* formats.
*/
-#include <linux/config.h>
#include <linux/slab.h>
#include <linux/file.h>
#include <linux/mman.h>
#include <linux/security.h>
#include <linux/syscalls.h>
#include <linux/rmap.h>
-#include <linux/acct.h>
+#include <linux/tsacct_kern.h>
#include <linux/cn_proc.h>
+#include <linux/audit.h>
#include <asm/uaccess.h>
#include <asm/mmu_context.h>
#endif
int core_uses_pid;
-char core_pattern[65] = "core";
+char core_pattern[128] = "core";
int suid_dumpable = 0;
EXPORT_SYMBOL(suid_dumpable);
struct nameidata nd;
int error;
- error = __user_path_lookup_open(library, LOOKUP_FOLLOW, &nd, FMODE_READ);
+ error = __user_path_lookup_open(library, LOOKUP_FOLLOW, &nd, FMODE_READ|FMODE_EXEC);
if (error)
goto out;
int err;
struct file *file;
- err = path_lookup_open(AT_FDCWD, name, LOOKUP_FOLLOW, &nd, FMODE_READ);
+ err = path_lookup_open(AT_FDCWD, name, LOOKUP_FOLLOW, &nd, FMODE_READ|FMODE_EXEC);
file = ERR_PTR(err);
if (!err) {
if (!(nd.mnt->mnt_flags & MNT_NOEXEC) &&
S_ISREG(inode->i_mode)) {
int err = vfs_permission(&nd, MAY_EXEC);
- if (!err && !(inode->i_mode & 0111))
- err = -EACCES;
file = ERR_PTR(err);
if (!err) {
file = nameidata_to_filp(&nd, O_RDONLY);
arch_pick_mmap_layout(mm);
if (old_mm) {
up_read(&old_mm->mmap_sem);
- if (active_mm != old_mm) BUG();
+ BUG_ON(active_mm != old_mm);
mmput(old_mm);
return 0;
}
if (!newsighand)
return -ENOMEM;
- if (thread_group_empty(current))
+ if (thread_group_empty(tsk))
goto no_thread_group;
/*
kmem_cache_free(sighand_cachep, newsighand);
return -EAGAIN;
}
- zap_other_threads(current);
+
+ /*
+ * child_reaper ignores SIGKILL, change it now.
+ * Reparenting needs write_lock on tasklist_lock,
+ * so it is safe to do it under read_lock.
+ */
+ if (unlikely(tsk->group_leader == child_reaper))
+ child_reaper = tsk;
+
+ zap_other_threads(tsk);
read_unlock(&tasklist_lock);
/*
* Account for the thread group leader hanging around:
*/
count = 1;
- if (!thread_group_leader(current)) {
+ if (!thread_group_leader(tsk)) {
count = 2;
/*
* The SIGALRM timer survives the exec, but needs to point
* synchronize with any firing (by calling del_timer_sync)
* before we can safely let the old group leader die.
*/
- sig->real_timer.data = current;
+ sig->tsk = tsk;
spin_unlock_irq(lock);
if (hrtimer_cancel(&sig->real_timer))
hrtimer_restart(&sig->real_timer);
spin_lock_irq(lock);
}
while (atomic_read(&sig->count) > count) {
- sig->group_exit_task = current;
+ sig->group_exit_task = tsk;
sig->notify_count = count;
__set_current_state(TASK_UNINTERRUPTIBLE);
spin_unlock_irq(lock);
* do is to wait for the thread group leader to become inactive,
* and to assume its PID:
*/
- if (!thread_group_leader(current)) {
- struct task_struct *parent;
- struct dentry *proc_dentry1, *proc_dentry2;
- unsigned long ptrace;
-
+ if (!thread_group_leader(tsk)) {
/*
* Wait for the thread group leader to be a zombie.
* It should already be zombie at this point, most
* of the time.
*/
- leader = current->group_leader;
+ leader = tsk->group_leader;
while (leader->exit_state != EXIT_ZOMBIE)
yield();
- spin_lock(&leader->proc_lock);
- spin_lock(¤t->proc_lock);
- proc_dentry1 = proc_pid_unhash(current);
- proc_dentry2 = proc_pid_unhash(leader);
+ /*
+ * The only record we have of the real-time age of a
+ * process, regardless of execs it's done, is start_time.
