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authorDave Jones <davej@redhat.com>2011-05-09 16:41:28 -0400
committerDave Jones <davej@redhat.com>2011-05-09 16:41:28 -0400
commit57671e4ed5e8ec1546c5b38222cee66d5ea32dee (patch)
tree6ca2b46de7b5d4092ea70f23b28a354c7720b4a6 /linux-2.6-utrace-ptrace.patch
parent9de65275ff9c115edcf583ed209f5d5c50fbbf1d (diff)
downloadkernel-57671e4ed5e8ec1546c5b38222cee66d5ea32dee.tar.gz
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adios utrace.
Diffstat (limited to 'linux-2.6-utrace-ptrace.patch')
-rw-r--r--linux-2.6-utrace-ptrace.patch2027
1 files changed, 0 insertions, 2027 deletions
diff --git a/linux-2.6-utrace-ptrace.patch b/linux-2.6-utrace-ptrace.patch
deleted file mode 100644
index 9d6e729a7..000000000
--- a/linux-2.6-utrace-ptrace.patch
+++ /dev/null
@@ -1,2027 +0,0 @@
-implement utrace-ptrace
-
-The patch adds the new file, kernel/ptrace-utrace.c, which contains
-the new implementation of ptrace over utrace.
-
-This file is not compiled until we have CONFIG_UTRACE option, will be
-added by the next "utrace core" patch.
-
-It's supposed to be an invisible implementation change, nothing should
-change to userland when CONFIG_UTRACE is enabled.
-
-Signed-off-by: Roland McGrath <roland@redhat.com>
-Signed-off-by: Oleg Nesterov <oleg@redhat.com>
----
- include/linux/ptrace.h | 1 +
- kernel/Makefile | 1 +
- kernel/ptrace-utrace.c | 1187 ++++++++++++++++++++++++++++++++++++++++++++++++
- kernel/ptrace.c | 690 ++++++++++++++--------------
- kernel/utrace.c | 16 +
- 5 files changed, 1544 insertions(+), 351 deletions(-)
-
-diff --git a/include/linux/ptrace.h b/include/linux/ptrace.h
-index 619cdf0..e391bdb 100644
---- a/include/linux/ptrace.h
-+++ b/include/linux/ptrace.h
-@@ -100,6 +100,7 @@
- #include <linux/sched.h> /* For struct task_struct. */
-
-
-+extern void ptrace_notify_stop(struct task_struct *tracee);
- extern long arch_ptrace(struct task_struct *child, long request,
- unsigned long addr, unsigned long data);
- extern int ptrace_traceme(void);
-diff --git a/kernel/Makefile b/kernel/Makefile
-index 1172528..9a815a5 100644
---- a/kernel/Makefile
-+++ b/kernel/Makefile
-@@ -71,6 +71,7 @@ obj-$(CONFIG_RESOURCE_COUNTERS) += res_c
- obj-$(CONFIG_SMP) += stop_machine.o
- obj-$(CONFIG_KPROBES_SANITY_TEST) += test_kprobes.o
- obj-$(CONFIG_UTRACE) += utrace.o
-+obj-$(CONFIG_UTRACE) += ptrace-utrace.o
- obj-$(CONFIG_AUDIT) += audit.o auditfilter.o
- obj-$(CONFIG_AUDITSYSCALL) += auditsc.o
- obj-$(CONFIG_AUDIT_WATCH) += audit_watch.o
-diff --git a/kernel/ptrace-utrace.c b/kernel/ptrace-utrace.c
-new file mode 100644
-index ...a5bcb9e 100644
---- /dev/null
-+++ b/kernel/ptrace-utrace.c
-@@ -0,0 +1,1186 @@
-+/*
-+ * linux/kernel/ptrace.c
-+ *
-+ * (C) Copyright 1999 Linus Torvalds
-+ *
-+ * Common interfaces for "ptrace()" which we do not want
-+ * to continually duplicate across every architecture.
-+ */
-+
-+#include <linux/capability.h>
-+#include <linux/module.h>
-+#include <linux/sched.h>
-+#include <linux/errno.h>
-+#include <linux/mm.h>
-+#include <linux/highmem.h>
-+#include <linux/pagemap.h>
-+#include <linux/ptrace.h>
-+#include <linux/utrace.h>
-+#include <linux/security.h>
-+#include <linux/signal.h>
-+#include <linux/audit.h>
-+#include <linux/pid_namespace.h>
-+#include <linux/syscalls.h>
-+#include <linux/uaccess.h>
-+
-+/*
-+ * ptrace a task: make the debugger its new parent and
-+ * move it to the ptrace list.
-+ *
-+ * Must be called with the tasklist lock write-held.
-+ */
-+void __ptrace_link(struct task_struct *child, struct task_struct *new_parent)
-+{
-+ BUG_ON(!list_empty(&child->ptrace_entry));
-+ list_add(&child->ptrace_entry, &new_parent->ptraced);
-+ child->parent = new_parent;
-+}
-+
-+/*
-+ * unptrace a task: move it back to its original parent and
-+ * remove it from the ptrace list.
-+ *
-+ * Must be called with the tasklist lock write-held.
-+ */
-+void __ptrace_unlink(struct task_struct *child)
-+{
-+ BUG_ON(!child->ptrace);
-+
-+ child->ptrace = 0;
-+ child->parent = child->real_parent;
-+ list_del_init(&child->ptrace_entry);
-+}
-+
-+struct ptrace_context {
-+ int options;
-+
-+ int signr;
-+ siginfo_t *siginfo;
-+
-+ int stop_code;
-+ unsigned long eventmsg;
-+
-+ enum utrace_resume_action resume;
-+};
-+
-+#define PT_UTRACED 0x00001000
-+
-+#define PTRACE_O_SYSEMU 0x100
-+#define PTRACE_O_DETACHED 0x200
-+
-+#define PTRACE_EVENT_SYSCALL (1 << 16)
-+#define PTRACE_EVENT_SIGTRAP (2 << 16)
-+#define PTRACE_EVENT_SIGNAL (3 << 16)
-+/* events visible to user-space */
-+#define PTRACE_EVENT_MASK 0xFFFF
-+
-+static inline bool ptrace_event_pending(struct ptrace_context *ctx)
-+{
-+ return ctx->stop_code != 0;
-+}
-+
-+static inline int get_stop_event(struct ptrace_context *ctx)
-+{
-+ return ctx->stop_code >> 8;
-+}
-+
-+static inline void set_stop_code(struct ptrace_context *ctx, int event)
-+{
-+ ctx->stop_code = (event << 8) | SIGTRAP;
-+}
-+
-+static inline struct ptrace_context *
-+ptrace_context(struct utrace_engine *engine)
-+{
-+ return engine->data;
-+}
-+
-+static const struct utrace_engine_ops ptrace_utrace_ops; /* forward decl */
-+
-+static struct utrace_engine *ptrace_lookup_engine(struct task_struct *tracee)
-+{
-+ return utrace_attach_task(tracee, UTRACE_ATTACH_MATCH_OPS,
-+ &ptrace_utrace_ops, NULL);
-+}
-+
-+static int utrace_barrier_uninterruptible(struct task_struct *target,
-+ struct utrace_engine *engine)
-+{
-+ for (;;) {
-+ int err = utrace_barrier(target, engine);
-+
-+ if (err != -ERESTARTSYS)
-+ return err;
-+
-+ schedule_timeout_uninterruptible(1);
-+ }
-+}
-+
-+static struct utrace_engine *
-+ptrace_reuse_engine(struct task_struct *tracee)
-+{
-+ struct utrace_engine *engine;
-+ struct ptrace_context *ctx;
-+ int err = -EPERM;
-+
-+ engine = ptrace_lookup_engine(tracee);
-+ if (IS_ERR(engine))
-+ return engine;
-+
-+ ctx = ptrace_context(engine);
-+ if (unlikely(ctx->options == PTRACE_O_DETACHED)) {
-+ /*
-+ * Try to reuse this self-detaching engine.
-+ * The only caller which can hit this case is ptrace_attach(),
-+ * it holds ->cred_guard_mutex.
