*/
#include <linux/slab.h>
-#include <linux/module.h>
+#include <linux/export.h>
#include <linux/init.h>
#include <linux/sched.h>
#include <linux/fs.h>
#include <linux/tty.h>
#include <linux/binfmts.h>
+#include <linux/coredump.h>
#include <linux/security.h>
#include <linux/syscalls.h>
#include <linux/ptrace.h>
#include <linux/freezer.h>
#include <linux/pid_namespace.h>
#include <linux/nsproxy.h>
+#include <linux/user_namespace.h>
+#include <linux/uprobes.h>
+#include <linux/compat.h>
+#include <linux/cn_proc.h>
#define CREATE_TRACE_POINTS
#include <trace/events/signal.h>
#include <asm/uaccess.h>
#include <asm/unistd.h>
#include <asm/siginfo.h>
+#include <asm/cacheflush.h>
#include "audit.h" /* audit_signal_info() */
/*
(handler == SIG_DFL && sig_kernel_ignore(sig));
}
-static int sig_task_ignored(struct task_struct *t, int sig,
- int from_ancestor_ns)
+static int sig_task_ignored(struct task_struct *t, int sig, bool force)
{
void __user *handler;
handler = sig_handler(t, sig);
if (unlikely(t->signal->flags & SIGNAL_UNKILLABLE) &&
- handler == SIG_DFL && !from_ancestor_ns)
+ handler == SIG_DFL && !force)
return 1;
return sig_handler_ignored(handler, sig);
}
-static int sig_ignored(struct task_struct *t, int sig, int from_ancestor_ns)
+static int sig_ignored(struct task_struct *t, int sig, bool force)
{
/*
* Blocked signals are never ignored, since the
if (sigismember(&t->blocked, sig) || sigismember(&t->real_blocked, sig))
return 0;
- if (!sig_task_ignored(t, sig, from_ancestor_ns))
+ if (!sig_task_ignored(t, sig, force))
return 0;
/*
* Tracers may want to know about even ignored signals.
*/
- return !tracehook_consider_ignored_signal(t, sig);
+ return !t->ptrace;
}
/*
static int recalc_sigpending_tsk(struct task_struct *t)
{
- if ((t->group_stop & GROUP_STOP_PENDING) ||
+ if ((t->jobctl & JOBCTL_PENDING_MASK) ||
PENDING(&t->pending, &t->blocked) ||
PENDING(&t->signal->shared_pending, &t->blocked)) {
set_tsk_thread_flag(t, TIF_SIGPENDING);
void recalc_sigpending(void)
{
- if (unlikely(tracehook_force_sigpending()))
- set_thread_flag(TIF_SIGPENDING);
- else if (!recalc_sigpending_tsk(current) && !freezing(current))
+ if (!recalc_sigpending_tsk(current) && !freezing(current))
clear_thread_flag(TIF_SIGPENDING);
}
#define SYNCHRONOUS_MASK \
(sigmask(SIGSEGV) | sigmask(SIGBUS) | sigmask(SIGILL) | \
- sigmask(SIGTRAP) | sigmask(SIGFPE))
+ sigmask(SIGTRAP) | sigmask(SIGFPE) | sigmask(SIGSYS))
int next_signal(struct sigpending *pending, sigset_t *mask)
{
}
/**
- * task_clear_group_stop_trapping - clear group stop trapping bit
+ * task_set_jobctl_pending - set jobctl pending bits
* @task: target task
+ * @mask: pending bits to set
*
- * If GROUP_STOP_TRAPPING is set, a ptracer is waiting for us. Clear it
- * and wake up the ptracer. Note that we don't need any further locking.
- * @task->siglock guarantees that @task->parent points to the ptracer.
+ * Clear @mask from @task->jobctl. @mask must be subset of
+ * %JOBCTL_PENDING_MASK | %JOBCTL_STOP_CONSUME | %JOBCTL_STOP_SIGMASK |
+ * %JOBCTL_TRAPPING. If stop signo is being set, the existing signo is
+ * cleared. If @task is already being killed or exiting, this function
+ * becomes noop.
+ *
+ * CONTEXT:
+ * Must be called with @task->sighand->siglock held.
+ *
+ * RETURNS:
+ * %true if @mask is set, %false if made noop because @task was dying.
+ */
+bool task_set_jobctl_pending(struct task_struct *task, unsigned int mask)
+{
+ BUG_ON(mask & ~(JOBCTL_PENDING_MASK | JOBCTL_STOP_CONSUME |
+ JOBCTL_STOP_SIGMASK | JOBCTL_TRAPPING));
+ BUG_ON((mask & JOBCTL_TRAPPING) && !(mask & JOBCTL_PENDING_MASK));
+
+ if (unlikely(fatal_signal_pending(task) || (task->flags & PF_EXITING)))
+ return false;
+
+ if (mask & JOBCTL_STOP_SIGMASK)
+ task->jobctl &= ~JOBCTL_STOP_SIGMASK;
+
+ task->jobctl |= mask;
+ return true;
+}
+
+/**
+ * task_clear_jobctl_trapping - clear jobctl trapping bit
+ * @task: target task
+ *
+ * If JOBCTL_TRAPPING is set, a ptracer is waiting for us to enter TRACED.
+ * Clear it and wake up the ptracer. Note that we don't need any further
+ * locking. @task->siglock guarantees that @task->parent points to the
+ * ptracer.
*
* CONTEXT:
* Must be called with @task->sighand->siglock held.
*/
-static void task_clear_group_stop_trapping(struct task_struct *task)
+void task_clear_jobctl_trapping(struct task_struct *task)
{
- if (unlikely(task->group_stop & GROUP_STOP_TRAPPING)) {
- task->group_stop &= ~GROUP_STOP_TRAPPING;
- __wake_up_sync_key(&task->parent->signal->wait_chldexit,
- TASK_UNINTERRUPTIBLE, 1, task);
+ if (unlikely(task->jobctl & JOBCTL_TRAPPING)) {
+ task->jobctl &= ~JOBCTL_TRAPPING;
+ wake_up_bit(&task->jobctl, JOBCTL_TRAPPING_BIT);
}
}
/**
- * task_clear_group_stop_pending - clear pending group stop
+ * task_clear_jobctl_pending - clear jobctl pending bits
* @task: target task
+ * @mask: pending bits to clear
+ *
+ * Clear @mask from @task->jobctl. @mask must be subset of
+ * %JOBCTL_PENDING_MASK. If %JOBCTL_STOP_PENDING is being cleared, other
+ * STOP bits are cleared together.
*
- * Clear group stop states for @task.
+ * If clearing of @mask leaves no stop or trap pending, this function calls
+ * task_clear_jobctl_trapping().
*
* CONTEXT:
* Must be called with @task->sighand->siglock held.
*/
-void task_clear_group_stop_pending(struct task_struct *task)
+void task_clear_jobctl_pending(struct task_struct *task, unsigned int mask)
{
- task->group_stop &= ~(GROUP_STOP_PENDING | GROUP_STOP_CONSUME |
- GROUP_STOP_DEQUEUED);
+ BUG_ON(mask & ~JOBCTL_PENDING_MASK);
+
+ if (mask & JOBCTL_STOP_PENDING)
+ mask |= JOBCTL_STOP_CONSUME | JOBCTL_STOP_DEQUEUED;
+
+ task->jobctl &= ~mask;
+
+ if (!(task->jobctl & JOBCTL_PENDING_MASK))
+ task_clear_jobctl_trapping(task);
}
/**
* task_participate_group_stop - participate in a group stop
* @task: task participating in a group stop
*
- * @task has GROUP_STOP_PENDING set and is participating in a group stop.
+ * @task has %JOBCTL_STOP_PENDING set and is participating in a group stop.
* Group stop states are cleared and the group stop count is consumed if
- * %GROUP_STOP_CONSUME was set. If the consumption completes the group
+ * %JOBCTL_STOP_CONSUME was set. If the consumption completes the group
* stop, the appropriate %SIGNAL_* flags are set.
