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-rw-r--r--arch/ia64/include/asm/ptrace.h4
-rw-r--r--arch/ia64/kernel/ptrace.c57
-rw-r--r--arch/um/include/asm/thread_info.h2
-rw-r--r--arch/um/kernel/exec.c2
-rw-r--r--arch/um/kernel/process.c2
-rw-r--r--arch/um/kernel/ptrace.c8
-rw-r--r--arch/um/kernel/signal.c4
-rw-r--r--arch/x86/kernel/step.c3
-rw-r--r--arch/xtensa/kernel/ptrace.c4
-rw-r--r--arch/xtensa/kernel/signal.c4
-rw-r--r--drivers/tty/tty_jobctrl.c4
-rw-r--r--include/linux/ptrace.h7
-rw-r--r--include/linux/sched.h10
-rw-r--r--include/linux/sched/jobctl.h8
-rw-r--r--include/linux/sched/signal.h20
-rw-r--r--include/linux/signal.h3
-rw-r--r--kernel/ptrace.c87
-rw-r--r--kernel/sched/core.c5
-rw-r--r--kernel/signal.c140
-rw-r--r--kernel/time/posix-cpu-timers.c6
20 files changed, 140 insertions, 240 deletions
diff --git a/arch/ia64/include/asm/ptrace.h b/arch/ia64/include/asm/ptrace.h
index a10a498eede1..402874489890 100644
--- a/arch/ia64/include/asm/ptrace.h
+++ b/arch/ia64/include/asm/ptrace.h
@@ -139,10 +139,6 @@ static inline long regs_return_value(struct pt_regs *regs)
#define arch_ptrace_stop_needed() \
(!test_thread_flag(TIF_RESTORE_RSE))
- extern void ptrace_attach_sync_user_rbs (struct task_struct *);
- #define arch_ptrace_attach(child) \
- ptrace_attach_sync_user_rbs(child)
-
#define arch_has_single_step() (1)
#define arch_has_block_step() (1)
diff --git a/arch/ia64/kernel/ptrace.c b/arch/ia64/kernel/ptrace.c
index 4fc6e38a8459..ab8aeb34d1d9 100644
--- a/arch/ia64/kernel/ptrace.c
+++ b/arch/ia64/kernel/ptrace.c
@@ -618,63 +618,6 @@ void ia64_sync_krbs(void)
}
/*
- * After PTRACE_ATTACH, a thread's register backing store area in user
- * space is assumed to contain correct data whenever the thread is
- * stopped. arch_ptrace_stop takes care of this on tracing stops.
- * But if the child was already stopped for job control when we attach
- * to it, then it might not ever get into ptrace_stop by the time we
- * want to examine the user memory containing the RBS.
- */
-void
-ptrace_attach_sync_user_rbs (struct task_struct *child)
-{
- int stopped = 0;
- struct unw_frame_info info;
-
- /*
- * If the child is in TASK_STOPPED, we need to change that to
- * TASK_TRACED momentarily while we operate on it. This ensures
- * that the child won't be woken up and return to user mode while
- * we are doing the sync. (It can only be woken up for SIGKILL.)
- */
-
- read_lock(&tasklist_lock);
- if (child->sighand) {
- spin_lock_irq(&child->sighand->siglock);
- if (READ_ONCE(child->__state) == TASK_STOPPED &&
- !test_and_set_tsk_thread_flag(child, TIF_RESTORE_RSE)) {
- set_notify_resume(child);
-
- WRITE_ONCE(child->__state, TASK_TRACED);
- stopped = 1;
- }
- spin_unlock_irq(&child->sighand->siglock);
- }
- read_unlock(&tasklist_lock);
-
- if (!stopped)
- return;
-
- unw_init_from_blocked_task(&info, child);
- do_sync_rbs(&info, ia64_sync_user_rbs);
-
- /*
- * Now move the child back into TASK_STOPPED if it should be in a
- * job control stop, so that SIGCONT can be used to wake it up.
- */
- read_lock(&tasklist_lock);
- if (child->sighand) {
- spin_lock_irq(&child->sighand->siglock);
- if (READ_ONCE(child->__state) == TASK_TRACED &&
- (child->signal->flags & SIGNAL_STOP_STOPPED)) {
- WRITE_ONCE(child->__state, TASK_STOPPED);
- }
- spin_unlock_irq(&child->sighand->siglock);
- }
- read_unlock(&tasklist_lock);
-}
-
-/*
* Write f32-f127 back to task->thread.fph if it has been modified.