-+ */
-+ ctx->options = 0;
-+ ctx->eventmsg = 0;
-+
-+ /* make sure we don't get unwanted reports */
-+ err = utrace_set_events(tracee, engine, UTRACE_EVENT(QUIESCE));
-+ if (!err || err == -EINPROGRESS) {
-+ ctx->resume = UTRACE_RESUME;
-+ /* synchronize with ptrace_report_signal() */
-+ err = utrace_barrier_uninterruptible(tracee, engine);
-+ }
-+
-+ if (!err) {
-+ WARN_ON(engine->ops != &ptrace_utrace_ops &&
-+ !tracee->exit_state);
-+ return engine;
-+ }
-+
-+ WARN_ON(engine->ops == &ptrace_utrace_ops);
-+ }
-+
-+ utrace_engine_put(engine);
-+ return ERR_PTR(err);
-+}
-+
-+static struct utrace_engine *
-+ptrace_attach_engine(struct task_struct *tracee)
-+{
-+ struct utrace_engine *engine;
-+ struct ptrace_context *ctx;
-+
-+ if (unlikely(task_utrace_flags(tracee))) {
-+ engine = ptrace_reuse_engine(tracee);
-+ if (!IS_ERR(engine) || IS_ERR(engine) == -EPERM)
-+ return engine;
-+ }
-+
-+ ctx = kzalloc(sizeof(*ctx), GFP_KERNEL);
-+ if (unlikely(!ctx))
-+ return ERR_PTR(-ENOMEM);
-+
-+ ctx->resume = UTRACE_RESUME;
-+
-+ engine = utrace_attach_task(tracee, UTRACE_ATTACH_CREATE |
-+ UTRACE_ATTACH_EXCLUSIVE |
-+ UTRACE_ATTACH_MATCH_OPS,
-+ &ptrace_utrace_ops, ctx);
-+ if (unlikely(IS_ERR(engine))) {
-+ if (engine != ERR_PTR(-ESRCH) &&
-+ engine != ERR_PTR(-ERESTARTNOINTR))
-+ engine = ERR_PTR(-EPERM);
-+ kfree(ctx);
-+ }
-+
-+ return engine;
-+}
-+
-+static inline int ptrace_set_events(struct task_struct *target,
-+ struct utrace_engine *engine,
-+ unsigned long options)
-+{
-+ struct ptrace_context *ctx = ptrace_context(engine);
-+ /*
-+ * We need QUIESCE for resume handling, CLONE to check
-+ * for CLONE_PTRACE, other events are always reported.
-+ */
-+ unsigned long events = UTRACE_EVENT(QUIESCE) | UTRACE_EVENT(CLONE) |
-+ UTRACE_EVENT(EXEC) | UTRACE_EVENT_SIGNAL_ALL;
-+
-+ ctx->options = options;
-+ if (options & PTRACE_O_TRACEEXIT)
-+ events |= UTRACE_EVENT(EXIT);
-+
-+ return utrace_set_events(target, engine, events);
-+}
-+
-+/*
-+ * Attach a utrace engine for ptrace and set up its event mask.
-+ * Returns error code or 0 on success.
-+ */
-+static int ptrace_attach_task(struct task_struct *tracee, int options)
-+{
-+ struct utrace_engine *engine;
-+ int err;
-+
-+ engine = ptrace_attach_engine(tracee);
-+ if (IS_ERR(engine))
-+ return PTR_ERR(engine);
-+ /*
-+ * It can fail only if the tracee is dead, the caller
-+ * must notice this before setting PT_UTRACED.
-+ */
-+ err = ptrace_set_events(tracee, engine, options);
-+ WARN_ON(err && !tracee->exit_state);
-+ utrace_engine_put(engine);
-+ return 0;
-+}
-+
-+static int ptrace_wake_up(struct task_struct *tracee,
-+ struct utrace_engine *engine,
-+ enum utrace_resume_action action,
-+ bool force_wakeup)
-+{
-+ if (force_wakeup) {
-+ unsigned long flags;
-+ /*
-+ * Preserve the compatibility bug. Historically ptrace
-+ * wakes up the tracee even if it should not. Clear
-+ * SIGNAL_STOP_STOPPED for utrace_wakeup().
-+ */
-+ if (lock_task_sighand(tracee, &flags)) {
-+ tracee->signal->flags &= ~SIGNAL_STOP_STOPPED;
-+ unlock_task_sighand(tracee, &flags);
-+ }
-+ }
-+
-+ if (action != UTRACE_REPORT)
-+ ptrace_context(engine)->stop_code = 0;
-+
-+ return utrace_control(tracee, engine, action);
-+}
-+
-+static void ptrace_detach_task(struct task_struct *tracee, int sig)
-+{
-+ /*
-+ * If true, the caller is PTRACE_DETACH, otherwise
-+ * the tracer detaches implicitly during exit.
-+ */
-+ bool explicit = (sig >= 0);
-+ struct utrace_engine *engine = ptrace_lookup_engine(tracee);
-+ enum utrace_resume_action action = UTRACE_DETACH;
-+ struct ptrace_context *ctx;
-+
-+ if (unlikely(IS_ERR(engine)))
-+ return;
-+
-+ ctx = ptrace_context(engine);
-+
-+ if (!explicit) {
-+ int err;
-+
-+ /*
-+ * We are going to detach, the tracee can be running.
-+ * Ensure ptrace_report_signal() won't report a signal.
-+ */
-+ ctx->resume = UTRACE_DETACH;
-+ err = utrace_barrier_uninterruptible(tracee, engine);
-+
-+ if (!err && ctx->siginfo) {
-+ /*
-+ * The tracee has already reported a signal
-+ * before utrace_barrier().
-+ *
-+ * Resume it like we do in PTRACE_EVENT_SIGNAL
-+ * case below. The difference is that we can race
-+ * with ptrace_report_signal() if the tracee is
-+ * running but this doesn't matter. In any case
-+ * UTRACE_SIGNAL_REPORT must be pending and it
-+ * can return nothing but UTRACE_DETACH.
-+ */
-+ action = UTRACE_RESUME;
-+ }
-+
-+ } else if (sig) {
-+ switch (get_stop_event(ctx)) {
-+ case PTRACE_EVENT_SYSCALL:
-+ send_sig_info(sig, SEND_SIG_PRIV, tracee);
-+ break;
-+
-+ case PTRACE_EVENT_SIGNAL:
-+ ctx->signr = sig;
-+ ctx->resume = UTRACE_DETACH;
-+ action = UTRACE_RESUME;
-+ break;
-+ }
-+ }
-+
-+ ptrace_wake_up(tracee, engine, action, explicit);
-+
-+ if (action != UTRACE_DETACH)
-+ ctx->options = PTRACE_O_DETACHED;
-+
-+ utrace_engine_put(engine);
-+}
-+
-+static void ptrace_abort_attach(struct task_struct *tracee)
-+{
-+ ptrace_detach_task(tracee, 0);
-+}
-+
-+static u32 ptrace_report_exit(u32 action, struct utrace_engine *engine,
-+ long orig_code, long *code)
-+{
-+ struct ptrace_context *ctx = ptrace_context(engine);
-+
-+ WARN_ON(ptrace_event_pending(ctx) &&
-+ !signal_group_exit(current->signal));
-+
-+ set_stop_code(ctx, PTRACE_EVENT_EXIT);
-+ ctx->eventmsg = *code;
-+
-+ return UTRACE_STOP;
-+}
-+
-+static void ptrace_clone_attach(struct task_struct *child,
-+ int options)
-+{
-+ struct task_struct *parent = current;
-+ struct task_struct *tracer;
-+ bool abort = true;
-+
-+ if (unlikely(ptrace_attach_task(child, options))) {
-+ WARN_ON(1);
-+ return;
-+ }
-+
-+ write_lock_irq(&tasklist_lock);
-+ tracer = parent->parent;
-+ if (!(tracer->flags & PF_EXITING) && parent->ptrace) {
-+ child->ptrace = parent->ptrace;
-+ __ptrace_link(child, tracer);
-+ abort = false;
-+ }
-+ write_unlock_irq(&tasklist_lock);
-+ if (unlikely(abort)) {
-+ ptrace_abort_attach(child);
-+ return;
-+ }
-+
-+ sigaddset(&child->pending.signal, SIGSTOP);
-+ set_tsk_thread_flag(child, TIF_SIGPENDING);
-+}
-+
-+static u32 ptrace_report_clone(u32 action, struct utrace_engine *engine,
-+ unsigned long clone_flags,
-+ struct task_struct *child)
-+{
-+ struct ptrace_context *ctx = ptrace_context(engine);
-+ int event = 0;
-+
-+ WARN_ON(ptrace_event_pending(ctx));
-+
-+ if (clone_flags & CLONE_UNTRACED) {
-+ /* no events reported */
-+ } else if (clone_flags & CLONE_VFORK) {
-+ if (ctx->options & PTRACE_O_TRACEVFORK)
-+ event = PTRACE_EVENT_VFORK;
-+ else if (ctx->options & PTRACE_O_TRACEVFORKDONE)
-+ event = PTRACE_EVENT_VFORK_DONE;
-+ } else if ((clone_flags & CSIGNAL) != SIGCHLD) {
-+ if (ctx->options & PTRACE_O_TRACECLONE)
-+ event = PTRACE_EVENT_CLONE;
-+ } else if (ctx->options & PTRACE_O_TRACEFORK) {
-+ event = PTRACE_EVENT_FORK;
-+ }
-+ /*
-+ * Any of these reports implies auto-attaching the new child.