*
* CONTEXT:
static bool task_participate_group_stop(struct task_struct *task)
{
struct signal_struct *sig = task->signal;
- bool consume = task->group_stop & GROUP_STOP_CONSUME;
+ bool consume = task->jobctl & JOBCTL_STOP_CONSUME;
- WARN_ON_ONCE(!(task->group_stop & GROUP_STOP_PENDING));
+ WARN_ON_ONCE(!(task->jobctl & JOBCTL_STOP_PENDING));
- task_clear_group_stop_pending(task);
+ task_clear_jobctl_pending(task, JOBCTL_STOP_PENDING);
if (!consume)
return false;
if (force_default || ka->sa.sa_handler != SIG_IGN)
ka->sa.sa_handler = SIG_DFL;
ka->sa.sa_flags = 0;
+#ifdef __ARCH_HAS_SA_RESTORER
+ ka->sa.sa_restorer = NULL;
+#endif
sigemptyset(&ka->sa.sa_mask);
ka++;
}
return 1;
if (handler != SIG_IGN && handler != SIG_DFL)
return 0;
- return !tracehook_consider_fatal_signal(tsk, sig);
+ /* if ptraced, let the tracer determine */
+ return !tsk->ptrace;
}
/*
* is to alert stop-signal processing code when another
* processor has come along and cleared the flag.
*/
- current->group_stop |= GROUP_STOP_DEQUEUED;
+ current->jobctl |= JOBCTL_STOP_DEQUEUED;
}
if ((info->si_code & __SI_MASK) == __SI_TIMER && info->si_sys_private) {
/*
* No need to set need_resched since signal event passing
* goes through ->blocked
*/
-void signal_wake_up(struct task_struct *t, int resume)
+void signal_wake_up_state(struct task_struct *t, unsigned int state)
{
- unsigned int mask;
-
set_tsk_thread_flag(t, TIF_SIGPENDING);
-
/*
- * For SIGKILL, we want to wake it up in the stopped/traced/killable
+ * 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
* executing another processor and just now entering stopped state.
* By using wake_up_state, we ensure the process will wake up and
* handle its death signal.
*/
- mask = TASK_INTERRUPTIBLE;
- if (resume)
- mask |= TASK_WAKEKILL;
- if (!wake_up_state(t, mask))
+ if (!wake_up_state(t, state | TASK_INTERRUPTIBLE))
kick_process(t);
}
const struct cred *cred = current_cred();
const struct cred *tcred = __task_cred(t);
- if (cred->user->user_ns == tcred->user->user_ns &&
- (cred->euid == tcred->suid ||
- cred->euid == tcred->uid ||
- cred->uid == tcred->suid ||
- cred->uid == tcred->uid))
+ if (uid_eq(cred->euid, tcred->suid) ||
+ uid_eq(cred->euid, tcred->uid) ||
+ uid_eq(cred->uid, tcred->suid) ||
+ uid_eq(cred->uid, tcred->uid))
return 1;
- if (ns_capable(tcred->user->user_ns, CAP_KILL))
+ if (ns_capable(tcred->user_ns, CAP_KILL))
return 1;
return 0;
return security_task_kill(t, info, sig, 0);
}
+/**
+ * ptrace_trap_notify - schedule trap to notify ptracer
+ * @t: tracee wanting to notify tracer
+ *
+ * This function schedules sticky ptrace trap which is cleared on the next
+ * TRAP_STOP to notify ptracer of an event. @t must have been seized by
+ * ptracer.
+ *
+ * If @t is running, STOP trap will be taken. If trapped for STOP and
+ * ptracer is listening for events, tracee is woken up so that it can
+ * re-trap for the new event. If trapped otherwise, STOP trap will be
+ * eventually taken without returning to userland after the existing traps
+ * are finished by PTRACE_CONT.
+ *
+ * CONTEXT:
+ * Must be called with @task->sighand->siglock held.
+ */
+static void ptrace_trap_notify(struct task_struct *t)
+{
+ WARN_ON_ONCE(!(t->ptrace & PT_SEIZED));
+ assert_spin_locked(&t->sighand->siglock);
+
+ task_set_jobctl_pending(t, JOBCTL_TRAP_NOTIFY);
+ ptrace_signal_wake_up(t, t->jobctl & JOBCTL_LISTENING);
+}
+
/*
* Handle magic process-wide effects of stop/continue signals. Unlike
* the signal actions, these happen immediately at signal-generation
* Returns true if the signal should be actually delivered, otherwise
* it should be dropped.
*/
-static int prepare_signal(int sig, struct task_struct *p, int from_ancestor_ns)
+static bool prepare_signal(int sig, struct task_struct *p, bool force)
{
struct signal_struct *signal = p->signal;
struct task_struct *t;
- if (unlikely(signal->flags & SIGNAL_GROUP_EXIT)) {
+ if (signal->flags & (SIGNAL_GROUP_EXIT | SIGNAL_GROUP_COREDUMP)) {
+ if (signal->flags & SIGNAL_GROUP_COREDUMP)
+ return sig == SIGKILL;
/*
* The process is in the middle of dying, nothing to do.
*/
rm_from_queue(SIG_KERNEL_STOP_MASK, &signal->shared_pending);
t = p;
do {
- task_clear_group_stop_pending(t);
+ task_clear_jobctl_pending(t, JOBCTL_STOP_PENDING);
rm_from_queue(SIG_KERNEL_STOP_MASK, &t->pending);
- wake_up_state(t, __TASK_STOPPED);
+ if (likely(!(t->ptrace & PT_SEIZED)))
+ wake_up_state(t, __TASK_STOPPED);
+ else
+ ptrace_trap_notify(t);
} while_each_thread(p, t);
/*
}
}
- return !sig_ignored(p, sig, from_ancestor_ns);
+ return !sig_ignored(p, sig, force);
}
/*
if (sig_fatal(p, sig) &&
!(signal->flags & (SIGNAL_UNKILLABLE | SIGNAL_GROUP_EXIT)) &&
!sigismember(&t->real_blocked, sig) &&
- (sig == SIGKILL ||
- !tracehook_consider_fatal_signal(t, sig))) {
+ (sig == SIGKILL || !t->ptrace)) {
/*
* This signal will be fatal to the whole group.
*/
signal->group_stop_count = 0;
t = p;
do {
- task_clear_group_stop_pending(t);
+ task_clear_jobctl_pending(t, JOBCTL_PENDING_MASK);
sigaddset(&t->pending.signal, SIGKILL);
signal_wake_up(t, 1);
} while_each_thread(p, t);
return (sig < SIGRTMIN) && sigismember(&signals->signal, sig);
}
+#ifdef CONFIG_USER_NS
+static inline void userns_fixup_signal_uid(struct siginfo *info, struct task_struct *t)
+{
+ if (current_user_ns() == task_cred_xxx(t, user_ns))
+ return;
+
+ if (SI_FROMKERNEL(info))
+ return;
+
+ rcu_read_lock();
+ info->si_uid = from_kuid_munged(task_cred_xxx(t, user_ns),
+ make_kuid(current_user_ns(), info->si_uid));
+ rcu_read_unlock();
+}
+#else
+static inline void userns_fixup_signal_uid(struct siginfo *info, struct task_struct *t)
+{
+ return;
+}
+#endif
+
static int __send_signal(int sig, struct siginfo *info, struct task_struct *t,
int group, int from_ancestor_ns)
{
struct sigpending *pending;
struct sigqueue *q;
int override_rlimit;
-
- trace_signal_generate(sig, info, t);
+ int ret = 0, result;
assert_spin_locked(&t->sighand->siglock);
- if (!prepare_signal(sig, t, from_ancestor_ns))
- return 0;
+ result = TRACE_SIGNAL_IGNORED;
+ if (!prepare_signal(sig, t,
+ from_ancestor_ns || (info == SEND_SIG_FORCED)))
+ goto ret;
pending = group ? &t->signal->shared_pending : &t->pending;
/*
* exactly one non-rt signal, so that we can get more
* detailed information about the cause of the signal.
*/
+ result = TRACE_SIGNAL_ALREADY_PENDING;
if (legacy_queue(pending, sig))
- return 0;
+ goto ret;
+
+ result = TRACE_SIGNAL_DELIVERED;
/*
* fast-pathed signals for kernel-internal things like SIGSTOP
* or SIGKILL.
q->info.si_code = SI_USER;
q->info.si_pid = task_tgid_nr_ns(current,
task_active_pid_ns(t));
- q->info.si_uid = current_uid();
+ q->info.si_uid = from_kuid_munged(current_user_ns(), current_uid());
break;
case (unsigned long) SEND_SIG_PRIV:
q->info.si_signo = sig;
q->info.si_pid = 0;
break;
}
+
+ userns_fixup_signal_uid(&q->info, t);
+
} else if (!is_si_special(info)) {
if (sig >= SIGRTMIN && info->si_code != SI_USER) {
/*
* signal was rt and sent by user using something
* other than kill().
*/
- trace_signal_overflow_fail(sig, group, info);
- return -EAGAIN;
+ result = TRACE_SIGNAL_OVERFLOW_FAIL;
+ ret = -EAGAIN;
+ goto ret;
} else {
/*
* This is a silent loss of information. We still
* send the signal, but the *info bits are lost.