*/
inline void
diff --git a/arch/um/include/asm/thread_info.h b/arch/um/include/asm/thread_info.h
index 1395cbd7e340..c7b4b49826a2 100644
--- a/arch/um/include/asm/thread_info.h
+++ b/arch/um/include/asm/thread_info.h
@@ -60,6 +60,7 @@ static inline struct thread_info *current_thread_info(void)
#define TIF_RESTORE_SIGMASK 7
#define TIF_NOTIFY_RESUME 8
#define TIF_SECCOMP 9 /* secure computing */
+#define TIF_SINGLESTEP 10 /* single stepping userspace */
#define _TIF_SYSCALL_TRACE (1 << TIF_SYSCALL_TRACE)
#define _TIF_SIGPENDING (1 << TIF_SIGPENDING)
@@ -68,5 +69,6 @@ static inline struct thread_info *current_thread_info(void)
#define _TIF_MEMDIE (1 << TIF_MEMDIE)
#define _TIF_SYSCALL_AUDIT (1 << TIF_SYSCALL_AUDIT)
#define _TIF_SECCOMP (1 << TIF_SECCOMP)
+#define _TIF_SINGLESTEP (1 << TIF_SINGLESTEP)
#endif
diff --git a/arch/um/kernel/exec.c b/arch/um/kernel/exec.c
index c85e40c72779..58938d75871a 100644
--- a/arch/um/kernel/exec.c
+++ b/arch/um/kernel/exec.c
@@ -43,7 +43,7 @@ void start_thread(struct pt_regs *regs, unsigned long eip, unsigned long esp)
{
PT_REGS_IP(regs) = eip;
PT_REGS_SP(regs) = esp;
- current->ptrace &= ~PT_DTRACE;
+ clear_thread_flag(TIF_SINGLESTEP);
#ifdef SUBARCH_EXECVE1
SUBARCH_EXECVE1(regs->regs);
#endif
diff --git a/arch/um/kernel/process.c b/arch/um/kernel/process.c
index 181cc9aafb25..80b90b1276a1 100644
--- a/arch/um/kernel/process.c
+++ b/arch/um/kernel/process.c
@@ -336,7 +336,7 @@ int singlestepping(void * t)
{
struct task_struct *task = t ? t : current;
- if (!(task->ptrace & PT_DTRACE))
+ if (!test_thread_flag(TIF_SINGLESTEP))
return 0;
if (task->thread.singlestep_syscall)
diff --git a/arch/um/kernel/ptrace.c b/arch/um/kernel/ptrace.c
index bfaf6ab1ac03..5154b27de580 100644
--- a/arch/um/kernel/ptrace.c
+++ b/arch/um/kernel/ptrace.c
@@ -11,7 +11,7 @@
void user_enable_single_step(struct task_struct *child)
{
- child->ptrace |= PT_DTRACE;
+ set_tsk_thread_flag(child, TIF_SINGLESTEP);
child->thread.singlestep_syscall = 0;
#ifdef SUBARCH_SET_SINGLESTEPPING
@@ -21,7 +21,7 @@ void user_enable_single_step(struct task_struct *child)
void user_disable_single_step(struct task_struct *child)
{
- child->ptrace &= ~PT_DTRACE;
+ clear_tsk_thread_flag(child, TIF_SINGLESTEP);
child->thread.singlestep_syscall = 0;
#ifdef SUBARCH_SET_SINGLESTEPPING
@@ -120,7 +120,7 @@ static void send_sigtrap(struct uml_pt_regs *regs, int error_code)
}
/*
- * XXX Check PT_DTRACE vs TIF_SINGLESTEP for singlestepping check and
+ * XXX Check TIF_SINGLESTEP for singlestepping check and
* PT_PTRACED vs TIF_SYSCALL_TRACE for syscall tracing check
*/
int syscall_trace_enter(struct pt_regs *regs)
@@ -144,7 +144,7 @@ void syscall_trace_leave(struct pt_regs *regs)
audit_syscall_exit(regs);
/* Fake a debug trap */
- if (ptraced & PT_DTRACE)
+ if (test_thread_flag(TIF_SINGLESTEP))
send_sigtrap(&regs->regs, 0);
if (!test_thread_flag(TIF_SYSCALL_TRACE))
diff --git a/arch/um/kernel/signal.c b/arch/um/kernel/signal.c
index 88cd9b5c1b74..ae4658f576ab 100644
--- a/arch/um/kernel/signal.c
+++ b/arch/um/kernel/signal.c
@@ -53,7 +53,7 @@ static void handle_signal(struct ksignal *ksig, struct pt_regs *regs)
unsigned long sp;
int err;
- if ((current->ptrace & PT_DTRACE) && (current->ptrace & PT_PTRACED))
+ if (test_thread_flag(TIF_SINGLESTEP) && (current->ptrace & PT_PTRACED))
singlestep = 1;
/* Did we come from a system call? */
@@ -128,7 +128,7 @@ void do_signal(struct pt_regs *regs)
* on the host. The tracing thread will check this flag and
* PTRACE_SYSCALL if necessary.
*/
- if (current->ptrace & PT_DTRACE)
+ if (test_thread_flag(TIF_SINGLESTEP))
current->thread.singlestep_syscall =
is_syscall(PT_REGS_IP(&current->thread.regs));
diff --git a/arch/x86/kernel/step.c b/arch/x86/kernel/step.c
index 0f3c307b37b3..8e2b2552b5ee 100644
--- a/arch/x86/kernel/step.c
+++ b/arch/x86/kernel/step.c
@@ -180,8 +180,7 @@ void set_task_blockstep(struct task_struct *task, bool on)
*
* NOTE: this means that set/clear TIF_BLOCKSTEP is only safe if
* task is current or it can't be running, otherwise we can race
- * with __switch_to_xtra(). We rely on ptrace_freeze_traced() but
- * PTRACE_KILL is not safe.
+ * with __switch_to_xtra(). We rely on ptrace_freeze_traced().