-+ * So does CLONE_PTRACE, even with no event to report.
-+ */
-+ if ((event && event != PTRACE_EVENT_VFORK_DONE) ||
-+ (clone_flags & CLONE_PTRACE))
-+ ptrace_clone_attach(child, ctx->options);
-+
-+ if (!event)
-+ return UTRACE_RESUME;
-+
-+ set_stop_code(ctx, event);
-+ ctx->eventmsg = child->pid;
-+ /*
-+ * We shouldn't stop now, inside the do_fork() path.
-+ * We will stop later, before return to user-mode.
-+ */
-+ if (event == PTRACE_EVENT_VFORK_DONE)
-+ return UTRACE_REPORT;
-+ else
-+ return UTRACE_STOP;
-+}
-+
-+static inline void set_syscall_code(struct ptrace_context *ctx)
-+{
-+ set_stop_code(ctx, PTRACE_EVENT_SYSCALL);
-+ if (ctx->options & PTRACE_O_TRACESYSGOOD)
-+ ctx->stop_code |= 0x80;
-+}
-+
-+static u32 ptrace_report_syscall_entry(u32 action, struct utrace_engine *engine,
-+ struct pt_regs *regs)
-+{
-+ struct ptrace_context *ctx = ptrace_context(engine);
-+
-+ if (action & UTRACE_SYSCALL_RESUMED) {
-+ /*
-+ * We already reported the first time.
-+ * Nothing more to do now.
-+ */
-+ if (unlikely(ctx->options & PTRACE_O_SYSEMU))
-+ return UTRACE_SYSCALL_ABORT | UTRACE_REPORT;
-+ return utrace_syscall_action(action) | UTRACE_RESUME;
-+ }
-+
-+ WARN_ON(ptrace_event_pending(ctx));
-+
-+ set_syscall_code(ctx);
-+
-+ if (unlikely(ctx->options & PTRACE_O_SYSEMU))
-+ return UTRACE_SYSCALL_ABORT | UTRACE_REPORT;
-+ /*
-+ * Stop now to report. We will get another callback after
-+ * we resume, with the UTRACE_SYSCALL_RESUMED flag set.
-+ */
-+ return UTRACE_SYSCALL_RUN | UTRACE_STOP;
-+}
-+
-+static inline bool is_step_resume(enum utrace_resume_action resume)
-+{
-+ return resume == UTRACE_BLOCKSTEP || resume == UTRACE_SINGLESTEP;
-+}
-+
-+static u32 ptrace_report_syscall_exit(u32 action, struct utrace_engine *engine,
-+ struct pt_regs *regs)
-+{
-+ struct ptrace_context *ctx = ptrace_context(engine);
-+
-+ if (ptrace_event_pending(ctx))
-+ return UTRACE_STOP;
-+
-+ if (is_step_resume(ctx->resume)) {
-+ ctx->signr = SIGTRAP;
-+ return UTRACE_INTERRUPT;
-+ }
-+
-+ set_syscall_code(ctx);
-+ return UTRACE_STOP;
-+}
-+
-+static u32 ptrace_report_exec(u32 action, struct utrace_engine *engine,
-+ const struct linux_binfmt *fmt,
-+ const struct linux_binprm *bprm,
-+ struct pt_regs *regs)
-+{
-+ struct ptrace_context *ctx = ptrace_context(engine);
-+
-+ WARN_ON(ptrace_event_pending(ctx));
-+
-+ if (!(ctx->options & PTRACE_O_TRACEEXEC)) {
-+ /*
-+ * Old-fashioned ptrace'd exec just posts a plain signal.
-+ */
-+ send_sig(SIGTRAP, current, 0);
-+ return UTRACE_RESUME;
-+ }
-+
-+ set_stop_code(ctx, PTRACE_EVENT_EXEC);
-+ return UTRACE_STOP;
-+}
-+
-+static enum utrace_signal_action resume_signal(struct ptrace_context *ctx,
-+ struct k_sigaction *return_ka)
-+{
-+ siginfo_t *info = ctx->siginfo;
-+ int signr = ctx->signr;
-+
-+ ctx->siginfo = NULL;
-+ ctx->signr = 0;
-+
-+ /* Did the debugger cancel the sig? */
-+ if (!signr)
-+ return UTRACE_SIGNAL_IGN;
-+ /*
-+ * Update the siginfo structure if the signal has changed.
-+ * If the debugger wanted something specific in the siginfo
-+ * then it should have updated *info via PTRACE_SETSIGINFO.
-+ */
-+ if (info->si_signo != signr) {
-+ info->si_signo = signr;
-+ info->si_errno = 0;
-+ info->si_code = SI_USER;
-+ info->si_pid = task_pid_vnr(current->parent);
-+ info->si_uid = task_uid(current->parent);
-+ }
-+
-+ /* If the (new) signal is now blocked, requeue it. */
-+ if (sigismember(&current->blocked, signr)) {
-+ send_sig_info(signr, info, current);
-+ return UTRACE_SIGNAL_IGN;
-+ }
-+
-+ spin_lock_irq(&current->sighand->siglock);
-+ *return_ka = current->sighand->action[signr - 1];
-+ spin_unlock_irq(&current->sighand->siglock);
-+
-+ return UTRACE_SIGNAL_DELIVER;
-+}
-+
-+static u32 ptrace_report_signal(u32 action, struct utrace_engine *engine,
-+ struct pt_regs *regs,
-+ siginfo_t *info,
-+ const struct k_sigaction *orig_ka,
-+ struct k_sigaction *return_ka)
-+{
-+ struct ptrace_context *ctx = ptrace_context(engine);
-+ enum utrace_resume_action resume = ctx->resume;
-+
-+ if (ptrace_event_pending(ctx)) {
-+ action = utrace_signal_action(action);
-+ WARN_ON(action != UTRACE_SIGNAL_REPORT);
-+ return action | UTRACE_STOP;
-+ }
-+
-+ switch (utrace_signal_action(action)) {
-+ case UTRACE_SIGNAL_HANDLER:
-+ if (WARN_ON(ctx->siginfo))
-+ ctx->siginfo = NULL;
-+
-+ if (is_step_resume(resume)) {
-+ set_stop_code(ctx, PTRACE_EVENT_SIGTRAP);
-+ return UTRACE_STOP | UTRACE_SIGNAL_IGN;
-+ }
-+
-+ case UTRACE_SIGNAL_REPORT:
-+ if (!ctx->siginfo) {
-+ if (ctx->signr) {
-+ /* set by ptrace_resume(SYSCALL_EXIT) */
-+ WARN_ON(ctx->signr != SIGTRAP);
-+ user_single_step_siginfo(current, regs, info);
-+ force_sig_info(SIGTRAP, info, current);
-+ }
-+
-+ return resume | UTRACE_SIGNAL_IGN;
-+ }
-+
-+ if (WARN_ON(ctx->siginfo != info))
-+ return resume | UTRACE_SIGNAL_IGN;
-+
-+ return resume | resume_signal(ctx, return_ka);
-+
-+ default:
-+ break;
-+ }
-+
-+ WARN_ON(ctx->siginfo);
-+
-+ /* Raced with the exiting tracer ? */
-+ if (resume == UTRACE_DETACH)
-+ return action;
-+
-+ ctx->siginfo = info;
-+ /*
-+ * ctx->siginfo points to the caller's stack.
-+ * Make sure the subsequent UTRACE_SIGNAL_REPORT clears
-+ * ->siginfo before return from get_signal_to_deliver().