*/
- trace_signal_lose_info(sig, group, info);
+ result = TRACE_SIGNAL_LOSE_INFO;
}
}
signalfd_notify(t, sig);
sigaddset(&pending->signal, sig);
complete_signal(sig, t, group);
- return 0;
+ret:
+ trace_signal_generate(sig, info, t, group, result);
+ return ret;
}
static int send_signal(int sig, struct siginfo *info, struct task_struct *t,
return __send_signal(sig, info, t, group, from_ancestor_ns);
}
-static void print_fatal_signal(struct pt_regs *regs, int signr)
+static void print_fatal_signal(int signr)
{
- printk("%s/%d: potentially unexpected fatal signal %d.\n",
- current->comm, task_pid_nr(current), signr);
+ struct pt_regs *regs = signal_pt_regs();
+ printk(KERN_INFO "potentially unexpected fatal signal %d.\n", signr);
#if defined(__i386__) && !defined(__arch_um__)
- printk("code at %08lx: ", regs->ip);
+ printk(KERN_INFO "code at %08lx: ", regs->ip);
{
int i;
for (i = 0; i < 16; i++) {
if (get_user(insn, (unsigned char *)(regs->ip + i)))
break;
- printk("%02x ", insn);
+ printk(KERN_CONT "%02x ", insn);
}
}
+ printk(KERN_CONT "\n");
#endif
- printk("\n");
preempt_disable();
show_regs(regs);
preempt_enable();
p->signal->group_stop_count = 0;
while_each_thread(p, t) {
- task_clear_group_stop_pending(t);
+ task_clear_jobctl_pending(t, JOBCTL_PENDING_MASK);
count++;
/* Don't bother with already dead threads */
return error;
}
+static int kill_as_cred_perm(const struct cred *cred,
+ struct task_struct *target)
+{
+ const struct cred *pcred = __task_cred(target);
+ if (!uid_eq(cred->euid, pcred->suid) && !uid_eq(cred->euid, pcred->uid) &&
+ !uid_eq(cred->uid, pcred->suid) && !uid_eq(cred->uid, pcred->uid))
+ return 0;
+ return 1;
+}
+
/* like kill_pid_info(), but doesn't use uid/euid of "current" */
-int kill_pid_info_as_uid(int sig, struct siginfo *info, struct pid *pid,
- uid_t uid, uid_t euid, u32 secid)
+int kill_pid_info_as_cred(int sig, struct siginfo *info, struct pid *pid,
+ const struct cred *cred, u32 secid)
{
int ret = -EINVAL;
struct task_struct *p;
- const struct cred *pcred;
unsigned long flags;
if (!valid_signal(sig))
ret = -ESRCH;
goto out_unlock;
}
- pcred = __task_cred(p);
- if (si_fromuser(info) &&
- euid != pcred->suid && euid != pcred->uid &&
- uid != pcred->suid && uid != pcred->uid) {
+ if (si_fromuser(info) && !kill_as_cred_perm(cred, p)) {
ret = -EPERM;
goto out_unlock;
}
rcu_read_unlock();
return ret;
}
-EXPORT_SYMBOL_GPL(kill_pid_info_as_uid);
+EXPORT_SYMBOL_GPL(kill_pid_info_as_cred);
/*
* kill_something_info() interprets pid in interesting ways just like kill(2).
int sig = q->info.si_signo;
struct sigpending *pending;
unsigned long flags;
- int ret;
+ int ret, result;
BUG_ON(!(q->flags & SIGQUEUE_PREALLOC));
goto ret;
ret = 1; /* the signal is ignored */
- if (!prepare_signal(sig, t, 0))
+ result = TRACE_SIGNAL_IGNORED;
+ if (!prepare_signal(sig, t, false))
goto out;
ret = 0;
*/
BUG_ON(q->info.si_code != SI_TIMER);
q->info.si_overrun++;
+ result = TRACE_SIGNAL_ALREADY_PENDING;
goto out;
}
q->info.si_overrun = 0;
list_add_tail(&q->list, &pending->list);
sigaddset(&pending->signal, sig);
complete_signal(sig, t, group);
+ result = TRACE_SIGNAL_DELIVERED;
out:
+ trace_signal_generate(sig, &q->info, t, group, result);
unlock_task_sighand(t, &flags);
ret:
return ret;
* Let a parent know about the death of a child.
* For a stopped/continued status change, use do_notify_parent_cldstop instead.
*
- * Returns -1 if our parent ignored us and so we've switched to
- * self-reaping, or else @sig.
+ * Returns true if our parent ignored us and so we've switched to
+ * self-reaping.
*/
-int do_notify_parent(struct task_struct *tsk, int sig)
+bool do_notify_parent(struct task_struct *tsk, int sig)
{
struct siginfo info;
unsigned long flags;
struct sighand_struct *psig;
- int ret = sig;
+ bool autoreap = false;
+ cputime_t utime, stime;
BUG_ON(sig == -1);
/* do_notify_parent_cldstop should have been called instead. */
BUG_ON(task_is_stopped_or_traced(tsk));
- BUG_ON(!task_ptrace(tsk) &&
+ BUG_ON(!tsk->ptrace &&
(tsk->group_leader != tsk || !thread_group_empty(tsk)));
+ if (sig != SIGCHLD) {
+ /*
+ * This is only possible if parent == real_parent.
+ * Check if it has changed security domain.
+ */
+ if (tsk->parent_exec_id != tsk->parent->self_exec_id)
+ sig = SIGCHLD;
+ }
+
info.si_signo = sig;
info.si_errno = 0;
/*
- * we are under tasklist_lock here so our parent is tied to
- * us and cannot exit and release its namespace.
+ * We are under tasklist_lock here so our parent is tied to
+ * us and cannot change.
*
- * the only it can is to switch its nsproxy with sys_unshare,
- * bu uncharing pid namespaces is not allowed, so we'll always
- * see relevant namespace
+ * task_active_pid_ns will always return the same pid namespace
+ * until a task passes through release_task.
*
* write_lock() currently calls preempt_disable() which is the
* same as rcu_read_lock(), but according to Oleg, this is not
* correct to rely on this
*/
rcu_read_lock();
- info.si_pid = task_pid_nr_ns(tsk, tsk->parent->nsproxy->pid_ns);
- info.si_uid = __task_cred(tsk)->uid;
+ info.si_pid = task_pid_nr_ns(tsk, task_active_pid_ns(tsk->parent));
+ info.si_uid = from_kuid_munged(task_cred_xxx(tsk->parent, user_ns),
+ task_uid(tsk));
rcu_read_unlock();
- info.si_utime = cputime_to_clock_t(cputime_add(tsk->utime,
- tsk->signal->utime));
- info.si_stime = cputime_to_clock_t(cputime_add(tsk->stime,
- tsk->signal->stime));
+ task_cputime(tsk, &utime, &stime);
+ info.si_utime = cputime_to_clock_t(utime + tsk->signal->utime);
+ info.si_stime = cputime_to_clock_t(stime + tsk->signal->stime);
info.si_status = tsk->exit_code & 0x7f;
if (tsk->exit_code & 0x80)
psig = tsk->parent->sighand;
spin_lock_irqsave(&psig->siglock, flags);
- if (!task_ptrace(tsk) && sig == SIGCHLD &&
+ if (!tsk->ptrace && sig == SIGCHLD &&
(psig->action[SIGCHLD-1].sa.sa_handler == SIG_IGN ||
(psig->action[SIGCHLD-1].sa.sa_flags & SA_NOCLDWAIT))) {
/*
* is implementation-defined: we do (if you don't want
* it, just use SIG_IGN instead).
*/
- ret = tsk->exit_signal = -1;
+ autoreap = true;
if (psig->action[SIGCHLD-1].sa.sa_handler == SIG_IGN)
- sig = -1;
+ sig = 0;
}
- if (valid_signal(sig) && sig > 0)
+ if (valid_signal(sig) && sig)
__group_send_sig_info(sig, &info, tsk->parent);
__wake_up_parent(tsk, tsk->parent);
spin_unlock_irqrestore(&psig->siglock, flags);
- return ret;
+ return autoreap;
}
/**
unsigned long flags;
struct task_struct *parent;
struct sighand_struct *sighand;
+ cputime_t utime, stime;
if (for_ptracer) {
parent = tsk->parent;
* see comment in do_notify_parent() about the following 4 lines
*/
rcu_read_lock();
- info.si_pid = task_pid_nr_ns(tsk, parent->nsproxy->pid_ns);
- info.si_uid = __task_cred(tsk)->uid;
+ info.si_pid = task_pid_nr_ns(tsk, task_active_pid_ns(parent));
+ info.si_uid = from_kuid_munged(task_cred_xxx(parent, user_ns), task_uid(tsk));
rcu_read_unlock();
- info.si_utime = cputime_to_clock_t(tsk->utime);
- info.si_stime = cputime_to_clock_t(tsk->stime);
+ task_cputime(tsk, &utime, &stime);
+ info.si_utime = cputime_to_clock_t(utime);
+ info.si_stime = cputime_to_clock_t(stime);
info.si_code = why;
switch (why) {
static inline int may_ptrace_stop(void)
{
- if (!likely(task_ptrace(current)))
+ if (!likely(current->ptrace))
return 0;
/*
* Are we in the middle of do_coredump?