+ * All the past CPU time is accumulated in signal_struct
+ * from sister threads now dead. But in this non-leader
+ * exec, nothing survives from the original leader thread,
+ * whose birth marks the true age of this process now.
+ * When we take on its identity by switching to its PID, we
+ * also take its birthdate (always earlier than our own).
+ */
+ tsk->start_time = leader->start_time;
+
write_lock_irq(&tasklist_lock);
- BUG_ON(leader->tgid != current->tgid);
- BUG_ON(current->pid == current->tgid);
+ BUG_ON(leader->tgid != tsk->tgid);
+ BUG_ON(tsk->pid == tsk->tgid);
/*
* An exec() starts a new thread group with the
* TGID of the previous thread group. Rehash the
* two threads with a switched PID, and release
* the former thread group leader:
*/
- ptrace = leader->ptrace;
- parent = leader->parent;
- if (unlikely(ptrace) && unlikely(parent == current)) {
- /*
- * Joker was ptracing his own group leader,
- * and now he wants to be his own parent!
- * We can't have that.
- */
- ptrace = 0;
- }
- ptrace_unlink(current);
- ptrace_unlink(leader);
- remove_parent(current);
- remove_parent(leader);
-
- switch_exec_pids(leader, current);
-
- current->parent = current->real_parent = leader->real_parent;
- leader->parent = leader->real_parent = child_reaper;
- current->group_leader = current;
- leader->group_leader = leader;
+ /* Become a process group leader with the old leader's pid.
+ * The old leader becomes a thread of the this thread group.
+ * Note: The old leader also uses this pid until release_task
+ * is called. Odd but simple and correct.
+ */
+ detach_pid(tsk, PIDTYPE_PID);
+ tsk->pid = leader->pid;
+ attach_pid(tsk, PIDTYPE_PID, tsk->pid);
+ transfer_pid(leader, tsk, PIDTYPE_PGID);
+ transfer_pid(leader, tsk, PIDTYPE_SID);
+ list_replace_rcu(&leader->tasks, &tsk->tasks);
- add_parent(current, current->parent);
- add_parent(leader, leader->parent);
- if (ptrace) {
- current->ptrace = ptrace;
- __ptrace_link(current, parent);
- }
+ tsk->group_leader = tsk;
+ leader->group_leader = tsk;
- list_del(¤t->tasks);
- list_add_tail(¤t->tasks, &init_task.tasks);
- current->exit_signal = SIGCHLD;
+ tsk->exit_signal = SIGCHLD;
BUG_ON(leader->exit_state != EXIT_ZOMBIE);
leader->exit_state = EXIT_DEAD;
write_unlock_irq(&tasklist_lock);
- spin_unlock(&leader->proc_lock);
- spin_unlock(¤t->proc_lock);
- proc_pid_flush(proc_dentry1);
- proc_pid_flush(proc_dentry2);
}
/*
/*
* Move our state over to newsighand and switch it in.
*/
- spin_lock_init(&newsighand->siglock);
atomic_set(&newsighand->count, 1);
memcpy(newsighand->action, oldsighand->action,
sizeof(newsighand->action));
write_lock_irq(&tasklist_lock);
spin_lock(&oldsighand->siglock);
- spin_lock(&newsighand->siglock);
+ spin_lock_nested(&newsighand->siglock, SINGLE_DEPTH_NESTING);
- rcu_assign_pointer(current->sighand, newsighand);
+ rcu_assign_pointer(tsk->sighand, newsighand);
recalc_sigpending();
spin_unlock(&newsighand->siglock);
write_unlock_irq(&tasklist_lock);
if (atomic_dec_and_test(&oldsighand->count))
- sighand_free(oldsighand);
+ kmem_cache_free(sighand_cachep, oldsighand);
}
- BUG_ON(!thread_group_leader(current));
+ BUG_ON(!thread_group_leader(tsk));
return 0;
}
bprm->mm = NULL; /* We're using it now */
/* This is the point of no return */
- steal_locks(files);