*/
local_irq_disable();
debugctl = get_debugctlmsr();
diff --git a/arch/xtensa/kernel/ptrace.c b/arch/xtensa/kernel/ptrace.c
index 22cdaa6729d3..f29477162ede 100644
--- a/arch/xtensa/kernel/ptrace.c
+++ b/arch/xtensa/kernel/ptrace.c
@@ -224,12 +224,12 @@ const struct user_regset_view *task_user_regset_view(struct task_struct *task)
void user_enable_single_step(struct task_struct *child)
{
- child->ptrace |= PT_SINGLESTEP;
+ set_tsk_thread_flag(child, TIF_SINGLESTEP);
}
void user_disable_single_step(struct task_struct *child)
{
- child->ptrace &= ~PT_SINGLESTEP;
+ clear_tsk_thread_flag(child, TIF_SINGLESTEP);
}
/*
diff --git a/arch/xtensa/kernel/signal.c b/arch/xtensa/kernel/signal.c
index c9ffd42db873..876d5df157ed 100644
--- a/arch/xtensa/kernel/signal.c
+++ b/arch/xtensa/kernel/signal.c
@@ -472,7 +472,7 @@ static void do_signal(struct pt_regs *regs)
/* Set up the stack frame */
ret = setup_frame(&ksig, sigmask_to_save(), regs);
signal_setup_done(ret, &ksig, 0);
- if (current->ptrace & PT_SINGLESTEP)
+ if (test_thread_flag(TIF_SINGLESTEP))
task_pt_regs(current)->icountlevel = 1;
return;
@@ -498,7 +498,7 @@ static void do_signal(struct pt_regs *regs)
/* If there's no signal to deliver, we just restore the saved mask. */
restore_saved_sigmask();
- if (current->ptrace & PT_SINGLESTEP)
+ if (test_thread_flag(TIF_SINGLESTEP))
task_pt_regs(current)->icountlevel = 1;
return;
}
diff --git a/drivers/tty/tty_jobctrl.c b/drivers/tty/tty_jobctrl.c
index 80b86a7992b5..0d04287da098 100644
--- a/drivers/tty/tty_jobctrl.c
+++ b/drivers/tty/tty_jobctrl.c
@@ -215,8 +215,8 @@ int tty_signal_session_leader(struct tty_struct *tty, int exit_session)
spin_unlock_irq(&p->sighand->siglock);
continue;
}
- __group_send_sig_info(SIGHUP, SEND_SIG_PRIV, p);
- __group_send_sig_info(SIGCONT, SEND_SIG_PRIV, p);
+ send_signal_locked(SIGHUP, SEND_SIG_PRIV, p, PIDTYPE_TGID);
+ send_signal_locked(SIGCONT, SEND_SIG_PRIV, p, PIDTYPE_TGID);
put_pid(p->signal->tty_old_pgrp); /* A noop */
spin_lock(&tty->ctrl.lock);
tty_pgrp = get_pid(tty->ctrl.pgrp);
diff --git a/include/linux/ptrace.h b/include/linux/ptrace.h
index db4509587d2c..c952c5ba8fab 100644
--- a/include/linux/ptrace.h
+++ b/include/linux/ptrace.h
@@ -30,7 +30,6 @@ extern int ptrace_access_vm(struct task_struct *tsk, unsigned long addr,
#define PT_SEIZED 0x00010000 /* SEIZE used, enable new behavior */
#define PT_PTRACED 0x00000001
-#define PT_DTRACE 0x00000002 /* delayed trace (used on um) */
#define PT_OPT_FLAG_SHIFT 3
/* PT_TRACE_* event enable flags */
@@ -47,12 +46,6 @@ extern int ptrace_access_vm(struct task_struct *tsk, unsigned long addr,
#define PT_EXITKILL (PTRACE_O_EXITKILL << PT_OPT_FLAG_SHIFT)
#define PT_SUSPEND_SECCOMP (PTRACE_O_SUSPEND_SECCOMP << PT_OPT_FLAG_SHIFT)
-/* single stepping state bits (used on ARM and PA-RISC) */
-#define PT_SINGLESTEP_BIT 31
-#define PT_SINGLESTEP (1<<PT_SINGLESTEP_BIT)
-#define PT_BLOCKSTEP_BIT 30
-#define PT_BLOCKSTEP (1<<PT_BLOCKSTEP_BIT)
-
extern long arch_ptrace(struct task_struct *child, long request,
unsigned long addr, unsigned long data);
extern int ptrace_readdata(struct task_struct *tsk, unsigned long src, char __user *dst, int len);
diff --git a/include/linux/sched.h b/include/linux/sched.h
index b89c8571187b..c46f3a63b758 100644
--- a/include/linux/sched.h
+++ b/include/linux/sched.h
@@ -103,7 +103,7 @@ struct task_group;
/* Convenience macros for the sake of set_current_state: */
#define TASK_KILLABLE (TASK_WAKEKILL | TASK_UNINTERRUPTIBLE)
#define TASK_STOPPED (TASK_WAKEKILL | __TASK_STOPPED)
-#define TASK_TRACED (TASK_WAKEKILL | __TASK_TRACED)
+#define TASK_TRACED __TASK_TRACED
#define TASK_IDLE (TASK_UNINTERRUPTIBLE | TASK_NOLOAD)
@@ -118,11 +118,9 @@ struct task_group;
#define task_is_running(task) (READ_ONCE((task)->__state) == TASK_RUNNING)
-#define task_is_traced(task) ((READ_ONCE(task->__state) & __TASK_TRACED) != 0)
-
-#define task_is_stopped(task) ((READ_ONCE(task->__state) & __TASK_STOPPED) != 0)
-
-#define task_is_stopped_or_traced(task) ((READ_ONCE(task->__state) & (__TASK_STOPPED | __TASK_TRACED)) != 0)
+#define task_is_traced(task) ((READ_ONCE(task->jobctl) & JOBCTL_TRACED) != 0)