* If SIGKILL was already sent before the caller unlocked
* ->siglock we must see ->core_state != NULL. Otherwise it
* is safe to enter schedule().
+ *
+ * This is almost outdated, a task with the pending SIGKILL can't
+ * block in TASK_TRACED. But PTRACE_EVENT_EXIT can be reported
+ * after SIGKILL was already dequeued.
*/
if (unlikely(current->mm->core_state) &&
unlikely(current->mm == current->parent->mm))
sigismember(&tsk->signal->shared_pending.signal, SIGKILL);
}
-/*
- * Test whether the target task of the usual cldstop notification - the
- * real_parent of @child - is in the same group as the ptracer.
- */
-static bool real_parent_is_ptracer(struct task_struct *child)
-{
- return same_thread_group(child->parent, child->real_parent);
-}
-
/*
* This must be called with current->sighand->siglock held.
*
}
/*
- * If @why is CLD_STOPPED, we're trapping to participate in a group
- * stop. Do the bookkeeping. Note that if SIGCONT was delievered
- * while siglock was released for the arch hook, PENDING could be
- * clear now. We act as if SIGCONT is received after TASK_TRACED
- * is entered - ignore it.
+ * We're committing to trapping. TRACED should be visible before
+ * TRAPPING is cleared; otherwise, the tracer might fail do_wait().
+ * Also, transition to TRACED and updates to ->jobctl should be
+ * atomic with respect to siglock and should be done after the arch
+ * hook as siglock is released and regrabbed across it.
*/
- if (why == CLD_STOPPED && (current->group_stop & GROUP_STOP_PENDING))
- gstop_done = task_participate_group_stop(current);
+ set_current_state(TASK_TRACED);
current->last_siginfo = info;
current->exit_code = exit_code;
/*
- * TRACED should be visible before TRAPPING is cleared; otherwise,
- * the tracer might fail do_wait().
+ * If @why is CLD_STOPPED, we're trapping to participate in a group
+ * stop. Do the bookkeeping. Note that if SIGCONT was delievered
+ * across siglock relocks since INTERRUPT was scheduled, PENDING
+ * could be clear now. We act as if SIGCONT is received after
+ * TASK_TRACED is entered - ignore it.
*/
- set_current_state(TASK_TRACED);
+ if (why == CLD_STOPPED && (current->jobctl & JOBCTL_STOP_PENDING))
+ gstop_done = task_participate_group_stop(current);
- /*
- * We're committing to trapping. Clearing GROUP_STOP_TRAPPING and
- * transition to TASK_TRACED should be atomic with respect to
- * siglock. This hsould be done after the arch hook as siglock is
- * released and regrabbed across it.
- */
- task_clear_group_stop_trapping(current);
+ /* any trap clears pending STOP trap, STOP trap clears NOTIFY */
+ task_clear_jobctl_pending(current, JOBCTL_TRAP_STOP);
+ if (info && info->si_code >> 8 == PTRACE_EVENT_STOP)
+ task_clear_jobctl_pending(current, JOBCTL_TRAP_NOTIFY);
+
+ /* entering a trap, clear TRAPPING */
+ task_clear_jobctl_trapping(current);
spin_unlock_irq(¤t->sighand->siglock);
read_lock(&tasklist_lock);
* separately unless they're gonna be duplicates.
*/
do_notify_parent_cldstop(current, true, why);
- if (gstop_done && !real_parent_is_ptracer(current))
+ if (gstop_done && ptrace_reparented(current))
do_notify_parent_cldstop(current, false, why);
/*
preempt_disable();
read_unlock(&tasklist_lock);
preempt_enable_no_resched();
- schedule();
+ freezable_schedule();
} else {
/*
* By the time we got the lock, our tracer went away.
*
* If @gstop_done, the ptracer went away between group stop
* completion and here. During detach, it would have set
- * GROUP_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.
+ * 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);
if (clear_code)
current->exit_code = 0;
read_unlock(&tasklist_lock);
}
- /*
- * While in TASK_TRACED, we were considered "frozen enough".
- * Now that we woke up, it's crucial if we're supposed to be
- * frozen that we freeze now before running anything substantial.
- */
- try_to_freeze();
-
/*
* We are back. Now reacquire the siglock before touching
* last_siginfo, so that we are sure to have synchronized with
spin_lock_irq(¤t->sighand->siglock);
current->last_siginfo = NULL;
+ /* LISTENING can be set only during STOP traps, clear it */
+ current->jobctl &= ~JOBCTL_LISTENING;
+
/*
* Queued signals ignored us while we were stopped for tracing.
* So check for any that we should take before resuming user mode.
recalc_sigpending_tsk(current);
}
-void ptrace_notify(int exit_code)
+static void ptrace_do_notify(int signr, int exit_code, int why)
{
siginfo_t info;
- BUG_ON((exit_code & (0x7f | ~0xffff)) != SIGTRAP);
-
memset(&info, 0, sizeof info);
- info.si_signo = SIGTRAP;
+ info.si_signo = signr;
info.si_code = exit_code;
info.si_pid = task_pid_vnr(current);
- info.si_uid = current_uid();
+ info.si_uid = from_kuid_munged(current_user_ns(), current_uid());
/* Let the debugger run. */
+ ptrace_stop(exit_code, why, 1, &info);
+}
+
+void ptrace_notify(int exit_code)
+{
+ BUG_ON((exit_code & (0x7f | ~0xffff)) != SIGTRAP);
+ if (unlikely(current->task_works))
+ task_work_run();
+
spin_lock_irq(¤t->sighand->siglock);
- ptrace_stop(exit_code, CLD_TRAPPED, 1, &info);
+ ptrace_do_notify(SIGTRAP, exit_code, CLD_TRAPPED);
spin_unlock_irq(¤t->sighand->siglock);
}
-/*
- * This performs the stopping for SIGSTOP and other stop signals.
- * We have to stop all threads in the thread group.
- * Returns non-zero if we've actually stopped and released the siglock.
- * Returns zero if we didn't stop and still hold the siglock.
+/**
+ * do_signal_stop - handle group stop for SIGSTOP and other stop signals
+ * @signr: signr causing group stop if initiating
+ *
+ * If %JOBCTL_STOP_PENDING is not set yet, initiate group stop with @signr
+ * and participate in it. If already set, participate in the existing
+ * group stop. If participated in a group stop (and thus slept), %true is
+ * returned with siglock released.
+ *
+ * If ptraced, this function doesn't handle stop itself. Instead,
+ * %JOBCTL_TRAP_STOP is scheduled and %false is returned with siglock
+ * untouched. The caller must ensure that INTERRUPT trap handling takes
+ * places afterwards.
+ *
+ * CONTEXT:
+ * Must be called with @current->sighand->siglock held, which is released
+ * on %true return.
+ *
+ * RETURNS:
+ * %false if group stop is already cancelled or ptrace trap is scheduled.
+ * %true if participated in group stop.
*/
-static int do_signal_stop(int signr)
+static bool do_signal_stop(int signr)
+ __releases(¤t->sighand->siglock)
{
struct signal_struct *sig = current->signal;
- if (!(current->group_stop & GROUP_STOP_PENDING)) {
- unsigned int gstop = GROUP_STOP_PENDING | GROUP_STOP_CONSUME;
+ if (!(current->jobctl & JOBCTL_STOP_PENDING)) {
+ unsigned int gstop = JOBCTL_STOP_PENDING | JOBCTL_STOP_CONSUME;
struct task_struct *t;
- /* signr will be recorded in task->group_stop for retries */
- WARN_ON_ONCE(signr & ~GROUP_STOP_SIGMASK);
+ /* signr will be recorded in task->jobctl for retries */
+ WARN_ON_ONCE(signr & ~JOBCTL_STOP_SIGMASK);
- if (!likely(current->group_stop & GROUP_STOP_DEQUEUED) ||
+ if (!likely(current->jobctl & JOBCTL_STOP_DEQUEUED) ||
unlikely(signal_group_exit(sig)))
- return 0;
+ return false;
/*
* There is no group stop already in progress. We must
* initiate one now.