put_files_struct(files);
current->sas_ss_sp = current->sas_ss_size = 0;
current->flags &= ~PF_RANDOMIZE;
flush_thread();
+ /* Set the new mm task size. We have to do that late because it may
+ * depend on TIF_32BIT which is only updated in flush_thread() on
+ * some architectures like powerpc
+ */
+ current->mm->task_size = TASK_SIZE;
+
if (bprm->e_uid != current->euid || bprm->e_gid != current->egid ||
file_permission(bprm->file, MAY_READ) ||
(bprm->interp_flags & BINPRM_FLAGS_ENFORCE_NONDUMP)) {
return 0;
mmap_failed:
- put_files_struct(current->files);
- current->files = files;
+ reset_files_struct(current, files);
out:
return retval;
}
int retval;
mode = inode->i_mode;
- /*
- * Check execute perms again - if the caller has CAP_DAC_OVERRIDE,
- * generic_permission lets a non-executable through
- */
- if (!(mode & 0111)) /* with at least _one_ execute bit set */
- return -EACCES;
if (bprm->file->f_op == NULL)
return -EACCES;
/* kernel module loader fixup */
/* so we don't try to load run modprobe in kernel space. */
set_fs(USER_DS);
+
+ retval = audit_bprm(bprm);
+ if (retval)
+ return retval;
+
retval = -ENOENT;
for (try=0; try<2; try++) {
read_lock(&binfmt_lock);
int i;
retval = -ENOMEM;
- bprm = kmalloc(sizeof(*bprm), GFP_KERNEL);
+ bprm = kzalloc(sizeof(*bprm), GFP_KERNEL);
if (!bprm)
goto out_ret;
- memset(bprm, 0, sizeof(*bprm));
file = open_exec(filename);
retval = PTR_ERR(file);
case 'h':
down_read(&uts_sem);
rc = snprintf(out_ptr, out_end - out_ptr,
- "%s", system_utsname.nodename);
+ "%s", utsname()->nodename);
up_read(&uts_sem);
if (rc > out_end - out_ptr)
goto out;
*out_ptr = 0;
}
-static void zap_threads (struct mm_struct *mm)
+static void zap_process(struct task_struct *start)
{
- struct task_struct *g, *p;
- struct task_struct *tsk = current;
- struct completion *vfork_done = tsk->vfork_done;
- int traced = 0;
+ struct task_struct *t;
- /*
- * Make sure nobody is waiting for us to release the VM,
- * otherwise we can deadlock when we wait on each other
- */
- if (vfork_done) {
- tsk->vfork_done = NULL;
- complete(vfork_done);
- }
+ start->signal->flags = SIGNAL_GROUP_EXIT;
+ start->signal->group_stop_count = 0;
- read_lock(&tasklist_lock);
- do_each_thread(g,p)
- if (mm == p->mm && p != tsk) {
- force_sig_specific(SIGKILL, p);
- mm->core_waiters++;
- if (unlikely(p->ptrace) &&
- unlikely(p->parent->mm == mm))
- traced = 1;
+ t = start;
+ do {
+ if (t != current && t->mm) {
+ t->mm->core_waiters++;
+ sigaddset(&t->pending.signal, SIGKILL);
+ signal_wake_up(t, 1);
}
- while_each_thread(g,p);
+ } while ((t = next_thread(t)) != start);
+}
- read_unlock(&tasklist_lock);
+static inline int zap_threads(struct task_struct *tsk, struct mm_struct *mm,
+ int exit_code)
+{
+ struct task_struct *g, *p;
+ unsigned long flags;
+ int err = -EAGAIN;
+
+ spin_lock_irq(&tsk->sighand->siglock);
+ if (!(tsk->signal->flags & SIGNAL_GROUP_EXIT)) {
+ tsk->signal->group_exit_code = exit_code;
+ zap_process(tsk);
+ err = 0;
+ }
+ spin_unlock_irq(&tsk->sighand->siglock);
+ if (err)
+ return err;
- if (unlikely(traced)) {
- /*
- * We are zapping a thread and the thread it ptraces.
- * If the tracee went into a ptrace stop for exit tracing,
- * we could deadlock since the tracer is waiting for this
- * coredump to finish. Detach them so they can both die.