+#define task_is_stopped(task) ((READ_ONCE(task->jobctl) & JOBCTL_STOPPED) != 0)
+#define task_is_stopped_or_traced(task) ((READ_ONCE(task->jobctl) & (JOBCTL_STOPPED | JOBCTL_TRACED)) != 0)
/*
* Special states are those that do not use the normal wait-loop pattern. See
diff --git a/include/linux/sched/jobctl.h b/include/linux/sched/jobctl.h
index fa067de9f1a9..68876d0a7ef9 100644
--- a/include/linux/sched/jobctl.h
+++ b/include/linux/sched/jobctl.h
@@ -19,6 +19,10 @@ struct task_struct;
#define JOBCTL_TRAPPING_BIT 21 /* switching to TRACED */
#define JOBCTL_LISTENING_BIT 22 /* ptracer is listening for events */
#define JOBCTL_TRAP_FREEZE_BIT 23 /* trap for cgroup freezer */
+#define JOBCTL_PTRACE_FROZEN_BIT 24 /* frozen for ptrace */
+
+#define JOBCTL_STOPPED_BIT 26 /* do_signal_stop() */
+#define JOBCTL_TRACED_BIT 27 /* ptrace_stop() */
#define JOBCTL_STOP_DEQUEUED (1UL << JOBCTL_STOP_DEQUEUED_BIT)
#define JOBCTL_STOP_PENDING (1UL << JOBCTL_STOP_PENDING_BIT)
@@ -28,6 +32,10 @@ struct task_struct;
#define JOBCTL_TRAPPING (1UL << JOBCTL_TRAPPING_BIT)
#define JOBCTL_LISTENING (1UL << JOBCTL_LISTENING_BIT)
#define JOBCTL_TRAP_FREEZE (1UL << JOBCTL_TRAP_FREEZE_BIT)
+#define JOBCTL_PTRACE_FROZEN (1UL << JOBCTL_PTRACE_FROZEN_BIT)
+
+#define JOBCTL_STOPPED (1UL << JOBCTL_STOPPED_BIT)
+#define JOBCTL_TRACED (1UL << JOBCTL_TRACED_BIT)
#define JOBCTL_TRAP_MASK (JOBCTL_TRAP_STOP | JOBCTL_TRAP_NOTIFY)
#define JOBCTL_PENDING_MASK (JOBCTL_STOP_PENDING | JOBCTL_TRAP_MASK)
diff --git a/include/linux/sched/signal.h b/include/linux/sched/signal.h
index 20ed5ba2bde4..cafbe03eed01 100644
--- a/include/linux/sched/signal.h
+++ b/include/linux/sched/signal.h
@@ -294,8 +294,10 @@ static inline int kernel_dequeue_signal(void)
static inline void kernel_signal_stop(void)
{
spin_lock_irq(&current->sighand->siglock);
- if (current->jobctl & JOBCTL_STOP_DEQUEUED)
+ if (current->jobctl & JOBCTL_STOP_DEQUEUED) {
+ current->jobctl |= JOBCTL_STOPPED;
set_special_state(TASK_STOPPED);
+ }
spin_unlock_irq(&current->sighand->siglock);
schedule();
@@ -444,13 +446,23 @@ extern void calculate_sigpending(void);
extern void signal_wake_up_state(struct task_struct *t, unsigned int state);
-static inline void signal_wake_up(struct task_struct *t, bool resume)
+static inline void signal_wake_up(struct task_struct *t, bool fatal)
{
- signal_wake_up_state(t, resume ? TASK_WAKEKILL : 0);
+ unsigned int state = 0;
+ if (fatal && !(t->jobctl & JOBCTL_PTRACE_FROZEN)) {
+ t->jobctl &= ~(JOBCTL_STOPPED | JOBCTL_TRACED);
+ state = TASK_WAKEKILL | __TASK_TRACED;
+ }
+ signal_wake_up_state(t, state);
}
static inline void ptrace_signal_wake_up(struct task_struct *t, bool resume)
{
- signal_wake_up_state(t, resume ? __TASK_TRACED : 0);
+ unsigned int state = 0;
+ if (resume) {
+ t->jobctl &= ~JOBCTL_TRACED;
+ state = __TASK_TRACED;
+ }
+ signal_wake_up_state(t, state);
}
void task_join_group_stop(struct task_struct *task);
diff --git a/include/linux/signal.h b/include/linux/signal.h
index a6db6f2ae113..3b98e7a28538 100644
--- a/include/linux/signal.h
+++ b/include/linux/signal.h
@@ -282,7 +282,8 @@ extern int do_send_sig_info(int sig, struct kernel_siginfo *info,
struct task_struct *p, enum pid_type type);
extern int group_send_sig_info(int sig, struct kernel_siginfo *info,
struct task_struct *p, enum pid_type type);
-extern int __group_send_sig_info(int, struct kernel_siginfo *, struct task_struct *);
+extern int send_signal_locked(int sig, struct kernel_siginfo *info,
+ struct task_struct *p, enum pid_type type);
extern int sigprocmask(int, sigset_t *, sigset_t *);
extern void set_current_blocked(sigset_t *);
extern void __set_current_blocked(const sigset_t *);
diff --git a/kernel/ptrace.c b/kernel/ptrace.c
index 49c29baf9907..156a99283b11 100644
--- a/kernel/ptrace.c
+++ b/kernel/ptrace.c
@@ -185,7 +185,12 @@ static bool looks_like_a_spurious_pid(struct task_struct *task)
return true;
}
-/* Ensure that nothing can wake it up, even SIGKILL */
+/*
+ * Ensure that nothing can wake it up, even SIGKILL
+ *
+ * A task is switched to this state while a ptrace operation is in progress;
+ * such that the ptrace operation is uninterruptible.