*/
if (!(sig->flags & SIGNAL_STOP_STOPPED))
sig->group_exit_code = signr;
- else
- WARN_ON_ONCE(!task_ptrace(current));
- current->group_stop &= ~GROUP_STOP_SIGMASK;
- current->group_stop |= signr | gstop;
- sig->group_stop_count = 1;
+ sig->group_stop_count = 0;
+
+ if (task_set_jobctl_pending(current, signr | gstop))
+ sig->group_stop_count++;
+
for (t = next_thread(current); t != current;
t = next_thread(t)) {
- t->group_stop &= ~GROUP_STOP_SIGMASK;
/*
* Setting state to TASK_STOPPED for a group
* stop is always done with the siglock held,
* so this check has no races.
*/
- if (!(t->flags & PF_EXITING) && !task_is_stopped(t)) {
- t->group_stop |= signr | gstop;
+ if (!task_is_stopped(t) &&
+ task_set_jobctl_pending(t, signr | gstop)) {
sig->group_stop_count++;
- signal_wake_up(t, 0);
+ if (likely(!(t->ptrace & PT_SEIZED)))
+ signal_wake_up(t, 0);
+ else
+ ptrace_trap_notify(t);
}
}
}
-retry:
- if (likely(!task_ptrace(current))) {
+
+ if (likely(!current->ptrace)) {
int notify = 0;
/*
}
/* Now we don't run again until woken by SIGCONT or SIGKILL */
- schedule();
-
- spin_lock_irq(¤t->sighand->siglock);
+ freezable_schedule();
+ return true;
} else {
- ptrace_stop(current->group_stop & GROUP_STOP_SIGMASK,
- CLD_STOPPED, 0, NULL);
- current->exit_code = 0;
+ /*
+ * While ptraced, group stop is handled by STOP trap.
+ * Schedule it and let the caller deal with it.
+ */
+ task_set_jobctl_pending(current, JOBCTL_TRAP_STOP);
+ return false;
}
+}
- /*
- * GROUP_STOP_PENDING could be set if another group stop has
- * started since being woken up or ptrace wants us to transit
- * between TASK_STOPPED and TRACED. Retry group stop.
- */
- if (current->group_stop & GROUP_STOP_PENDING) {
- WARN_ON_ONCE(!(current->group_stop & GROUP_STOP_SIGMASK));
- goto retry;
+/**
+ * do_jobctl_trap - take care of ptrace jobctl traps
+ *
+ * When PT_SEIZED, it's used for both group stop and explicit
+ * SEIZE/INTERRUPT traps. Both generate PTRACE_EVENT_STOP trap with
+ * accompanying siginfo. If stopped, lower eight bits of exit_code contain
+ * the stop signal; otherwise, %SIGTRAP.
+ *
+ * When !PT_SEIZED, it's used only for group stop trap with stop signal
+ * number as exit_code and no siginfo.
+ *
+ * CONTEXT:
+ * Must be called with @current->sighand->siglock held, which may be
+ * released and re-acquired before returning with intervening sleep.
+ */
+static void do_jobctl_trap(void)
+{
+ struct signal_struct *signal = current->signal;
+ int signr = current->jobctl & JOBCTL_STOP_SIGMASK;
+
+ if (current->ptrace & PT_SEIZED) {
+ if (!signal->group_stop_count &&
+ !(signal->flags & SIGNAL_STOP_STOPPED))
+ signr = SIGTRAP;
+ WARN_ON_ONCE(!signr);
+ ptrace_do_notify(signr, signr | (PTRACE_EVENT_STOP << 8),
+ CLD_STOPPED);
+ } else {
+ WARN_ON_ONCE(!signr);
+ ptrace_stop(signr, CLD_STOPPED, 0, NULL);
+ current->exit_code = 0;
}
-
- /* PTRACE_ATTACH might have raced with task killing, clear trapping */
- task_clear_group_stop_trapping(current);
-
- spin_unlock_irq(¤t->sighand->siglock);
-
- tracehook_finish_jctl();
-
- return 1;
}
-static int ptrace_signal(int signr, siginfo_t *info,
- struct pt_regs *regs, void *cookie)
+static int ptrace_signal(int signr, siginfo_t *info)
{
- if (!task_ptrace(current))
- return signr;
-
- ptrace_signal_deliver(regs, cookie);
-
- /* Let the debugger run. */
+ ptrace_signal_deliver();
+ /*
+ * We do not check sig_kernel_stop(signr) but set this marker
+ * unconditionally because we do not know whether debugger will
+ * change signr. This flag has no meaning unless we are going
+ * to stop after return from ptrace_stop(). In this case it will
+ * be checked in do_signal_stop(), we should only stop if it was
+ * not cleared by SIGCONT while we were sleeping. See also the
+ * comment in dequeue_signal().
+ */
+ current->jobctl |= JOBCTL_STOP_DEQUEUED;
ptrace_stop(signr, CLD_TRAPPED, 0, info);
/* We're back. Did the debugger cancel the sig? */
info->si_signo = signr;
info->si_errno = 0;
info->si_code = SI_USER;
+ rcu_read_lock();
info->si_pid = task_pid_vnr(current->parent);
- info->si_uid = task_uid(current->parent);
+ info->si_uid = from_kuid_munged(current_user_ns(),
+ task_uid(current->parent));
+ rcu_read_unlock();
}
/* If the (new) signal is now blocked, requeue it. */
struct signal_struct *signal = current->signal;
int signr;
-relock:
+ if (unlikely(current->task_works))
+ task_work_run();
+
+ if (unlikely(uprobe_deny_signal()))
+ return 0;
+
/*
- * We'll jump back here after any time we were stopped in TASK_STOPPED.
- * While in TASK_STOPPED, we were considered "frozen enough".
- * Now that we woke up, it's crucial if we're supposed to be
- * frozen that we freeze now before running anything substantial.
+ * Do this once, we can't return to user-mode if freezing() == T.
+ * do_signal_stop() and ptrace_stop() do freezable_schedule() and
+ * thus do not need another check after return.
*/
try_to_freeze();
+relock:
spin_lock_irq(&sighand->siglock);
/*
* Every stopped thread goes here after wakeup. Check to see if
* the CLD_ si_code into SIGNAL_CLD_MASK bits.
*/
if (unlikely(signal->flags & SIGNAL_CLD_MASK)) {
- struct task_struct *leader;
int why;
if (signal->flags & SIGNAL_CLD_CONTINUED)
* a duplicate.
*/
read_lock(&tasklist_lock);
-
do_notify_parent_cldstop(current, false, why);
- leader = current->group_leader;
- if (task_ptrace(leader) && !real_parent_is_ptracer(leader))
- do_notify_parent_cldstop(leader, true, why);
-
+ if (ptrace_reparented(current->group_leader))
+ do_notify_parent_cldstop(current->group_leader,
+ true, why);
read_unlock(&tasklist_lock);
goto relock;
for (;;) {
struct k_sigaction *ka;
- /*
- * Tracing can induce an artificial signal and choose sigaction.
- * The return value in @signr determines the default action,
- * but @info->si_signo is the signal number we will report.
- */
- signr = tracehook_get_signal(current, regs, info, return_ka);
- if (unlikely(signr < 0))
+
+ if (unlikely(current->jobctl & JOBCTL_STOP_PENDING) &&
+ do_signal_stop(0))
goto relock;
- if (unlikely(signr != 0))
- ka = return_ka;
- else {
- if (unlikely(current->group_stop &
- GROUP_STOP_PENDING) && do_signal_stop(0))
- goto relock;
- signr = dequeue_signal(current, ¤t->blocked,
- info);
+ if (unlikely(current->jobctl & JOBCTL_TRAP_MASK)) {
+ do_jobctl_trap();
+ spin_unlock_irq(&sighand->siglock);
+ goto relock;
+ }
- if (!signr)
- break; /* will return 0 */
+ signr = dequeue_signal(current, ¤t->blocked, info);
- if (signr != SIGKILL) {
- signr = ptrace_signal(signr, info,
- regs, cookie);
- if (!signr)
- continue;
- }
+ if (!signr)
+ break; /* will return 0 */
- ka = &sighand->action[signr-1];
+ if (unlikely(current->ptrace) && signr != SIGKILL) {
+ signr = ptrace_signal(signr, info);
+ if (!signr)
+ continue;
}
+ ka = &sighand->action[signr-1];
+
/* Trace actually delivered signals. */
trace_signal_deliver(signr, info, ka);
if (sig_kernel_coredump(signr)) {
if (print_fatal_signals)
- print_fatal_signal(regs, info->si_signo);
+ print_fatal_signal(info->si_signo);
+ proc_coredump_connector(current);
/*
* If it was able to dump core, this kills all
* other threads in the group and synchronizes with
* first and our do_group_exit call below will use
* that value and ignore the one we pass it.
