task);
if (retval)
goto bad;
@@ -366,12 +366,73 @@ static int ptrace_setsiginfo(struct task_struct *child, siginfo_t __user * data)
return error;
}
+
+#ifdef PTRACE_SINGLESTEP
+#define is_singlestep(request) ((request) == PTRACE_SINGLESTEP)
+#else
+#define is_singlestep(request) 0
+#endif
+
+#ifdef PTRACE_SINGLEBLOCK
+#define is_singleblock(request) ((request) == PTRACE_SINGLEBLOCK)
+#else
+#define is_singleblock(request) 0
+#endif
+
+#ifdef PTRACE_SYSEMU
+#define is_sysemu_singlestep(request) ((request) == PTRACE_SYSEMU_SINGLESTEP)
+#else
+#define is_sysemu_singlestep(request) 0
+#endif
+
+static int ptrace_resume(struct task_struct *child, long request, long data)
+{
+ if (!valid_signal(data))
+ return -EIO;
+
+ if (request == PTRACE_SYSCALL)
+ set_tsk_thread_flag(child, TIF_SYSCALL_TRACE);
+ else
+ clear_tsk_thread_flag(child, TIF_SYSCALL_TRACE);
+
+#ifdef TIF_SYSCALL_EMU
+ if (request == PTRACE_SYSEMU || request == PTRACE_SYSEMU_SINGLESTEP)
+ set_tsk_thread_flag(child, TIF_SYSCALL_EMU);
+ else
+ clear_tsk_thread_flag(child, TIF_SYSCALL_EMU);
+#endif
+
+ if (is_singleblock(request)) {
+ if (unlikely(!arch_has_block_step()))
+ return -EIO;
+ user_enable_block_step(child);
+ } else if (is_singlestep(request) || is_sysemu_singlestep(request)) {
+ if (unlikely(!arch_has_single_step()))
+ return -EIO;
+ user_enable_single_step(child);
+ }
+ else
+ user_disable_single_step(child);
+
+ child->exit_code = data;
+ wake_up_process(child);
+
+ return 0;
+}
+
int ptrace_request(struct task_struct *child, long request,
long addr, long data)
{
int ret = -EIO;
switch (request) {
+ case PTRACE_PEEKTEXT:
+ case PTRACE_PEEKDATA:
+ return generic_ptrace_peekdata(child, addr, data);
+ case PTRACE_POKETEXT:
+ case PTRACE_POKEDATA:
+ return generic_ptrace_pokedata(child, addr, data);
+
#ifdef PTRACE_OLDSETOPTIONS
case PTRACE_OLDSETOPTIONS:
#endif
@@ -390,6 +451,26 @@ int ptrace_request(struct task_struct *child, long request,
case PTRACE_DETACH: /* detach a process that was attached. */
ret = ptrace_detach(child, data);
break;
+
+#ifdef PTRACE_SINGLESTEP
+ case PTRACE_SINGLESTEP:
+#endif
+#ifdef PTRACE_SINGLEBLOCK
+ case PTRACE_SINGLEBLOCK:
+#endif
+#ifdef PTRACE_SYSEMU
+ case PTRACE_SYSEMU:
+ case PTRACE_SYSEMU_SINGLESTEP:
+#endif
+ case PTRACE_SYSCALL:
+ case PTRACE_CONT:
+ return ptrace_resume(child, request, data);
+
+ case PTRACE_KILL:
+ if (child->exit_state) /* already dead */
+ return 0;
+ return ptrace_resume(child, request, SIGKILL);
+
default:
break;
}
@@ -470,6 +551,8 @@ asmlinkage long sys_ptrace(long request, long pid, long addr, long data)
lock_kernel();
if (request == PTRACE_TRACEME) {
ret = ptrace_traceme();
+ if (!ret)
+ arch_ptrace_attach(current);
goto out;
}
@@ -524,3 +607,87 @@ int generic_ptrace_pokedata(struct task_struct *tsk, long addr, long data)
copied = access_process_vm(tsk, addr, &data, sizeof(data), 1);
return (copied == sizeof(data)) ? 0 : -EIO;
}
+
+#ifdef CONFIG_COMPAT
+#include <linux/compat.h>
+
+int compat_ptrace_request(struct task_struct *child, compat_long_t request,
+ compat_ulong_t addr, compat_ulong_t data)
+{
+ compat_ulong_t __user *datap = compat_ptr(data);
+ compat_ulong_t word;
+ int ret;
+
+ switch (request) {
+ case PTRACE_PEEKTEXT:
+ case PTRACE_PEEKDATA:
+ ret = access_process_vm(child, addr, &word, sizeof(word), 0);
+ if (ret != sizeof(word))
+ ret = -EIO;
+ else
+ ret = put_user(word, datap);
+ break;
+
+ case PTRACE_POKETEXT:
+ case PTRACE_POKEDATA:
+ ret = access_process_vm(child, addr, &data, sizeof(data), 1);
+ ret = (ret != sizeof(data) ? -EIO : 0);
+ break;
+
+ case PTRACE_GETEVENTMSG:
+ ret = put_user((compat_ulong_t) child->ptrace_message, datap);
+ break;
+
+ default:
+ ret = ptrace_request(child, request, addr, data);
+ }
+
+ return ret;
+}
+
+#ifdef __ARCH_WANT_COMPAT_SYS_PTRACE
+asmlinkage long compat_sys_ptrace(compat_long_t request, compat_long_t pid,
+ compat_long_t addr, compat_long_t data)
+{
+ struct task_struct *child;
+ long ret;
+
+ /*
+ * This lock_kernel fixes a subtle race with suid exec
+ */
+ lock_kernel();
+ if (request == PTRACE_TRACEME) {
+ ret = ptrace_traceme();
+ goto out;
+ }
+
+ child = ptrace_get_task_struct(pid);
+ if (IS_ERR(child)) {
+ ret = PTR_ERR(child);
+ goto out;
+ }
+
+ if (request == PTRACE_ATTACH) {
+ ret = ptrace_attach(child);
+ /*
+ * Some architectures need to do book-keeping after
+ * a ptrace attach.
+ */
+ if (!ret)
+ arch_ptrace_attach(child);
+ goto out_put_task_struct;
+ }
+
+ ret = ptrace_check_attach(child, request == PTRACE_KILL);
+ if (!ret)
+ ret = compat_arch_ptrace(child, request, addr, data);
+
+ out_put_task_struct:
+ put_task_struct(child);
+ out:
+ unlock_kernel();
+ return ret;
+}
+#endif /* __ARCH_WANT_COMPAT_SYS_PTRACE */
+
+#endif /* CONFIG_COMPAT */