+ */
static bool ptrace_freeze_traced(struct task_struct *task)
{
bool ret = false;
@@ -197,7 +202,7 @@ static bool ptrace_freeze_traced(struct task_struct *task)
spin_lock_irq(&task->sighand->siglock);
if (task_is_traced(task) && !looks_like_a_spurious_pid(task) &&
!__fatal_signal_pending(task)) {
- WRITE_ONCE(task->__state, __TASK_TRACED);
+ task->jobctl |= JOBCTL_PTRACE_FROZEN;
ret = true;
}
spin_unlock_irq(&task->sighand->siglock);
@@ -207,23 +212,21 @@ static bool ptrace_freeze_traced(struct task_struct *task)
static void ptrace_unfreeze_traced(struct task_struct *task)
{
- if (READ_ONCE(task->__state) != __TASK_TRACED)
- return;
-
- WARN_ON(!task->ptrace || task->parent != current);
+ unsigned long flags;
/*
- * PTRACE_LISTEN can allow ptrace_trap_notify to wake us up remotely.
- * Recheck state under the lock to close this race.
+ * The child may be awake and may have cleared
+ * JOBCTL_PTRACE_FROZEN (see ptrace_resume). The child will
+ * not set JOBCTL_PTRACE_FROZEN or enter __TASK_TRACED anew.
*/
- spin_lock_irq(&task->sighand->siglock);
- if (READ_ONCE(task->__state) == __TASK_TRACED) {
- if (__fatal_signal_pending(task))
+ if (lock_task_sighand(task, &flags)) {
+ task->jobctl &= ~JOBCTL_PTRACE_FROZEN;
+ if (__fatal_signal_pending(task)) {
+ task->jobctl &= ~TASK_TRACED;
wake_up_state(task, __TASK_TRACED);
- else
- WRITE_ONCE(task->__state, TASK_TRACED);
+ }
+ unlock_task_sighand(task, &flags);
}
- spin_unlock_irq(&task->sighand->siglock);
}
/**
@@ -256,7 +259,6 @@ static int ptrace_check_attach(struct task_struct *child, bool ignore_state)
*/
read_lock(&tasklist_lock);
if (child->ptrace && child->parent == current) {
- WARN_ON(READ_ONCE(child->__state) == __TASK_TRACED);
/*
* child->sighand can't be NULL, release_task()
* does ptrace_unlink() before __exit_signal().
@@ -266,17 +268,9 @@ static int ptrace_check_attach(struct task_struct *child, bool ignore_state)
}
read_unlock(&tasklist_lock);
- if (!ret && !ignore_state) {
- if (!wait_task_inactive(child, __TASK_TRACED)) {
- /*
- * This can only happen if may_ptrace_stop() fails and
- * ptrace_stop() changes ->state back to TASK_RUNNING,
- * so we should not worry about leaking __TASK_TRACED.
- */
- WARN_ON(READ_ONCE(child->__state) == __TASK_TRACED);
- ret = -ESRCH;
- }
- }
+ if (!ret && !ignore_state &&
+ WARN_ON_ONCE(!wait_task_inactive(child, __TASK_TRACED)))
+ ret = -ESRCH;
return ret;
}
@@ -475,8 +469,10 @@ static int ptrace_attach(struct task_struct *task, long request,
* in and out of STOPPED are protected by siglock.
*/
if (task_is_stopped(task) &&
- task_set_jobctl_pending(task, JOBCTL_TRAP_STOP | JOBCTL_TRAPPING))
+ task_set_jobctl_pending(task, JOBCTL_TRAP_STOP | JOBCTL_TRAPPING)) {
+ task->jobctl &= ~JOBCTL_STOPPED;
signal_wake_up_state(task, __TASK_STOPPED);
+ }
spin_unlock(&task->sighand->siglock);
@@ -846,8 +842,6 @@ static long ptrace_get_rseq_configuration(struct task_struct *task,
static int ptrace_resume(struct task_struct *child, long request,
unsigned long data)
{
- bool need_siglock;
-
if (!valid_signal(data))
return -EIO;
@@ -883,18 +877,12 @@ static int ptrace_resume(struct task_struct *child, long request,
* Note that we need siglock even if ->exit_code == data and/or this
* status was not reported yet, the new status must not be cleared by
* wait_task_stopped() after resume.
- *
- * If data == 0 we do not care if wait_task_stopped() reports the old
- * status and clears the code too; this can't race with the tracee, it
- * takes siglock after resume.
*/
- need_siglock = data && !thread_group_empty(current);
- if (need_siglock)
- spin_lock_irq(&child->sighand->siglock);
+ spin_lock_irq(&child->sighand->siglock);
child->exit_code = data;
+ child->jobctl &= ~JOBCTL_TRACED;
wake_up_state(child, __TASK_TRACED);
- if (need_siglock)
- spin_unlock_irq(&child->sighand->siglock);
+ spin_unlock_irq(&child->sighand->siglock);
return 0;
}
@@ -1230,9 +1218,8 @@ int ptrace_request(struct task_struct *child, long request,
return ptrace_resume(child, request, data);
case PTRACE_KILL:
- if (child->exit_state) /* already dead */
- return 0;
- return ptrace_resume(child, request, SIGKILL);
+ send_sig_info(SIGKILL, SEND_SIG_NOINFO, child);
+ return 0;
#ifdef CONFIG_HAVE_ARCH_TRACEHOOK
case PTRACE_GETREGSET:
@@ -1279,10 +1266,6 @@ int ptrace_request(struct task_struct *child, long request,
return ret;
}
-#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)
{
@@ -1291,8 +1274,6 @@ SYSCALL_DEFINE4(ptrace, long, request, long, pid, unsigned long, addr,
if (request == PTRACE_TRACEME) {
ret = ptrace_traceme();
- if (!ret)
- arch_ptrace_attach(current);
goto out;
}
@@ -1304,12 +1285,6 @@ SYSCALL_DEFINE4(ptrace, long, request, long, pid, unsigned long, addr,
if (request == PTRACE_ATTACH || request == PTRACE_SEIZE) {
ret = ptrace_attach(child, request, addr, data);
- /*
- * Some architectures need to do book-keeping after
- * a ptrace attach.