*/
- do_coredump(info->si_signo, info->si_signo, regs);
+ do_coredump(info);
}
/*
return signr;
}
+/**
+ * signal_delivered -
+ * @sig: number of signal being delivered
+ * @info: siginfo_t of signal being delivered
+ * @ka: sigaction setting that chose the handler
+ * @regs: user register state
+ * @stepping: nonzero if debugger single-step or block-step in use
+ *
+ * This function should be called when a signal has succesfully been
+ * delivered. It updates the blocked signals accordingly (@ka->sa.sa_mask
+ * is always blocked, and the signal itself is blocked unless %SA_NODEFER
+ * is set in @ka->sa.sa_flags. Tracing is notified.
+ */
+void signal_delivered(int sig, siginfo_t *info, struct k_sigaction *ka,
+ struct pt_regs *regs, int stepping)
+{
+ sigset_t blocked;
+
+ /* A signal was successfully delivered, and the
+ saved sigmask was stored on the signal frame,
+ and will be restored by sigreturn. So we can
+ simply clear the restore sigmask flag. */
+ clear_restore_sigmask();
+
+ sigorsets(&blocked, ¤t->blocked, &ka->sa.sa_mask);
+ if (!(ka->sa.sa_flags & SA_NODEFER))
+ sigaddset(&blocked, sig);
+ set_current_blocked(&blocked);
+ tracehook_signal_handler(sig, info, ka, regs, stepping);
+}
+
+void signal_setup_done(int failed, struct ksignal *ksig, int stepping)
+{
+ if (failed)
+ force_sigsegv(ksig->sig, current);
+ else
+ signal_delivered(ksig->sig, &ksig->info, &ksig->ka,
+ signal_pt_regs(), stepping);
+}
+
/*
* It could be that complete_signal() picked us to notify about the
* group-wide signal. Other threads should be notified now to take
int group_stop = 0;
sigset_t unblocked;
+ /*
+ * @tsk is about to have PF_EXITING set - lock out users which
+ * expect stable threadgroup.
+ */
+ threadgroup_change_begin(tsk);
+
if (thread_group_empty(tsk) || signal_group_exit(tsk->signal)) {
tsk->flags |= PF_EXITING;
+ threadgroup_change_end(tsk);
return;
}
* see wants_signal(), do_signal_stop().
*/
tsk->flags |= PF_EXITING;
+
+ threadgroup_change_end(tsk);
+
if (!signal_pending(tsk))
goto out;
signotset(&unblocked);
retarget_shared_pending(tsk, &unblocked);
- if (unlikely(tsk->group_stop & GROUP_STOP_PENDING) &&
+ if (unlikely(tsk->jobctl & JOBCTL_STOP_PENDING) &&
task_participate_group_stop(tsk))
group_stop = CLD_STOPPED;
out:
* It is wrong to change ->blocked directly, this helper should be used
* to ensure the process can't miss a shared signal we are going to block.
*/
-void set_current_blocked(const sigset_t *newset)
+void set_current_blocked(sigset_t *newset)
+{
+ sigdelsetmask(newset, sigmask(SIGKILL) | sigmask(SIGSTOP));
+ __set_current_blocked(newset);
+}
+
+void __set_current_blocked(const sigset_t *newset)
{
struct task_struct *tsk = current;
return -EINVAL;
}
- set_current_blocked(&newset);
+ __set_current_blocked(&newset);
return 0;
}
return 0;
}
-long do_sigpending(void __user *set, unsigned long sigsetsize)
+#ifdef CONFIG_COMPAT
+COMPAT_SYSCALL_DEFINE4(rt_sigprocmask, int, how, compat_sigset_t __user *, nset,
+ compat_sigset_t __user *, oset, compat_size_t, sigsetsize)
{
- long error = -EINVAL;
- sigset_t pending;
+#ifdef __BIG_ENDIAN
+ sigset_t old_set = current->blocked;
+ /* XXX: Don't preclude handling different sized sigset_t's. */
+ if (sigsetsize != sizeof(sigset_t))
+ return -EINVAL;
+
+ if (nset) {
+ compat_sigset_t new32;
+ sigset_t new_set;
+ int error;
+ if (copy_from_user(&new32, nset, sizeof(compat_sigset_t)))
+ return -EFAULT;
+
+ sigset_from_compat(&new_set, &new32);
+ sigdelsetmask(&new_set, sigmask(SIGKILL)|sigmask(SIGSTOP));
+
+ error = sigprocmask(how, &new_set, NULL);
+ if (error)
+ return error;
+ }
+ if (oset) {
+ compat_sigset_t old32;
+ sigset_to_compat(&old32, &old_set);
+ if (copy_to_user(oset, &old32, sizeof(compat_sigset_t)))
+ return -EFAULT;
+ }
+ return 0;
+#else
+ return sys_rt_sigprocmask(how, (sigset_t __user *)nset,
+ (sigset_t __user *)oset, sigsetsize);
+#endif
+}
+#endif
+
+static int do_sigpending(void *set, unsigned long sigsetsize)
+{
if (sigsetsize > sizeof(sigset_t))
- goto out;
+ return -EINVAL;
spin_lock_irq(¤t->sighand->siglock);
- sigorsets(&pending, ¤t->pending.signal,
+ sigorsets(set, ¤t->pending.signal,
¤t->signal->shared_pending.signal);
spin_unlock_irq(¤t->sighand->siglock);
/* Outside the lock because only this thread touches it. */
- sigandsets(&pending, ¤t->blocked, &pending);
-
- error = -EFAULT;
- if (!copy_to_user(set, &pending, sigsetsize))
- error = 0;
-
-out:
- return error;
+ sigandsets(set, ¤t->blocked, set);
+ return 0;
}
/**
* sys_rt_sigpending - examine a pending signal that has been raised
* while blocked
- * @set: stores pending signals
+ * @uset: stores pending signals
* @sigsetsize: size of sigset_t type or larger
*/
-SYSCALL_DEFINE2(rt_sigpending, sigset_t __user *, set, size_t, sigsetsize)
+SYSCALL_DEFINE2(rt_sigpending, sigset_t __user *, uset, size_t, sigsetsize)
+{
+ sigset_t set;
+ int err = do_sigpending(&set, sigsetsize);
+ if (!err && copy_to_user(uset, &set, sigsetsize))
+ err = -EFAULT;
+ return err;
+}
+
+#ifdef CONFIG_COMPAT
+COMPAT_SYSCALL_DEFINE2(rt_sigpending, compat_sigset_t __user *, uset,
+ compat_size_t, sigsetsize)
{
- return do_sigpending(set, sigsetsize);
+#ifdef __BIG_ENDIAN
+ sigset_t set;
+ int err = do_sigpending(&set, sigsetsize);
+ if (!err) {
+ compat_sigset_t set32;
+ sigset_to_compat(&set32, &set);
+ /* we can get here only if sigsetsize <= sizeof(set) */
+ if (copy_to_user(uset, &set32, sigsetsize))
+ err = -EFAULT;
+ }
+ return err;
+#else
+ return sys_rt_sigpending((sigset_t __user *)uset, sigsetsize);
+#endif
}
+#endif
#ifndef HAVE_ARCH_COPY_SIGINFO_TO_USER
err |= __put_user(from->si_uid, &to->si_uid);
err |= __put_user(from->si_ptr, &to->si_ptr);
break;
+#ifdef __ARCH_SIGSYS
+ case __SI_SYS:
+ err |= __put_user(from->si_call_addr, &to->si_call_addr);
+ err |= __put_user(from->si_syscall, &to->si_syscall);
+ err |= __put_user(from->si_arch, &to->si_arch);
+ break;
+#endif
default: /* this is just in case for now ... */
err |= __put_user(from->si_pid, &to->si_pid);
err |= __put_user(from->si_uid, &to->si_uid);
info.si_errno = 0;
info.si_code = SI_USER;
info.si_pid = task_tgid_vnr(current);
- info.si_uid = current_uid();
+ info.si_uid = from_kuid_munged(current_user_ns(), current_uid());
return kill_something_info(sig, &info, pid);
}
static int do_tkill(pid_t tgid, pid_t pid, int sig)
{
- struct siginfo info;
+ struct siginfo info = {};
info.si_signo = sig;
info.si_errno = 0;
info.si_code = SI_TKILL;
info.si_pid = task_tgid_vnr(current);
- info.si_uid = current_uid();
+ info.si_uid = from_kuid_munged(current_user_ns(), current_uid());
return do_send_specific(tgid, pid, sig, &info);
}
return do_tkill(0, pid, sig);
}
+static int do_rt_sigqueueinfo(pid_t pid, int sig, siginfo_t *info)
+{
+ /* Not even root can pretend to send signals from the kernel.