-+ */
-+ if (utrace_control(current, engine, UTRACE_INTERRUPT))
-+ WARN_ON(1);
-+
-+ ctx->signr = info->si_signo;
-+ ctx->stop_code = (PTRACE_EVENT_SIGNAL << 8) | ctx->signr;
-+
-+ return UTRACE_STOP | UTRACE_SIGNAL_IGN;
-+}
-+
-+static u32 ptrace_report_quiesce(u32 action, struct utrace_engine *engine,
-+ unsigned long event)
-+{
-+ struct ptrace_context *ctx = ptrace_context(engine);
-+
-+ if (ptrace_event_pending(ctx))
-+ return UTRACE_STOP;
-+
-+ return event ? UTRACE_RESUME : ctx->resume;
-+}
-+
-+static void ptrace_release(void *data)
-+{
-+ kfree(data);
-+}
-+
-+static const struct utrace_engine_ops ptrace_utrace_ops = {
-+ .report_signal = ptrace_report_signal,
-+ .report_quiesce = ptrace_report_quiesce,
-+ .report_exec = ptrace_report_exec,
-+ .report_exit = ptrace_report_exit,
-+ .report_clone = ptrace_report_clone,
-+ .report_syscall_entry = ptrace_report_syscall_entry,
-+ .report_syscall_exit = ptrace_report_syscall_exit,
-+ .release = ptrace_release,
-+};
-+
-+int ptrace_check_attach(struct task_struct *child, int kill)
-+{
-+ struct utrace_engine *engine;
-+ struct utrace_examiner exam;
-+ int ret = -ESRCH;
-+
-+ engine = ptrace_lookup_engine(child);
-+ if (IS_ERR(engine))
-+ return ret;
-+
-+ if (child->parent != current)
-+ goto out;
-+
-+ if (unlikely(kill))
-+ ret = 0;
-+
-+ if (!task_is_stopped_or_traced(child))
-+ goto out;
-+ /*
-+ * Make sure our engine has already stopped the child.
-+ * Then wait for it to be off the CPU.
-+ */
-+ if (!utrace_control(child, engine, UTRACE_STOP) &&
-+ !utrace_prepare_examine(child, engine, &exam))
-+ ret = 0;
-+out:
-+ utrace_engine_put(engine);
-+ return ret;
-+}
-+
-+int ptrace_attach(struct task_struct *task)
-+{
-+ int retval;
-+
-+ audit_ptrace(task);
-+
-+ retval = -EPERM;
-+ if (unlikely(task->flags & PF_KTHREAD))
-+ goto out;
-+ if (same_thread_group(task, current))
-+ goto out;
-+
-+ /*
-+ * Protect exec's credential calculations against our interference;
-+ * interference; SUID, SGID and LSM creds get determined differently
-+ * under ptrace.
-+ */
-+ retval = -ERESTARTNOINTR;
-+ if (mutex_lock_interruptible(&task->signal->cred_guard_mutex))
-+ goto out;
-+
-+ task_lock(task);
-+ retval = __ptrace_may_access(task, PTRACE_MODE_ATTACH);
-+ task_unlock(task);
-+ if (retval)
-+ goto unlock_creds;
-+
-+ retval = ptrace_attach_task(task, 0);
-+ if (unlikely(retval))
-+ goto unlock_creds;
-+
-+ write_lock_irq(&tasklist_lock);
-+ retval = -EPERM;
-+ if (unlikely(task->exit_state))
-+ goto unlock_tasklist;
-+
-+ BUG_ON(task->ptrace);
-+ task->ptrace = PT_UTRACED;
-+ if (capable(CAP_SYS_PTRACE))
-+ task->ptrace |= PT_PTRACE_CAP;
-+
-+ __ptrace_link(task, current);
-+ send_sig_info(SIGSTOP, SEND_SIG_FORCED, task);
-+
-+ retval = 0;
-+unlock_tasklist:
-+ write_unlock_irq(&tasklist_lock);
-+unlock_creds:
-+ mutex_unlock(&task->signal->cred_guard_mutex);
-+out:
-+ return retval;
-+}
-+
-+/*
-+ * Performs checks and sets PT_UTRACED.
-+ * Should be used by all ptrace implementations for PTRACE_TRACEME.
-+ */
-+int ptrace_traceme(void)
-+{
-+ bool detach = true;
-+ int ret = ptrace_attach_task(current, 0);
-+
-+ if (unlikely(ret))
-+ return ret;
-+
-+ ret = -EPERM;
-+ write_lock_irq(&tasklist_lock);
-+ BUG_ON(current->ptrace);
-+ ret = security_ptrace_traceme(current->parent);
-+ /*
-+ * Check PF_EXITING to ensure ->real_parent has not passed
-+ * exit_ptrace(). Otherwise we don't report the error but
-+ * pretend ->real_parent untraces us right after return.
-+ */
-+ if (!ret && !(current->real_parent->flags & PF_EXITING)) {
-+ current->ptrace = PT_UTRACED;
-+ __ptrace_link(current, current->real_parent);
-+ detach = false;
-+ }
-+ write_unlock_irq(&tasklist_lock);
-+
-+ if (detach)
-+ ptrace_abort_attach(current);
-+ return ret;
-+}
-+
-+static void ptrace_do_detach(struct task_struct *tracee, unsigned int data)
-+{
-+ bool detach, release;
-+
-+ write_lock_irq(&tasklist_lock);
-+ /*
-+ * This tracee can be already killed. Make sure de_thread() or
-+ * our sub-thread doing do_wait() didn't do release_task() yet.
-+ */
-+ detach = tracee->ptrace != 0;
-+ release = false;
-+ if (likely(detach))
-+ release = __ptrace_detach(current, tracee);
-+ write_unlock_irq(&tasklist_lock);
-+
-+ if (unlikely(release))
-+ release_task(tracee);
-+ else if (likely(detach))
-+ ptrace_detach_task(tracee, data);
-+}
-+
-+int ptrace_detach(struct task_struct *child, unsigned int data)
-+{
-+ if (!valid_signal(data))
-+ return -EIO;
-+
-+ ptrace_do_detach(child, data);
-+
-+ return 0;
-+}
-+
-+/*
-+ * Detach all tasks we were using ptrace on. Called with tasklist held
-+ * for writing, and returns with it held too. But note it can release
-+ * and reacquire the lock.
-+ */
-+void exit_ptrace(struct task_struct *tracer)
-+{
-+ bool locked = true;
-+
-+ for (;;) {
-+ struct task_struct *tracee = NULL;
-+
-+ if (!locked)
-+ read_lock(&tasklist_lock);
-+ if (!list_empty(&tracer->ptraced)) {
-+ tracee = list_first_entry(&tracer->ptraced,
-+ struct task_struct, ptrace_entry);
-+ get_task_struct(tracee);
-+ }
-+ if (!locked)
-+ read_unlock(&tasklist_lock);
-+ if (!tracee)
-+ break;
-+
-+ if (locked) {
-+ write_unlock_irq(&tasklist_lock);
-+ locked = false;
-+ }
-+ ptrace_do_detach(tracee, -1);
-+ put_task_struct(tracee);
-+ }
-+
-+ if (!locked)
-+ write_lock_irq(&tasklist_lock);
-+}
-+
-+static int ptrace_set_options(struct task_struct *tracee,
-+ struct utrace_engine *engine, long data)
-+{
-+ BUILD_BUG_ON(PTRACE_O_MASK & (PTRACE_O_SYSEMU | PTRACE_O_DETACHED));
-+
-+ ptrace_set_events(tracee, engine, data & PTRACE_O_MASK);
-+ return (data & ~PTRACE_O_MASK) ? -EINVAL : 0;
-+}
-+
-+static int ptrace_rw_siginfo(struct task_struct *tracee,
-+ struct ptrace_context *ctx,
-+ siginfo_t *info, bool write)
-+{
-+ unsigned long flags;
-+ int err;
-+
-+ switch (get_stop_event(ctx)) {
-+ case 0: /* jctl stop */
-+ return -EINVAL;
-+
-+ case PTRACE_EVENT_SIGNAL:
-+ err = -ESRCH;
-+ if (lock_task_sighand(tracee, &flags)) {
-+ if (likely(task_is_traced(tracee))) {
-+ if (write)
-+ *ctx->siginfo = *info;
-+ else
-+ *info = *ctx->siginfo;
-+ err = 0;
-+ }
-+ unlock_task_sighand(tracee, &flags);
-+ }
-+
-+ return err;
-+
-+ default:
-+ if (!write) {
-+ memset(info, 0, sizeof(*info));
-+ info->si_signo = SIGTRAP;
-+ info->si_code = ctx->stop_code & PTRACE_EVENT_MASK;
-+ info->si_pid = task_pid_vnr(tracee);
-+ info->si_uid = task_uid(tracee);
-+ }
-+
-+ return 0;
-+ }
-+}
-+
-+static void do_ptrace_notify_stop(struct ptrace_context *ctx,
-+ struct task_struct *tracee)
-+{
-+ /*
-+ * This can race with SIGKILL, but we borrow this race from
-+ * the old ptrace implementation. ->exit_code is only needed
-+ * for wait_task_stopped()->task_stopped_code(), we should
-+ * change it to use ptrace_context.