- */
- if (!ret)
- arch_ptrace_attach(child);
goto out_put_task_struct;
}
@@ -1449,12 +1424,6 @@ COMPAT_SYSCALL_DEFINE4(ptrace, compat_long_t, request, compat_long_t, pid,
if (request == PTRACE_ATTACH || request == PTRACE_SEIZE) {
ret = ptrace_attach(child, request, addr, data);
- /*
- * Some architectures need to do book-keeping after
- * a ptrace attach.
- */
- if (!ret)
- arch_ptrace_attach(child);
goto out_put_task_struct;
}
diff --git a/kernel/sched/core.c b/kernel/sched/core.c
index 696c6490bd5b..bfa7452ca92e 100644
--- a/kernel/sched/core.c
+++ b/kernel/sched/core.c
@@ -6353,10 +6353,7 @@ static void __sched notrace __schedule(unsigned int sched_mode)
/*
* We must load prev->state once (task_struct::state is volatile), such
- * that:
- *
- * - we form a control dependency vs deactivate_task() below.
- * - ptrace_{,un}freeze_traced() can change ->state underneath us.
+ * that we form a control dependency vs deactivate_task() below.
*/
prev_state = READ_ONCE(prev->__state);
if (!(sched_mode & SM_MASK_PREEMPT) && prev_state) {
diff --git a/kernel/signal.c b/kernel/signal.c
index e43bc2a692f5..edb1dc9b00dc 100644
--- a/kernel/signal.c
+++ b/kernel/signal.c
@@ -762,7 +762,10 @@ still_pending:
*/
void signal_wake_up_state(struct task_struct *t, unsigned int state)
{
+ lockdep_assert_held(&t->sighand->siglock);
+
set_tsk_thread_flag(t, TIF_SIGPENDING);
+
/*
* TASK_WAKEKILL also means wake it up in the stopped/traced/killable
* case. We don't check t->state here because there is a race with it
@@ -884,7 +887,7 @@ static int check_kill_permission(int sig, struct kernel_siginfo *info,
static void ptrace_trap_notify(struct task_struct *t)
{
WARN_ON_ONCE(!(t->ptrace & PT_SEIZED));
- assert_spin_locked(&t->sighand->siglock);
+ lockdep_assert_held(&t->sighand->siglock);
task_set_jobctl_pending(t, JOBCTL_TRAP_NOTIFY);
ptrace_signal_wake_up(t, t->jobctl & JOBCTL_LISTENING);
@@ -930,9 +933,10 @@ static bool prepare_signal(int sig, struct task_struct *p, bool force)
for_each_thread(p, t) {
flush_sigqueue_mask(&flush, &t->pending);
task_clear_jobctl_pending(t, JOBCTL_STOP_PENDING);
- if (likely(!(t->ptrace & PT_SEIZED)))
+ if (likely(!(t->ptrace & PT_SEIZED))) {
+ t->jobctl &= ~JOBCTL_STOPPED;
wake_up_state(t, __TASK_STOPPED);
- else
+ } else
ptrace_trap_notify(t);
}
@@ -1071,15 +1075,15 @@ static inline bool legacy_queue(struct sigpending *signals, int sig)
return (sig < SIGRTMIN) && sigismember(&signals->signal, sig);
}
-static int __send_signal(int sig, struct kernel_siginfo *info, struct task_struct *t,
- enum pid_type type, bool force)
+static int __send_signal_locked(int sig, struct kernel_siginfo *info,
+ struct task_struct *t, enum pid_type type, bool force)
{
struct sigpending *pending;
struct sigqueue *q;
int override_rlimit;
int ret = 0, result;
- assert_spin_locked(&t->sighand->siglock);
+ lockdep_assert_held(&t->sighand->siglock);
result = TRACE_SIGNAL_IGNORED;
if (!prepare_signal(sig, t, force))
@@ -1212,8 +1216,8 @@ static inline bool has_si_pid_and_uid(struct kernel_siginfo *info)
return ret;
}
-static int send_signal(int sig, struct kernel_siginfo *info, struct task_struct *t,
- enum pid_type type)
+int send_signal_locked(int sig, struct kernel_siginfo *info,
+ struct task_struct *t, enum pid_type type)
{
/* Should SIGKILL or SIGSTOP be received by a pid namespace init? */
bool force = false;
@@ -1245,7 +1249,7 @@ static int send_signal(int sig, struct kernel_siginfo *info, struct task_struct
force = true;
}
}
- return __send_signal(sig, info, t, type, force);
+ return __send_signal_locked(sig, info, t, type, force);
}
static void print_fatal_signal(int signr)
@@ -1281,12 +1285,6 @@ static int __init setup_print_fatal_signals(char *str)
__setup("print-fatal-signals=", setup_print_fatal_signals);
-int
-__group_send_sig_info(int sig, struct kernel_siginfo *info, struct task_struct *p)
-{
- return send_signal(sig, info, p, PIDTYPE_TGID);
-}
-
int do_send_sig_info(int sig, struct kernel_siginfo *info, struct task_struct *p,
enum pid_type type)
{
@@ -1294,7 +1292,7 @@ int do_send_sig_info(int sig, struct kernel_siginfo *info, struct task_struct *p
int ret = -ESRCH;
if (lock_task_sighand(p, &flags)) {
- ret = send_signal(sig, info, p, type);
+ ret = send_signal_locked(sig, info, p, type);
unlock_task_sighand(p, &flags);
}
@@ -1347,7 +1345,7 @@ force_sig_info_to_task(struct kernel_siginfo *info, struct task_struct *t,
if (action->sa.sa_handler == SIG_DFL &&
(!t->ptrace || (handler == HANDLER_EXIT)))
t->signal->flags &= ~SIGNAL_UNKILLABLE;
- ret = send_signal(sig, info, t, PIDTYPE_PID);
+ ret = send_signal_locked(sig, info, t, PIDTYPE_PID);
spin_unlock_irqrestore(&t->sighand->siglock, flags);
return ret;
@@ -1567,7 +1565,7 @@ int kill_pid_usb_asyncio(int sig, int errno, sigval_t addr,
if (sig) {
if (lock_task_sighand(p, &flags)) {
- ret = __send_signal(sig, &info, p, PIDTYPE_TGID, false);
+ ret = __send_signal_locked(sig, &info, p, PIDTYPE_TGID, false);
unlock_task_sighand(p, &flags);
} else
ret = -ESRCH;
@@ -2114,7 +2112,7 @@ bool do_notify_parent(struct task_struct *tsk, int sig)
* parent's namespaces.