+ * Nor can they impersonate a kill()/tgkill(), which adds source info.
+ */
+ if ((info->si_code >= 0 || info->si_code == SI_TKILL) &&
+ (task_pid_vnr(current) != pid)) {
+ /* We used to allow any < 0 si_code */
+ WARN_ON_ONCE(info->si_code < 0);
+ return -EPERM;
+ }
+ info->si_signo = sig;
+
+ /* POSIX.1b doesn't mention process groups. */
+ return kill_proc_info(sig, info, pid);
+}
+
/**
* sys_rt_sigqueueinfo - send signal information to a signal
* @pid: the PID of the thread
siginfo_t __user *, uinfo)
{
siginfo_t info;
-
if (copy_from_user(&info, uinfo, sizeof(siginfo_t)))
return -EFAULT;
+ return do_rt_sigqueueinfo(pid, sig, &info);
+}
- /* Not even root can pretend to send signals from the kernel.
- * Nor can they impersonate a kill()/tgkill(), which adds source info.
- */
- if (info.si_code >= 0 || info.si_code == SI_TKILL) {
- /* We used to allow any < 0 si_code */
- WARN_ON_ONCE(info.si_code < 0);
- return -EPERM;
- }
- info.si_signo = sig;
-
- /* POSIX.1b doesn't mention process groups. */
- return kill_proc_info(sig, &info, pid);
+#ifdef CONFIG_COMPAT
+COMPAT_SYSCALL_DEFINE3(rt_sigqueueinfo,
+ compat_pid_t, pid,
+ int, sig,
+ struct compat_siginfo __user *, uinfo)
+{
+ siginfo_t info;
+ int ret = copy_siginfo_from_user32(&info, uinfo);
+ if (unlikely(ret))
+ return ret;
+ return do_rt_sigqueueinfo(pid, sig, &info);
}
+#endif
-long do_rt_tgsigqueueinfo(pid_t tgid, pid_t pid, int sig, siginfo_t *info)
+static int do_rt_tgsigqueueinfo(pid_t tgid, pid_t pid, int sig, siginfo_t *info)
{
/* This is only valid for single tasks */
if (pid <= 0 || tgid <= 0)
/* Not even root can pretend to send signals from the kernel.
* Nor can they impersonate a kill()/tgkill(), which adds source info.
*/
- if (info->si_code >= 0 || info->si_code == SI_TKILL) {
+ if (((info->si_code >= 0 || info->si_code == SI_TKILL)) &&
+ (task_pid_vnr(current) != pid)) {
/* We used to allow any < 0 si_code */
WARN_ON_ONCE(info->si_code < 0);
return -EPERM;
return do_rt_tgsigqueueinfo(tgid, pid, sig, &info);
}
+#ifdef CONFIG_COMPAT
+COMPAT_SYSCALL_DEFINE4(rt_tgsigqueueinfo,
+ compat_pid_t, tgid,
+ compat_pid_t, pid,
+ int, sig,
+ struct compat_siginfo __user *, uinfo)
+{
+ siginfo_t info;
+
+ if (copy_siginfo_from_user32(&info, uinfo))
+ return -EFAULT;
+ return do_rt_tgsigqueueinfo(tgid, pid, sig, &info);
+}
+#endif
+
int do_sigaction(int sig, struct k_sigaction *act, struct k_sigaction *oact)
{
struct task_struct *t = current;
return 0;
}
-int
+static int
do_sigaltstack (const stack_t __user *uss, stack_t __user *uoss, unsigned long sp)
{
stack_t oss;
out:
return error;
}
+SYSCALL_DEFINE2(sigaltstack,const stack_t __user *,uss, stack_t __user *,uoss)
+{
+ return do_sigaltstack(uss, uoss, current_user_stack_pointer());
+}
+
+int restore_altstack(const stack_t __user *uss)
+{
+ int err = do_sigaltstack(uss, NULL, current_user_stack_pointer());
+ /* squash all but EFAULT for now */
+ return err == -EFAULT ? err : 0;
+}
+
+int __save_altstack(stack_t __user *uss, unsigned long sp)
+{
+ struct task_struct *t = current;
+ return __put_user((void __user *)t->sas_ss_sp, &uss->ss_sp) |
+ __put_user(sas_ss_flags(sp), &uss->ss_flags) |
+ __put_user(t->sas_ss_size, &uss->ss_size);
+}
+
+#ifdef CONFIG_COMPAT
+COMPAT_SYSCALL_DEFINE2(sigaltstack,
+ const compat_stack_t __user *, uss_ptr,
+ compat_stack_t __user *, uoss_ptr)
+{
+ stack_t uss, uoss;
+ int ret;
+ mm_segment_t seg;
+
+ if (uss_ptr) {
+ compat_stack_t uss32;
+
+ memset(&uss, 0, sizeof(stack_t));
+ if (copy_from_user(&uss32, uss_ptr, sizeof(compat_stack_t)))
+ return -EFAULT;
+ uss.ss_sp = compat_ptr(uss32.ss_sp);
+ uss.ss_flags = uss32.ss_flags;
+ uss.ss_size = uss32.ss_size;
+ }
+ seg = get_fs();
+ set_fs(KERNEL_DS);
+ ret = do_sigaltstack((stack_t __force __user *) (uss_ptr ? &uss : NULL),
+ (stack_t __force __user *) &uoss,
+ compat_user_stack_pointer());
+ set_fs(seg);
+ if (ret >= 0 && uoss_ptr) {
+ if (!access_ok(VERIFY_WRITE, uoss_ptr, sizeof(compat_stack_t)) ||
+ __put_user(ptr_to_compat(uoss.ss_sp), &uoss_ptr->ss_sp) ||
+ __put_user(uoss.ss_flags, &uoss_ptr->ss_flags) ||
+ __put_user(uoss.ss_size, &uoss_ptr->ss_size))
+ ret = -EFAULT;
+ }
+ return ret;
+}
+
+int compat_restore_altstack(const compat_stack_t __user *uss)
+{
+ int err = compat_sys_sigaltstack(uss, NULL);
+ /* squash all but -EFAULT for now */
+ return err == -EFAULT ? err : 0;
+}
+
+int __compat_save_altstack(compat_stack_t __user *uss, unsigned long sp)
+{
+ struct task_struct *t = current;
+ return __put_user(ptr_to_compat((void __user *)t->sas_ss_sp), &uss->ss_sp) |
+ __put_user(sas_ss_flags(sp), &uss->ss_flags) |
+ __put_user(t->sas_ss_size, &uss->ss_size);
+}
+#endif
#ifdef __ARCH_WANT_SYS_SIGPENDING
*/
SYSCALL_DEFINE1(sigpending, old_sigset_t __user *, set)
{
- return do_sigpending(set, sizeof(*set));
+ return sys_rt_sigpending((sigset_t __user *)set, sizeof(old_sigset_t));
}
#endif
if (nset) {
if (copy_from_user(&new_set, nset, sizeof(*nset)))
return -EFAULT;
- new_set &= ~(sigmask(SIGKILL) | sigmask(SIGSTOP));
new_blocked = current->blocked;
}
#endif /* __ARCH_WANT_SYS_SIGPROCMASK */
-#ifdef __ARCH_WANT_SYS_RT_SIGACTION
+#ifndef CONFIG_ODD_RT_SIGACTION
/**
* sys_rt_sigaction - alter an action taken by a process
* @sig: signal to be sent
out:
return ret;
}
-#endif /* __ARCH_WANT_SYS_RT_SIGACTION */
+#ifdef CONFIG_COMPAT
+COMPAT_SYSCALL_DEFINE4(rt_sigaction, int, sig,
+ const struct compat_sigaction __user *, act,
+ struct compat_sigaction __user *, oact,
+ compat_size_t, sigsetsize)
+{
+ struct k_sigaction new_ka, old_ka;
+ compat_sigset_t mask;
+#ifdef __ARCH_HAS_SA_RESTORER
+ compat_uptr_t restorer;
+#endif
+ int ret;
+
+ /* XXX: Don't preclude handling different sized sigset_t's. */