-+ */
-+ tracee->exit_code = ctx->stop_code & PTRACE_EVENT_MASK;
-+ WARN_ON(!tracee->exit_code);
-+
-+ read_lock(&tasklist_lock);
-+ /*
-+ * Don't want to allow preemption here, because
-+ * sys_ptrace() needs this task to be inactive.
-+ */
-+ preempt_disable();
-+ /*
-+ * It can be killed and then released by our subthread,
-+ * or ptrace_attach() has not completed yet.
-+ */
-+ if (task_ptrace(tracee))
-+ do_notify_parent_cldstop(tracee, CLD_TRAPPED);
-+ read_unlock(&tasklist_lock);
-+ preempt_enable_no_resched();
-+}
-+
-+void ptrace_notify_stop(struct task_struct *tracee)
-+{
-+ struct utrace_engine *engine = ptrace_lookup_engine(tracee);
-+
-+ if (IS_ERR(engine))
-+ return;
-+
-+ do_ptrace_notify_stop(ptrace_context(engine), tracee);
-+ utrace_engine_put(engine);
-+}
-+
-+static int ptrace_resume_action(struct task_struct *tracee,
-+ struct utrace_engine *engine, long request)
-+{
-+ struct ptrace_context *ctx = ptrace_context(engine);
-+ unsigned long events;
-+ int action;
-+
-+ ctx->options &= ~PTRACE_O_SYSEMU;
-+ events = engine->flags & ~UTRACE_EVENT_SYSCALL;
-+ action = UTRACE_RESUME;
-+
-+ switch (request) {
-+#ifdef PTRACE_SINGLEBLOCK
-+ case PTRACE_SINGLEBLOCK:
-+ if (unlikely(!arch_has_block_step()))
-+ return -EIO;
-+ action = UTRACE_BLOCKSTEP;
-+ events |= UTRACE_EVENT(SYSCALL_EXIT);
-+ break;
-+#endif
-+
-+#ifdef PTRACE_SINGLESTEP
-+ case PTRACE_SINGLESTEP:
-+ if (unlikely(!arch_has_single_step()))
-+ return -EIO;
-+ action = UTRACE_SINGLESTEP;
-+ events |= UTRACE_EVENT(SYSCALL_EXIT);
-+ break;
-+#endif
-+
-+#ifdef PTRACE_SYSEMU
-+ case PTRACE_SYSEMU_SINGLESTEP:
-+ if (unlikely(!arch_has_single_step()))
-+ return -EIO;
-+ action = UTRACE_SINGLESTEP;
-+ case PTRACE_SYSEMU:
-+ ctx->options |= PTRACE_O_SYSEMU;
-+ events |= UTRACE_EVENT(SYSCALL_ENTRY);
-+ break;
-+#endif
-+
-+ case PTRACE_SYSCALL:
-+ events |= UTRACE_EVENT_SYSCALL;
-+ break;
-+
-+ case PTRACE_CONT:
-+ break;
-+ default:
-+ return -EIO;
-+ }
-+
-+ if (events != engine->flags &&
-+ utrace_set_events(tracee, engine, events))
-+ return -ESRCH;
-+
-+ return action;
-+}
-+
-+static int ptrace_resume(struct task_struct *tracee,
-+ struct utrace_engine *engine,
-+ long request, long data)
-+{
-+ struct ptrace_context *ctx = ptrace_context(engine);
-+ int action;
-+
-+ if (!valid_signal(data))
-+ return -EIO;
-+
-+ action = ptrace_resume_action(tracee, engine, request);
-+ if (action < 0)
-+ return action;
-+
-+ switch (get_stop_event(ctx)) {
-+ case PTRACE_EVENT_VFORK:
-+ if (ctx->options & PTRACE_O_TRACEVFORKDONE) {
-+ set_stop_code(ctx, PTRACE_EVENT_VFORK_DONE);
-+ action = UTRACE_REPORT;
-+ }
-+ break;
-+
-+ case PTRACE_EVENT_EXEC:
-+ case PTRACE_EVENT_FORK:
-+ case PTRACE_EVENT_CLONE:
-+ case PTRACE_EVENT_VFORK_DONE:
-+ if (request == PTRACE_SYSCALL) {
-+ set_syscall_code(ctx);
-+ do_ptrace_notify_stop(ctx, tracee);
-+ return 0;
-+ }
-+
-+ if (action != UTRACE_RESUME) {
-+ /*
-+ * single-stepping. UTRACE_SIGNAL_REPORT will
-+ * synthesize a trap to follow the syscall insn.
-+ */
-+ ctx->signr = SIGTRAP;
-+ action = UTRACE_INTERRUPT;
-+ }
-+ break;
-+
-+ case PTRACE_EVENT_SYSCALL:
-+ if (data)
-+ send_sig_info(data, SEND_SIG_PRIV, tracee);
-+ break;
-+
-+ case PTRACE_EVENT_SIGNAL:
-+ ctx->signr = data;
-+ break;
-+ }
-+
-+ ctx->resume = action;
-+ ptrace_wake_up(tracee, engine, action, true);
-+ return 0;
-+}
-+
-+extern int ptrace_regset(struct task_struct *task, int req, unsigned int type,
-+ struct iovec *kiov);
-+
-+int ptrace_request(struct task_struct *child, long request,
-+ unsigned long addr, unsigned long data)
-+{
-+ struct utrace_engine *engine = ptrace_lookup_engine(child);
-+ siginfo_t siginfo;
-+ int ret;
-+
-+ if (unlikely(IS_ERR(engine)))
-+ return -ESRCH;
-+
-+ switch (request) {
-+ case PTRACE_PEEKTEXT:
-+ case PTRACE_PEEKDATA:
-+ ret = generic_ptrace_peekdata(child, addr, data);
-+ break;
-+ case PTRACE_POKETEXT:
-+ case PTRACE_POKEDATA:
-+ ret = generic_ptrace_pokedata(child, addr, data);
-+ break;
-+
-+#ifdef PTRACE_OLDSETOPTIONS
-+ case PTRACE_OLDSETOPTIONS:
-+#endif
-+ case PTRACE_SETOPTIONS:
-+ ret = ptrace_set_options(child, engine, data);
-+ break;
-+ case PTRACE_GETEVENTMSG:
-+ ret = put_user(ptrace_context(engine)->eventmsg,
-+ (unsigned long __user *) data);
-+ break;
-+
-+ case PTRACE_GETSIGINFO:
-+ ret = ptrace_rw_siginfo(child, ptrace_context(engine),
-+ &siginfo, false);
-+ if (!ret)
-+ ret = copy_siginfo_to_user((siginfo_t __user *) data,
-+ &siginfo);
-+ break;
-+
-+ case PTRACE_SETSIGINFO:
-+ if (copy_from_user(&siginfo, (siginfo_t __user *) data,
-+ sizeof siginfo))
-+ ret = -EFAULT;
-+ else
-+ ret = ptrace_rw_siginfo(child, ptrace_context(engine),
-+ &siginfo, true);
-+ break;
-+
-+ case PTRACE_DETACH: /* detach a process that was attached. */
-+ ret = ptrace_detach(child, data);
-+ break;
-+
-+ case PTRACE_KILL:
-+ /* Ugly historical behaviour. */
-+ if (task_is_traced(child))
-+ ptrace_resume(child, engine, PTRACE_CONT, SIGKILL);
-+ ret = 0;
-+ break;
-+
-+ case PTRACE_GETREGSET:
-+ case PTRACE_SETREGSET:
-+ {