*/
if (valid_signal(sig) && sig)
- __send_signal(sig, &info, tsk->parent, PIDTYPE_TGID, false);
+ __send_signal_locked(sig, &info, tsk->parent, PIDTYPE_TGID, false);
__wake_up_parent(tsk, tsk->parent);
spin_unlock_irqrestore(&psig->siglock, flags);
@@ -2184,7 +2182,7 @@ static void do_notify_parent_cldstop(struct task_struct *tsk,
spin_lock_irqsave(&sighand->siglock, flags);
if (sighand->action[SIGCHLD-1].sa.sa_handler != SIG_IGN &&
!(sighand->action[SIGCHLD-1].sa.sa_flags & SA_NOCLDSTOP))
- __group_send_sig_info(SIGCHLD, &info, parent);
+ send_signal_locked(SIGCHLD, &info, parent, PIDTYPE_TGID);
/*
* Even if SIGCHLD is not generated, we must wake up wait4 calls.
*/
@@ -2204,13 +2202,12 @@ static void do_notify_parent_cldstop(struct task_struct *tsk,
* with. If the code did not stop because the tracer is gone,
* the stop signal remains unchanged unless clear_code.
*/
-static int ptrace_stop(int exit_code, int why, int clear_code,
- unsigned long message, kernel_siginfo_t *info)
+static int ptrace_stop(int exit_code, int why, unsigned long message,
+ kernel_siginfo_t *info)
__releases(&current->sighand->siglock)
__acquires(&current->sighand->siglock)
{
bool gstop_done = false;
- bool read_code = true;
if (arch_ptrace_stop_needed()) {
/*
@@ -2227,10 +2224,16 @@ static int ptrace_stop(int exit_code, int why, int clear_code,
}
/*
- * schedule() will not sleep if there is a pending signal that
- * can awaken the task.
+ * After this point ptrace_signal_wake_up or signal_wake_up
+ * will clear TASK_TRACED if ptrace_unlink happens or a fatal
+ * signal comes in. Handle previous ptrace_unlinks and fatal
+ * signals here to prevent ptrace_stop sleeping in schedule.
*/
+ if (!current->ptrace || __fatal_signal_pending(current))
+ return exit_code;
+
set_special_state(TASK_TRACED);
+ current->jobctl |= JOBCTL_TRACED;
/*
* We're committing to trapping. TRACED should be visible before
@@ -2276,54 +2279,33 @@ static int ptrace_stop(int exit_code, int why, int clear_code,
spin_unlock_irq(&current->sighand->siglock);
read_lock(&tasklist_lock);
- if (likely(current->ptrace)) {
- /*
- * Notify parents of the stop.
- *
- * While ptraced, there are two parents - the ptracer and
- * the real_parent of the group_leader. The ptracer should
- * know about every stop while the real parent is only
- * interested in the completion of group stop. The states
- * for the two don't interact with each other. Notify
- * separately unless they're gonna be duplicates.
- */
+ /*
+ * Notify parents of the stop.
+ *
+ * While ptraced, there are two parents - the ptracer and
+ * the real_parent of the group_leader. The ptracer should
+ * know about every stop while the real parent is only
+ * interested in the completion of group stop. The states
+ * for the two don't interact with each other. Notify
+ * separately unless they're gonna be duplicates.
+ */
+ if (current->ptrace)
do_notify_parent_cldstop(current, true, why);
- if (gstop_done && ptrace_reparented(current))
- do_notify_parent_cldstop(current, false, why);
+ if (gstop_done && (!current->ptrace || ptrace_reparented(current)))
+ do_notify_parent_cldstop(current, false, why);
- /*
- * Don't want to allow preemption here, because
- * sys_ptrace() needs this task to be inactive.
- *
- * XXX: implement read_unlock_no_resched().
- */
- preempt_disable();
- read_unlock(&tasklist_lock);
- cgroup_enter_frozen();
- preempt_enable_no_resched();
- freezable_schedule();
- cgroup_leave_frozen(true);
- } else {
- /*
- * By the time we got the lock, our tracer went away.
- * Don't drop the lock yet, another tracer may come.
- *
- * If @gstop_done, the ptracer went away between group stop
- * completion and here. During detach, it would have set
- * JOBCTL_STOP_PENDING on us and we'll re-enter
- * TASK_STOPPED in do_signal_stop() on return, so notifying
- * the real parent of the group stop completion is enough.