+ if (sigsetsize != sizeof(compat_sigset_t))
+ return -EINVAL;
+
+ if (act) {
+ compat_uptr_t handler;
+ ret = get_user(handler, &act->sa_handler);
+ new_ka.sa.sa_handler = compat_ptr(handler);
+#ifdef __ARCH_HAS_SA_RESTORER
+ ret |= get_user(restorer, &act->sa_restorer);
+ new_ka.sa.sa_restorer = compat_ptr(restorer);
+#endif
+ ret |= copy_from_user(&mask, &act->sa_mask, sizeof(mask));
+ ret |= __get_user(new_ka.sa.sa_flags, &act->sa_flags);
+ if (ret)
+ return -EFAULT;
+ sigset_from_compat(&new_ka.sa.sa_mask, &mask);
+ }
+
+ ret = do_sigaction(sig, act ? &new_ka : NULL, oact ? &old_ka : NULL);
+ if (!ret && oact) {
+ sigset_to_compat(&mask, &old_ka.sa.sa_mask);
+ ret = put_user(ptr_to_compat(old_ka.sa.sa_handler),
+ &oact->sa_handler);
+ ret |= copy_to_user(&oact->sa_mask, &mask, sizeof(mask));
+ ret |= __put_user(old_ka.sa.sa_flags, &oact->sa_flags);
+#ifdef __ARCH_HAS_SA_RESTORER
+ ret |= put_user(ptr_to_compat(old_ka.sa.sa_restorer),
+ &oact->sa_restorer);
+#endif
+ }
+ return ret;
+}
+#endif
+#endif /* !CONFIG_ODD_RT_SIGACTION */
+
+#ifdef CONFIG_OLD_SIGACTION
+SYSCALL_DEFINE3(sigaction, int, sig,
+ const struct old_sigaction __user *, act,
+ struct old_sigaction __user *, oact)
+{
+ struct k_sigaction new_ka, old_ka;
+ int ret;
+
+ if (act) {
+ old_sigset_t mask;
+ if (!access_ok(VERIFY_READ, act, sizeof(*act)) ||
+ __get_user(new_ka.sa.sa_handler, &act->sa_handler) ||
+ __get_user(new_ka.sa.sa_restorer, &act->sa_restorer) ||
+ __get_user(new_ka.sa.sa_flags, &act->sa_flags) ||
+ __get_user(mask, &act->sa_mask))
+ return -EFAULT;
+#ifdef __ARCH_HAS_KA_RESTORER
+ new_ka.ka_restorer = NULL;
+#endif
+ siginitset(&new_ka.sa.sa_mask, mask);
+ }
+
+ ret = do_sigaction(sig, act ? &new_ka : NULL, oact ? &old_ka : NULL);
+
+ if (!ret && oact) {
+ if (!access_ok(VERIFY_WRITE, oact, sizeof(*oact)) ||
+ __put_user(old_ka.sa.sa_handler, &oact->sa_handler) ||
+ __put_user(old_ka.sa.sa_restorer, &oact->sa_restorer) ||
+ __put_user(old_ka.sa.sa_flags, &oact->sa_flags) ||
+ __put_user(old_ka.sa.sa_mask.sig[0], &oact->sa_mask))
+ return -EFAULT;
+ }
+
+ return ret;
+}
+#endif
+#ifdef CONFIG_COMPAT_OLD_SIGACTION
+COMPAT_SYSCALL_DEFINE3(sigaction, int, sig,
+ const struct compat_old_sigaction __user *, act,
+ struct compat_old_sigaction __user *, oact)
+{
+ struct k_sigaction new_ka, old_ka;
+ int ret;
+ compat_old_sigset_t mask;
+ compat_uptr_t handler, restorer;
+
+ if (act) {
+ if (!access_ok(VERIFY_READ, act, sizeof(*act)) ||
+ __get_user(handler, &act->sa_handler) ||
+ __get_user(restorer, &act->sa_restorer) ||
+ __get_user(new_ka.sa.sa_flags, &act->sa_flags) ||
+ __get_user(mask, &act->sa_mask))
+ return -EFAULT;
+
+#ifdef __ARCH_HAS_KA_RESTORER
+ new_ka.ka_restorer = NULL;
+#endif
+ new_ka.sa.sa_handler = compat_ptr(handler);
+ new_ka.sa.sa_restorer = compat_ptr(restorer);
+ siginitset(&new_ka.sa.sa_mask, mask);
+ }
+
+ ret = do_sigaction(sig, act ? &new_ka : NULL, oact ? &old_ka : NULL);
+
+ if (!ret && oact) {
+ if (!access_ok(VERIFY_WRITE, oact, sizeof(*oact)) ||
+ __put_user(ptr_to_compat(old_ka.sa.sa_handler),
+ &oact->sa_handler) ||
+ __put_user(ptr_to_compat(old_ka.sa.sa_restorer),
+ &oact->sa_restorer) ||
+ __put_user(old_ka.sa.sa_flags, &oact->sa_flags) ||
+ __put_user(old_ka.sa.sa_mask.sig[0], &oact->sa_mask))
+ return -EFAULT;
+ }
+ return ret;
+}
+#endif
#ifdef __ARCH_WANT_SYS_SGETMASK
SYSCALL_DEFINE1(ssetmask, int, newmask)
{
- int old;
-
- spin_lock_irq(¤t->sighand->siglock);
- old = current->blocked.sig[0];
+ int old = current->blocked.sig[0];
+ sigset_t newset;
- siginitset(¤t->blocked, newmask & ~(sigmask(SIGKILL)|
- sigmask(SIGSTOP)));
- recalc_sigpending();
- spin_unlock_irq(¤t->sighand->siglock);
+ siginitset(&newset, newmask);
+ set_current_blocked(&newset);
return old;
}
#endif
-#ifdef __ARCH_WANT_SYS_RT_SIGSUSPEND
+int sigsuspend(sigset_t *set)
+{
+ current->saved_sigmask = current->blocked;
+ set_current_blocked(set);
+
+ current->state = TASK_INTERRUPTIBLE;
+ schedule();
+ set_restore_sigmask();
+ return -ERESTARTNOHAND;
+}
+
/**
* sys_rt_sigsuspend - replace the signal mask for a value with the
* @unewset value until a signal is received
if (copy_from_user(&newset, unewset, sizeof(newset)))
return -EFAULT;
- sigdelsetmask(&newset, sigmask(SIGKILL)|sigmask(SIGSTOP));
+ return sigsuspend(&newset);
+}
+
+#ifdef CONFIG_COMPAT
+COMPAT_SYSCALL_DEFINE2(rt_sigsuspend, compat_sigset_t __user *, unewset, compat_size_t, sigsetsize)
+{
+#ifdef __BIG_ENDIAN
+ sigset_t newset;
+ compat_sigset_t newset32;
- spin_lock_irq(¤t->sighand->siglock);
- current->saved_sigmask = current->blocked;
- current->blocked = newset;
- recalc_sigpending();
- spin_unlock_irq(¤t->sighand->siglock);
+ /* XXX: Don't preclude handling different sized sigset_t's. */
+ if (sigsetsize != sizeof(sigset_t))
+ return -EINVAL;
- current->state = TASK_INTERRUPTIBLE;
- schedule();
- set_restore_sigmask();
- return -ERESTARTNOHAND;
+ if (copy_from_user(&newset32, unewset, sizeof(compat_sigset_t)))
+ return -EFAULT;
+ sigset_from_compat(&newset, &newset32);
+ return sigsuspend(&newset);
+#else
+ /* on little-endian bitmaps don't care about granularity */
+ return sys_rt_sigsuspend((sigset_t __user *)unewset, sigsetsize);
+#endif
}
-#endif /* __ARCH_WANT_SYS_RT_SIGSUSPEND */
+#endif
+
+#ifdef CONFIG_OLD_SIGSUSPEND
+SYSCALL_DEFINE1(sigsuspend, old_sigset_t, mask)
+{
+ sigset_t blocked;
+ siginitset(&blocked, mask);
+ return sigsuspend(&blocked);
+}
+#endif
+#ifdef CONFIG_OLD_SIGSUSPEND3
+SYSCALL_DEFINE3(sigsuspend, int, unused1, int, unused2, old_sigset_t, mask)
+{
+ sigset_t blocked;
+ siginitset(&blocked, mask);
+ return sigsuspend(&blocked);
+}
+#endif
__attribute__((weak)) const char *arch_vma_name(struct vm_area_struct *vma)
{