-+ struct iovec kiov;
-+ struct iovec __user *uiov = (struct iovec __user *) data;
-+
-+ if (!access_ok(VERIFY_WRITE, uiov, sizeof(*uiov)))
-+ return -EFAULT;
-+
-+ if (__get_user(kiov.iov_base, &uiov->iov_base) ||
-+ __get_user(kiov.iov_len, &uiov->iov_len))
-+ return -EFAULT;
-+
-+ ret = ptrace_regset(child, request, addr, &kiov);
-+ if (!ret)
-+ ret = __put_user(kiov.iov_len, &uiov->iov_len);
-+ break;
-+ }
-+
-+ default:
-+ ret = ptrace_resume(child, engine, request, data);
-+ break;
-+ }
-+
-+ utrace_engine_put(engine);
-+ return ret;
-+}
-+
-+#if defined 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)
-+{
-+ struct utrace_engine *engine = ptrace_lookup_engine(child);
-+ compat_ulong_t __user *datap = compat_ptr(data);
-+ compat_ulong_t word;
-+ siginfo_t siginfo;
-+ int ret;
-+
-+ if (unlikely(IS_ERR(engine)))
-+ return -ESRCH;
-+
-+ 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)ptrace_context(engine)->eventmsg,
-+ datap);
-+ break;
-+
-+ case PTRACE_GETSIGINFO:
-+ ret = ptrace_rw_siginfo(child, ptrace_context(engine),
-+ &siginfo, false);
-+ if (!ret)
-+ ret = copy_siginfo_to_user32(
-+ (struct compat_siginfo __user *) datap,
-+ &siginfo);
-+ break;
-+
-+ case PTRACE_SETSIGINFO:
-+ memset(&siginfo, 0, sizeof siginfo);
-+ if (copy_siginfo_from_user32(
-+ &siginfo, (struct compat_siginfo __user *) datap))
-+ ret = -EFAULT;
-+ else
-+ ret = ptrace_rw_siginfo(child, ptrace_context(engine),
-+ &siginfo, true);
-+ break;
-+
-+ case PTRACE_GETREGSET:
-+ case PTRACE_SETREGSET:
-+ {
-+ struct iovec kiov;
-+ struct compat_iovec __user *uiov =
-+ (struct compat_iovec __user *) datap;
-+ compat_uptr_t ptr;
-+ compat_size_t len;
-+
-+ if (!access_ok(VERIFY_WRITE, uiov, sizeof(*uiov)))
-+ return -EFAULT;
-+
-+ if (__get_user(ptr, &uiov->iov_base) ||
-+ __get_user(len, &uiov->iov_len))
-+ return -EFAULT;
-+
-+ kiov.iov_base = compat_ptr(ptr);
-+ kiov.iov_len = len;
-+
-+ ret = ptrace_regset(child, request, addr, &kiov);
-+ if (!ret)
-+ ret = __put_user(kiov.iov_len, &uiov->iov_len);
-+ break;
-+ }
-+
-+ default:
-+ ret = ptrace_request(child, request, addr, data);
-+ }
-+
-+ utrace_engine_put(engine);
-+ return ret;
-+}
-+#endif /* CONFIG_COMPAT */
-diff --git a/kernel/ptrace.c b/kernel/ptrace.c
-index e275608..72ea65c 100644
---- a/kernel/ptrace.c
-+++ b/kernel/ptrace.c
-@@ -15,7 +15,6 @@
- #include <linux/highmem.h>
- #include <linux/pagemap.h>
- #include <linux/ptrace.h>
--#include <linux/utrace.h>
- #include <linux/security.h>
- #include <linux/signal.h>
- #include <linux/audit.h>
-@@ -24,7 +23,320 @@
- #include <linux/uaccess.h>
- #include <linux/regset.h>
-
-+int __ptrace_may_access(struct task_struct *task, unsigned int mode)
-+{
-+ const struct cred *cred = current_cred(), *tcred;
-+
-+ /* May we inspect the given task?
-+ * This check is used both for attaching with ptrace
-+ * and for allowing access to sensitive information in /proc.
-+ *
-+ * ptrace_attach denies several cases that /proc allows
-+ * because setting up the necessary parent/child relationship
-+ * or halting the specified task is impossible.
-+ */
-+ int dumpable = 0;
-+ /* Don't let security modules deny introspection */
-+ if (task == current)
-+ return 0;
-+ rcu_read_lock();
-+ tcred = __task_cred(task);
-+ if ((cred->uid != tcred->euid ||
-+ cred->uid != tcred->suid ||
-+ cred->uid != tcred->uid ||
-+ cred->gid != tcred->egid ||
-+ cred->gid != tcred->sgid ||
-+ cred->gid != tcred->gid) &&
-+ !capable(CAP_SYS_PTRACE)) {
-+ rcu_read_unlock();
-+ return -EPERM;
-+ }
-+ rcu_read_unlock();
-+ smp_rmb();
-+ if (task->mm)
-+ dumpable = get_dumpable(task->mm);
-+ if (!dumpable && !capable(CAP_SYS_PTRACE))
-+ return -EPERM;
-+
-+ return security_ptrace_access_check(task, mode);
-+}
-+
-+bool ptrace_may_access(struct task_struct *task, unsigned int mode)
-+{
-+ int err;
-+ task_lock(task);
-+ err = __ptrace_may_access(task, mode);
-+ task_unlock(task);
-+ return !err;
-+}
-+
-+/*
-+ * Called with irqs disabled, returns true if childs should reap themselves.
-+ */
-+static int ignoring_children(struct sighand_struct *sigh)
-+{
-+ int ret;
-+ spin_lock(&sigh->siglock);
-+ ret = (sigh->action[SIGCHLD-1].sa.sa_handler == SIG_IGN) ||
-+ (sigh->action[SIGCHLD-1].sa.sa_flags & SA_NOCLDWAIT);
-+ spin_unlock(&sigh->siglock);
-+ return ret;
-+}
-+
-+/*
-+ * Called with tasklist_lock held for writing.
-+ * Unlink a traced task, and clean it up if it was a traced zombie.
-+ * Return true if it needs to be reaped with release_task().
-+ * (We can't call release_task() here because we already hold tasklist_lock.)
-+ *
-+ * If it's a zombie, our attachedness prevented normal parent notification
-+ * or self-reaping. Do notification now if it would have happened earlier.
-+ * If it should reap itself, return true.
-+ *
-+ * If it's our own child, there is no notification to do. But if our normal
-+ * children self-reap, then this child was prevented by ptrace and we must
-+ * reap it now, in that case we must also wake up sub-threads sleeping in
-+ * do_wait().