- */
- if (gstop_done)
- do_notify_parent_cldstop(current, false, why);
-
- /* tasklist protects us from ptrace_freeze_traced() */
- __set_current_state(TASK_RUNNING);
- read_code = false;
- if (clear_code)
- exit_code = 0;
- read_unlock(&tasklist_lock);
- }
+ /*
+ * Don't want to allow preemption here, because
+ * sys_ptrace() needs this task to be inactive.
+ *
+ * XXX: implement read_unlock_no_resched().
+ */
+ preempt_disable();
+ read_unlock(&tasklist_lock);
+ cgroup_enter_frozen();
+ preempt_enable_no_resched();
+ freezable_schedule();
+ cgroup_leave_frozen(true);
/*
* We are back. Now reacquire the siglock before touching
@@ -2331,14 +2313,13 @@ static int ptrace_stop(int exit_code, int why, int clear_code,
* any signal-sending on another CPU that wants to examine it.
*/
spin_lock_irq(&current->sighand->siglock);
- if (read_code)
- exit_code = current->exit_code;
+ exit_code = current->exit_code;
current->last_siginfo = NULL;
current->ptrace_message = 0;
current->exit_code = 0;
/* LISTENING can be set only during STOP traps, clear it */
- current->jobctl &= ~JOBCTL_LISTENING;
+ current->jobctl &= ~(JOBCTL_LISTENING | JOBCTL_PTRACE_FROZEN);
/*
* Queued signals ignored us while we were stopped for tracing.
@@ -2360,7 +2341,7 @@ static int ptrace_do_notify(int signr, int exit_code, int why, unsigned long mes
info.si_uid = from_kuid_munged(current_user_ns(), current_uid());
/* Let the debugger run. */
- return ptrace_stop(exit_code, why, 1, message, &info);
+ return ptrace_stop(exit_code, why, message, &info);
}
int ptrace_notify(int exit_code, unsigned long message)
@@ -2471,6 +2452,7 @@ static bool do_signal_stop(int signr)
if (task_participate_group_stop(current))
notify = CLD_STOPPED;
+ current->jobctl |= JOBCTL_STOPPED;
set_special_state(TASK_STOPPED);
spin_unlock_irq(&current->sighand->siglock);
@@ -2532,7 +2514,7 @@ static void do_jobctl_trap(void)
CLD_STOPPED, 0);
} else {
WARN_ON_ONCE(!signr);
- ptrace_stop(signr, CLD_STOPPED, 0, 0, NULL);
+ ptrace_stop(signr, CLD_STOPPED, 0, NULL);
}
}
@@ -2585,7 +2567,7 @@ static int ptrace_signal(int signr, kernel_siginfo_t *info, enum pid_type type)
* comment in dequeue_signal().
*/
current->jobctl |= JOBCTL_STOP_DEQUEUED;
- signr = ptrace_stop(signr, CLD_TRAPPED, 0, 0, info);
+ signr = ptrace_stop(signr, CLD_TRAPPED, 0, info);
/* We're back. Did the debugger cancel the sig? */
if (signr == 0)
@@ -2612,7 +2594,7 @@ static int ptrace_signal(int signr, kernel_siginfo_t *info, enum pid_type type)
/* If the (new) signal is now blocked, requeue it. */
if (sigismember(&current->blocked, signr) ||
fatal_signal_pending(current)) {
- send_signal(signr, info, current, type);
+ send_signal_locked(signr, info, current, type);
signr = 0;
}
@@ -4807,7 +4789,7 @@ void kdb_send_sig(struct task_struct *t, int sig)
"the deadlock.\n");
return;
}
- ret = send_signal(sig, SEND_SIG_PRIV, t, PIDTYPE_PID);
+ ret = send_signal_locked(sig, SEND_SIG_PRIV, t, PIDTYPE_PID);
spin_unlock(&t->sighand->siglock);
if (ret)
kdb_printf("Fail to deliver Signal %d to process %d.\n",
diff --git a/kernel/time/posix-cpu-timers.c b/kernel/time/posix-cpu-timers.c
index 0a97193984db..cb925e8ef9a8 100644
--- a/kernel/time/posix-cpu-timers.c
+++ b/kernel/time/posix-cpu-timers.c
@@ -870,7 +870,7 @@ static inline void check_dl_overrun(struct task_struct *tsk)
{
if (tsk->dl.dl_overrun) {
tsk->dl.dl_overrun = 0;
- __group_send_sig_info(SIGXCPU, SEND_SIG_PRIV, tsk);
+ send_signal_locked(SIGXCPU, SEND_SIG_PRIV, tsk, PIDTYPE_TGID);
}
}
@@ -884,7 +884,7 @@ static bool check_rlimit(u64 time, u64 limit, int signo, bool rt, bool hard)
rt ? "RT" : "CPU", hard ? "hard" : "soft",
current->comm, task_pid_nr(current));
}
- __group_send_sig_info(signo, SEND_SIG_PRIV, current);
+ send_signal_locked(signo, SEND_SIG_PRIV, current, PIDTYPE_TGID);
return true;
}
@@ -958,7 +958,7 @@ static void check_cpu_itimer(struct task_struct *tsk, struct cpu_itimer *it,
trace_itimer_expire(signo == SIGPROF ?
ITIMER_PROF : ITIMER_VIRTUAL,
task_tgid(tsk), cur_time);
- __group_send_sig_info(signo, SEND_SIG_PRIV, tsk);
+ send_signal_locked(signo, SEND_SIG_PRIV, tsk, PIDTYPE_TGID);
}
if (it->expires && it->expires < *expires)
generated by cgit v1.2.3-58-ga151 (git 2.39.0) at 2024-11-24 23:49:07 +0000