- */
- write_lock_irq(&tasklist_lock);
- do_each_thread(g,p) {
- if (mm == p->mm && p != tsk &&
- p->ptrace && p->parent->mm == mm) {
- __ptrace_unlink(p);
+ if (atomic_read(&mm->mm_users) == mm->core_waiters + 1)
+ goto done;
+
+ rcu_read_lock();
+ for_each_process(g) {
+ if (g == tsk->group_leader)
+ continue;
+
+ p = g;
+ do {
+ if (p->mm) {
+ if (p->mm == mm) {
+ /*
+ * p->sighand can't disappear, but
+ * may be changed by de_thread()
+ */
+ lock_task_sighand(p, &flags);
+ zap_process(p);
+ unlock_task_sighand(p, &flags);
+ }
+ break;
}
- } while_each_thread(g,p);
- write_unlock_irq(&tasklist_lock);
+ } while ((p = next_thread(p)) != g);
}
+ rcu_read_unlock();
+done:
+ return mm->core_waiters;
}
-static void coredump_wait(struct mm_struct *mm)
+static int coredump_wait(int exit_code)
{
- DECLARE_COMPLETION(startup_done);
+ struct task_struct *tsk = current;
+ struct mm_struct *mm = tsk->mm;
+ struct completion startup_done;
+ struct completion *vfork_done;
int core_waiters;
+ init_completion(&mm->core_done);
+ init_completion(&startup_done);
mm->core_startup_done = &startup_done;
- zap_threads(mm);
- core_waiters = mm->core_waiters;
+ core_waiters = zap_threads(tsk, mm, exit_code);
up_write(&mm->mmap_sem);
+ if (unlikely(core_waiters < 0))
+ goto fail;
+
+ /*
+ * Make sure nobody is waiting for us to release the VM,
+ * otherwise we can deadlock when we wait on each other
+ */
+ vfork_done = tsk->vfork_done;
+ if (vfork_done) {
+ tsk->vfork_done = NULL;
+ complete(vfork_done);
+ }
+
if (core_waiters)
wait_for_completion(&startup_done);
+fail:
BUG_ON(mm->core_waiters);
+ return core_waiters;
}
int do_coredump(long signr, int exit_code, struct pt_regs * regs)
int retval = 0;
int fsuid = current->fsuid;
int flag = 0;
+ int ispipe = 0;
binfmt = current->binfmt;
if (!binfmt || !binfmt->core_dump)
}
mm->dumpable = 0;
- retval = -EAGAIN;
- spin_lock_irq(¤t->sighand->siglock);
- if (!(current->signal->flags & SIGNAL_GROUP_EXIT)) {
- current->signal->flags = SIGNAL_GROUP_EXIT;
- current->signal->group_exit_code = exit_code;
- current->signal->group_stop_count = 0;
- retval = 0;
- }
- spin_unlock_irq(¤t->sighand->siglock);
- if (retval) {
- up_write(&mm->mmap_sem);
+ retval = coredump_wait(exit_code);
+ if (retval < 0)
goto fail;
- }
-
- init_completion(&mm->core_done);
- coredump_wait(mm);
/*
* Clear any false indication of pending signals that might
lock_kernel();
format_corename(corename, core_pattern, signr);
unlock_kernel();
- file = filp_open(corename, O_CREAT | 2 | O_NOFOLLOW | O_LARGEFILE | flag, 0600);
+ if (corename[0] == '|') {
+ /* SIGPIPE can happen, but it's just never processed */
+ if(call_usermodehelper_pipe(corename+1, NULL, NULL, &file)) {
+ printk(KERN_INFO "Core dump to %s pipe failed\n",
+ corename);
+ goto fail_unlock;
+ }
+ ispipe = 1;
+ } else
+ file = filp_open(corename,
+ O_CREAT | 2 | O_NOFOLLOW | O_LARGEFILE, 0600);
if (IS_ERR(file))
goto fail_unlock;
inode = file->f_dentry->d_inode;
if (inode->i_nlink > 1)
goto close_fail; /* multiple links - don't dump */
- if (d_unhashed(file->f_dentry))
+ if (!ispipe && d_unhashed(file->f_dentry))
goto close_fail;
- if (!S_ISREG(inode->i_mode))
+ /* AK: actually i see no reason to not allow this for named pipes etc.,
+ but keep the previous behaviour for now. */
+ if (!ispipe && !S_ISREG(inode->i_mode))
goto close_fail;
if (!file->f_op)
goto close_fail;
if (!file->f_op->write)
goto close_fail;
- if (do_truncate(file->f_dentry, 0, 0, file) != 0)
+ if (!ispipe && do_truncate(file->f_dentry, 0, 0, file) != 0)
goto close_fail;
retval = binfmt->core_dump(signr, regs, file);
Code Review / linux-2.6.git / blobdiff