-+ */
-+bool __ptrace_detach(struct task_struct *tracer, struct task_struct *p)
-+{
-+ __ptrace_unlink(p);
-+
-+ if (p->exit_state == EXIT_ZOMBIE) {
-+ if (!task_detached(p) && thread_group_empty(p)) {
-+ if (!same_thread_group(p->real_parent, tracer))
-+ do_notify_parent(p, p->exit_signal);
-+ else if (ignoring_children(tracer->sighand)) {
-+ __wake_up_parent(p, tracer);
-+ p->exit_signal = -1;
-+ }
-+ }
-+ if (task_detached(p)) {
-+ /* Mark it as in the process of being reaped. */
-+ p->exit_state = EXIT_DEAD;
-+ return true;
-+ }
-+ }
-+
-+ return false;
-+}
-+
-+int ptrace_readdata(struct task_struct *tsk, unsigned long src, char __user *dst, int len)
-+{
-+ int copied = 0;
-+
-+ while (len > 0) {
-+ char buf[128];
-+ int this_len, retval;
-+
-+ this_len = (len > sizeof(buf)) ? sizeof(buf) : len;
-+ retval = access_process_vm(tsk, src, buf, this_len, 0);
-+ if (!retval) {
-+ if (copied)
-+ break;
-+ return -EIO;
-+ }
-+ if (copy_to_user(dst, buf, retval))
-+ return -EFAULT;
-+ copied += retval;
-+ src += retval;
-+ dst += retval;
-+ len -= retval;
-+ }
-+ return copied;
-+}
-+
-+int ptrace_writedata(struct task_struct *tsk, char __user *src, unsigned long dst, int len)
-+{
-+ int copied = 0;
-+
-+ while (len > 0) {
-+ char buf[128];
-+ int this_len, retval;
-+
-+ this_len = (len > sizeof(buf)) ? sizeof(buf) : len;
-+ if (copy_from_user(buf, src, this_len))
-+ return -EFAULT;
-+ retval = access_process_vm(tsk, dst, buf, this_len, 1);
-+ if (!retval) {
-+ if (copied)
-+ break;
-+ return -EIO;
-+ }
-+ copied += retval;
-+ src += retval;
-+ dst += retval;
-+ len -= retval;
-+ }
-+ return copied;
-+}
-+
-+#ifdef CONFIG_HAVE_ARCH_TRACEHOOK
-+
-+static const struct user_regset *
-+find_regset(const struct user_regset_view *view, unsigned int type)
-+{
-+ const struct user_regset *regset;
-+ int n;
-+
-+ for (n = 0; n < view->n; ++n) {
-+ regset = view->regsets + n;
-+ if (regset->core_note_type == type)
-+ return regset;
-+ }
-+
-+ return NULL;
-+}
-+
-+int ptrace_regset(struct task_struct *task, int req, unsigned int type,
-+ struct iovec *kiov)
-+{
-+ const struct user_regset_view *view = task_user_regset_view(task);
-+ const struct user_regset *regset = find_regset(view, type);
-+ int regset_no;
-+
-+ if (!regset || (kiov->iov_len % regset->size) != 0)
-+ return -EINVAL;
-+
-+ regset_no = regset - view->regsets;
-+ kiov->iov_len = min(kiov->iov_len,
-+ (__kernel_size_t) (regset->n * regset->size));
-+
-+ if (req == PTRACE_GETREGSET)
-+ return copy_regset_to_user(task, view, regset_no, 0,
-+ kiov->iov_len, kiov->iov_base);
-+ else
-+ return copy_regset_from_user(task, view, regset_no, 0,
-+ kiov->iov_len, kiov->iov_base);
-+}
-+
-+#endif
-+
-+static struct task_struct *ptrace_get_task_struct(pid_t pid)
-+{
-+ struct task_struct *child;
-+
-+ rcu_read_lock();
-+ child = find_task_by_vpid(pid);
-+ if (child)
-+ get_task_struct(child);
-+ rcu_read_unlock();
-+
-+ if (!child)
-+ return ERR_PTR(-ESRCH);
-+ return child;
-+}
-+
-+#ifndef arch_ptrace_attach
-+#define arch_ptrace_attach(child) do { } while (0)
-+#endif
-+
-+SYSCALL_DEFINE4(ptrace, long, request, long, pid, unsigned long, addr,
-+ unsigned long, data)
-+{
-+ struct task_struct *child;
-+ long ret;
-+
-+ if (request == PTRACE_TRACEME) {
-+ ret = ptrace_traceme();
-+ if (!ret)
-+ arch_ptrace_attach(current);
-+ 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 < 0)
-+ goto out_put_task_struct;
-+
-+ ret = arch_ptrace(child, request, addr, data);
-+
-+ out_put_task_struct:
-+ put_task_struct(child);
-+ out:
-+ return ret;
-+}
-+
-+int generic_ptrace_peekdata(struct task_struct *tsk, unsigned long addr,
-+ unsigned long data)
-+{
-+ unsigned long tmp;
-+ int copied;
-+
-+ copied = access_process_vm(tsk, addr, &tmp, sizeof(tmp), 0);
-+ if (copied != sizeof(tmp))
-+ return -EIO;
-+ return put_user(tmp, (unsigned long __user *)data);
-+}
-+
-+int generic_ptrace_pokedata(struct task_struct *tsk, unsigned long addr,
-+ unsigned long data)
-+{
-+ int copied;
-+
-+ copied = access_process_vm(tsk, addr, &data, sizeof(data), 1);
-+ return (copied == sizeof(data)) ? 0 : -EIO;
-+}
-+
-+#if defined CONFIG_COMPAT
-+#include <linux/compat.h>
-+
-+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;
-+
-+ 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:
-+ return ret;
-+}
-+#endif /* CONFIG_COMPAT */
-+
-+#ifndef CONFIG_UTRACE
- /*
- * ptrace a task: make the debugger its new parent and
- * move it to the ptrace list.
-@@ -117,61 +429,6 @@ int ptrace_check_attach(struct task_stru
- return ret;
- }
-
--int __ptrace_may_access(struct task_struct *task, unsigned int mode)
--{
-- const struct cred *cred = current_cred(), *tcred;
--
-- /* May we inspect the given task?
-- * This check is used both for attaching with ptrace
-- * and for allowing access to sensitive information in /proc.
-- *
-- * ptrace_attach denies several cases that /proc allows
-- * because setting up the necessary parent/child relationship
-- * or halting the specified task is impossible.
-- */
-- int dumpable = 0;
-- /* Don't let security modules deny introspection */
-- if (task == current)
-- return 0;
-- rcu_read_lock();
-- tcred = __task_cred(task);
-- if ((cred->uid != tcred->euid ||
-- cred->uid != tcred->suid ||
-- cred->uid != tcred->uid ||
-- cred->gid != tcred->egid ||
-- cred->gid != tcred->sgid ||
-- cred->gid != tcred->gid) &&
-- !capable(CAP_SYS_PTRACE)) {
-- rcu_read_unlock();
-- return -EPERM;
-- }
-- rcu_read_unlock();
-- smp_rmb();
-- if (task->mm)
-- dumpable = get_dumpable(task->mm);
-- if (!dumpable && !capable(CAP_SYS_PTRACE))
-- return -EPERM;
--
-- return security_ptrace_access_check(task, mode);
--}
--
--bool ptrace_may_access(struct task_struct *task, unsigned int mode)
--{
-- int err;
-- task_lock(task);
-- err = __ptrace_may_access(task, mode);
-- task_unlock(task);
-- return !err;
--}
--
--/*
-- * For experimental use of utrace, exclude ptrace on the same task.
-- */
--static inline bool exclude_ptrace(struct task_struct *task)
--{
-- return unlikely(!!task_utrace_flags(task));
--}
--
- int ptrace_attach(struct task_struct *task)
- {
- int retval;
-@@ -195,8 +452,6 @@ int ptrace_attach(struct task_struct *ta
-
- task_lock(task);
- retval = __ptrace_may_access(task, PTRACE_MODE_ATTACH);
-- if (!retval && exclude_ptrace(task))
-- retval = -EBUSY;
- task_unlock(task);
- if (retval)
- goto unlock_creds;
-@@ -220,91 +475,37 @@ unlock_tasklist:
- write_unlock_irq(&tasklist_lock);
- unlock_creds:
- mutex_unlock(&task->signal->cred_guard_mutex);
--out:
-- return retval;
--}
--
--/**
-- * ptrace_traceme -- helper for PTRACE_TRACEME
-- *
-- * Performs checks and sets PT_PTRACED.
-- * Should be used by all ptrace implementations for PTRACE_TRACEME.
-- */
--int ptrace_traceme(void)
--{
-- int ret = -EPERM;
--
-- if (exclude_ptrace(current)) /* XXX locking */
-- return -EBUSY;
--
-- write_lock_irq(&tasklist_lock);
-- /* Are we already being traced? */
-- if (!current->ptrace) {
-- ret = security_ptrace_traceme(current->parent);
-- /*
-- * Check PF_EXITING to ensure ->real_parent has not passed
-- * exit_ptrace(). Otherwise we don't report the error but
-- * pretend ->real_parent untraces us right after return.
-- */
-- if (!ret && !(current->real_parent->flags & PF_EXITING)) {
-- current->ptrace = PT_PTRACED;
-- __ptrace_link(current, current->real_parent);
-- }
-- }
-- write_unlock_irq(&tasklist_lock);
--
-- return ret;
--}
--
--/*
-- * Called with irqs disabled, returns true if childs should reap themselves.
-- */
--static int ignoring_children(struct sighand_struct *sigh)
--{
-- int ret;
-- spin_lock(&sigh->siglock);
-- ret = (sigh->action[SIGCHLD-1].sa.sa_handler == SIG_IGN) ||
-- (sigh->action[SIGCHLD-1].sa.sa_flags & SA_NOCLDWAIT);
-- spin_unlock(&sigh->siglock);
-- return ret;
--}
--
--/*
-- * Called with tasklist_lock held for writing.
-- * Unlink a traced task, and clean it up if it was a traced zombie.
-- * Return true if it needs to be reaped with release_task().
-- * (We can't call release_task() here because we already hold tasklist_lock.)
-- *
-- * If it's a zombie, our attachedness prevented normal parent notification
-- * or self-reaping. Do notification now if it would have happened earlier.
-- * If it should reap itself, return true.
-+out:
-+ return retval;
-+}
-+
-+/**
-+ * ptrace_traceme -- helper for PTRACE_TRACEME
- *
-- * If it's our own child, there is no notification to do. But if our normal
-- * children self-reap, then this child was prevented by ptrace and we must
-- * reap it now, in that case we must also wake up sub-threads sleeping in
-- * do_wait().
-+ * Performs checks and sets PT_PTRACED.
-+ * Should be used by all ptrace implementations for PTRACE_TRACEME.
- */
--bool __ptrace_detach(struct task_struct *tracer, struct task_struct *p)
-+int ptrace_traceme(void)
- {
-- __ptrace_unlink(p);
-+ int ret = -EPERM;
-
-- if (p->exit_state == EXIT_ZOMBIE) {
-- if (!task_detached(p) && thread_group_empty(p)) {
-- if (!same_thread_group(p->real_parent, tracer))
-- do_notify_parent(p, p->exit_signal);
-- else if (ignoring_children(tracer->sighand)) {
-- __wake_up_parent(p, tracer);
-- p->exit_signal = -1;
-- }
-- }
-- if (task_detached(p)) {
-- /* Mark it as in the process of being reaped. */
-- p->exit_state = EXIT_DEAD;
-- return true;
-+ write_lock_irq(&tasklist_lock);
-+ /* Are we already being traced? */
-+ if (!current->ptrace) {
-+ ret = security_ptrace_traceme(current->parent);
-+ /*
-+ * Check PF_EXITING to ensure ->real_parent has not passed
-+ * exit_ptrace(). Otherwise we don't report the error but
-+ * pretend ->real_parent untraces us right after return.
-+ */
-+ if (!ret && !(current->real_parent->flags & PF_EXITING)) {
-+ current->ptrace = PT_PTRACED;
-+ __ptrace_link(current, current->real_parent);
- }
- }
-+ write_unlock_irq(&tasklist_lock);
-
-- return false;
-+ return ret;
- }
-
- int ptrace_detach(struct task_struct *child, unsigned int data)
-@@ -368,57 +569,7 @@ void exit_ptrace(struct task_struct *tra
- write_lock_irq(&tasklist_lock);
- }
-
--int ptrace_readdata(struct task_struct *tsk, unsigned long src, char __user *dst, int len)
--{
-- int copied = 0;
--
-- while (len > 0) {
-- char buf[128];
-- int this_len, retval;
--
-- this_len = (len > sizeof(buf)) ? sizeof(buf) : len;
-- retval = access_process_vm(tsk, src, buf, this_len, 0);
-- if (!retval) {
-- if (copied)
-- break;
-- return -EIO;
-- }
-- if (copy_to_user(dst, buf, retval))
-- return -EFAULT;
-- copied += retval;
-- src += retval;
-- dst += retval;
-- len -= retval;
-- }
-- return copied;
--}
--
--int ptrace_writedata(struct task_struct *tsk, char __user *src, unsigned long dst, int len)
--{
-- int copied = 0;
--
-- while (len > 0) {
-- char buf[128];
-- int this_len, retval;
--
-- this_len = (len > sizeof(buf)) ? sizeof(buf) : len;
-- if (copy_from_user(buf, src, this_len))
-- return -EFAULT;
-- retval = access_process_vm(tsk, dst, buf, this_len, 1);
-- if (!retval) {
-- if (copied)
-- break;
-- return -EIO;
-- }
-- copied += retval;
-- src += retval;
-- dst += retval;
-- len -= retval;
-- }
-- return copied;
--}
--
--static int ptrace_setoptions(struct task_struct *child, unsigned long data)
-+static int ptrace_setoptions(struct task_struct *child, long data)
- {
- child->ptrace &= ~PT_TRACE_MASK;
-
-@@ -533,47 +683,6 @@ static int ptrace_resume(struct task_str
- return 0;
- }
-
--#ifdef CONFIG_HAVE_ARCH_TRACEHOOK
--
--static const struct user_regset *
--find_regset(const struct user_regset_view *view, unsigned int type)
--{
-- const struct user_regset *regset;
-- int n;
--
-- for (n = 0; n < view->n; ++n) {
-- regset = view->regsets + n;
-- if (regset->core_note_type == type)
-- return regset;
-- }
--
-- return NULL;
--}
--
--static int ptrace_regset(struct task_struct *task, int req, unsigned int type,
-- struct iovec *kiov)
--{
-- const struct user_regset_view *view = task_user_regset_view(task);
-- const struct user_regset *regset = find_regset(view, type);
-- int regset_no;
--
-- if (!regset || (kiov->iov_len % regset->size) != 0)
-- return -EINVAL;
--
-- regset_no = regset - view->regsets;
-- kiov->iov_len = min(kiov->iov_len,
-- (__kernel_size_t) (regset->n * regset->size));
--
-- if (req == PTRACE_GETREGSET)
-- return copy_regset_to_user(task, view, regset_no, 0,
-- kiov->iov_len, kiov->iov_base);
-- else
-- return copy_regset_from_user(task, view, regset_no, 0,
-- kiov->iov_len, kiov->iov_base);
--}
--
--#endif
--
- int ptrace_request(struct task_struct *child, long request,
- unsigned long addr, unsigned long data)
- {
-@@ -689,91 +798,7 @@ int ptrace_request(struct task_struct *c
- return ret;
- }
-
--static struct task_struct *ptrace_get_task_struct(pid_t pid)
--{
-- struct task_struct *child;
--
-- rcu_read_lock();
-- child = find_task_by_vpid(pid);
-- if (child)
-- get_task_struct(child);
-- rcu_read_unlock();
--
-- if (!child)
-- return ERR_PTR(-ESRCH);
-- return child;
--}
--
--#ifndef arch_ptrace_attach
--#define arch_ptrace_attach(child) do { } while (0)
--#endif
--
--SYSCALL_DEFINE4(ptrace, long, request, long, pid, unsigned long, addr,
-- unsigned long, data)
--{
-- struct task_struct *child;
-- long ret;
--
-- if (request == PTRACE_TRACEME) {
-- ret = ptrace_traceme();
-- if (!ret)
-- arch_ptrace_attach(current);
-- 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 < 0)
-- goto out_put_task_struct;
--
-- ret = arch_ptrace(child, request, addr, data);
--
-- out_put_task_struct:
-- put_task_struct(child);
-- out:
-- return ret;
--}
--
--int generic_ptrace_peekdata(struct task_struct *tsk, unsigned long addr,
-- unsigned long data)
--{
-- unsigned long tmp;
-- int copied;
--
-- copied = access_process_vm(tsk, addr, &tmp, sizeof(tmp), 0);
-- if (copied != sizeof(tmp))
-- return -EIO;
-- return put_user(tmp, (unsigned long __user *)data);
--}
--
--int generic_ptrace_pokedata(struct task_struct *tsk, unsigned long addr,
-- unsigned long data)
--{
-- int copied;
--
-- copied = access_process_vm(tsk, addr, &data, sizeof(data), 1);
-- return (copied == sizeof(data)) ? 0 : -EIO;
--}
--
- #if defined 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)
- {
-@@ -851,42 +876,5 @@ int compat_ptrace_request(struct task_st
-
- return ret;
- }
--
--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;
--
-- 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:
-- return ret;
--}
- #endif /* CONFIG_COMPAT */
-+#endif /* CONFIG_UTRACE */
-diff --git a/kernel/utrace.c b/kernel/utrace.c
-index 26d6faf..37dce16 100644
---- a/kernel/utrace.c
-+++ b/kernel/utrace.c
-@@ -816,6 +816,22 @@ relock:
- spin_unlock_irq(&task->sighand->siglock);
- spin_unlock(&utrace->lock);
-
-+ /*
-+ * If ptrace is among the reasons for this stop, do its
-+ * notification now. This could not just be done in
-+ * ptrace's own event report callbacks because it has to
-+ * be done after we are in TASK_TRACED. This makes the
-+ * synchronization with ptrace_do_wait() work right.
-+ *
-+ * It's only because of the bad old overloading of the do_wait()
-+ * logic for handling ptrace stops that we need this special case
-+ * here. One day we will clean up ptrace so it does not need to
-+ * work this way. New things that are designed sensibly don't need
-+ * a wakeup that synchronizes with tasklist_lock and ->state, so
-+ * the proper utrace API does not try to support this weirdness.
-+ */
-+ ptrace_notify_stop(task);
-+
- schedule();
-
- utrace_finish_stop();