vserver 1.9.3
[linux-2.6.git] / kernel / sys.c
index 4d414d9..1ba0e4c 100644 (file)
@@ -12,6 +12,7 @@
 #include <linux/mman.h>
 #include <linux/smp_lock.h>
 #include <linux/notifier.h>
+#include <linux/kmod.h>
 #include <linux/reboot.h>
 #include <linux/prctl.h>
 #include <linux/init.h>
@@ -23,6 +24,8 @@
 #include <linux/security.h>
 #include <linux/dcookies.h>
 #include <linux/suspend.h>
+#include <linux/vs_base.h>
+#include <linux/vs_cvirt.h>
 
 #include <asm/uaccess.h>
 #include <asm/io.h>
@@ -271,6 +274,12 @@ cond_syscall(compat_sys_mq_timedsend)
 cond_syscall(compat_sys_mq_timedreceive)
 cond_syscall(compat_sys_mq_notify)
 cond_syscall(compat_sys_mq_getsetattr)
+cond_syscall(sys_mbind)
+cond_syscall(sys_get_mempolicy)
+cond_syscall(sys_set_mempolicy)
+cond_syscall(compat_mbind)
+cond_syscall(compat_get_mempolicy)
+cond_syscall(compat_set_mempolicy)
 
 /* arch-specific weak syscall entries */
 cond_syscall(sys_pciconfig_read)
@@ -287,7 +296,10 @@ static int set_one_prio(struct task_struct *p, int niceval, int error)
                goto out;
        }
        if (niceval < task_nice(p) && !capable(CAP_SYS_NICE)) {
-               error = -EACCES;
+               if (vx_flags(VXF_IGNEG_NICE, 0))
+                       error = 0;
+               else
+                       error = -EACCES;
                goto out;
        }
        no_nice = security_task_setnice(p, niceval);
@@ -306,8 +318,6 @@ asmlinkage long sys_setpriority(int which, int who, int niceval)
 {
        struct task_struct *g, *p;
        struct user_struct *user;
-       struct pid *pid;
-       struct list_head *l;
        int error = -EINVAL;
 
        if (which > 2 || which < 0)
@@ -332,14 +342,15 @@ asmlinkage long sys_setpriority(int which, int who, int niceval)
                case PRIO_PGRP:
                        if (!who)
                                who = process_group(current);
-                       for_each_task_pid(who, PIDTYPE_PGID, p, l, pid)
+                       do_each_task_pid(who, PIDTYPE_PGID, p) {
                                error = set_one_prio(p, niceval, error);
+                       } while_each_task_pid(who, PIDTYPE_PGID, p);
                        break;
                case PRIO_USER:
                        if (!who)
                                user = current->user;
                        else
-                               user = find_user(who);
+                               user = find_user(vx_current_xid(), who);
 
                        if (!user)
                                goto out_unlock;
@@ -348,6 +359,8 @@ asmlinkage long sys_setpriority(int which, int who, int niceval)
                                if (p->uid == who)
                                        error = set_one_prio(p, niceval, error);
                        while_each_thread(g, p);
+                       if (who)
+                               free_uid(user);         /* For find_user() */
                        break;
        }
 out_unlock:
@@ -365,8 +378,6 @@ out:
 asmlinkage long sys_getpriority(int which, int who)
 {
        struct task_struct *g, *p;
-       struct list_head *l;
-       struct pid *pid;
        struct user_struct *user;
        long niceval, retval = -ESRCH;
 
@@ -388,17 +399,17 @@ asmlinkage long sys_getpriority(int which, int who)
                case PRIO_PGRP:
                        if (!who)
                                who = process_group(current);
-                       for_each_task_pid(who, PIDTYPE_PGID, p, l, pid) {
+                       do_each_task_pid(who, PIDTYPE_PGID, p) {
                                niceval = 20 - task_nice(p);
                                if (niceval > retval)
                                        retval = niceval;
-                       }
+                       } while_each_task_pid(who, PIDTYPE_PGID, p);
                        break;
                case PRIO_USER:
                        if (!who)
                                user = current->user;
                        else
-                               user = find_user(who);
+                               user = find_user(vx_current_xid(), who);
 
                        if (!user)
                                goto out_unlock;
@@ -410,6 +421,8 @@ asmlinkage long sys_getpriority(int which, int who)
                                                retval = niceval;
                                }
                        while_each_thread(g, p);
+                       if (who)
+                               free_uid(user);         /* for find_user() */
                        break;
        }
 out_unlock:
@@ -418,6 +431,7 @@ out_unlock:
        return retval;
 }
 
+long vs_reboot(unsigned int, void *);
 
 /*
  * Reboot system call: for obvious reasons only root may call it,
@@ -443,11 +457,14 @@ asmlinkage long sys_reboot(int magic1, int magic2, unsigned int cmd, void __user
                        magic2 != LINUX_REBOOT_MAGIC2C))
                return -EINVAL;
 
+       if (!vx_check(0, VX_ADMIN|VX_WATCH))
+               return vs_reboot(cmd, arg);
+
        lock_kernel();
        switch (cmd) {
        case LINUX_REBOOT_CMD_RESTART:
                notifier_call_chain(&reboot_notifier_list, SYS_RESTART, NULL);
-               system_state = SYSTEM_SHUTDOWN;
+               system_state = SYSTEM_RESTART;
                device_shutdown();
                printk(KERN_EMERG "Restarting system.\n");
                machine_restart(NULL);
@@ -463,7 +480,7 @@ asmlinkage long sys_reboot(int magic1, int magic2, unsigned int cmd, void __user
 
        case LINUX_REBOOT_CMD_HALT:
                notifier_call_chain(&reboot_notifier_list, SYS_HALT, NULL);
-               system_state = SYSTEM_SHUTDOWN;
+               system_state = SYSTEM_HALT;
                device_shutdown();
                printk(KERN_EMERG "System halted.\n");
                machine_halt();
@@ -473,7 +490,7 @@ asmlinkage long sys_reboot(int magic1, int magic2, unsigned int cmd, void __user
 
        case LINUX_REBOOT_CMD_POWER_OFF:
                notifier_call_chain(&reboot_notifier_list, SYS_POWER_OFF, NULL);
-               system_state = SYSTEM_SHUTDOWN;
+               system_state = SYSTEM_POWER_OFF;
                device_shutdown();
                printk(KERN_EMERG "Power down.\n");
                machine_power_off();
@@ -489,7 +506,7 @@ asmlinkage long sys_reboot(int magic1, int magic2, unsigned int cmd, void __user
                buffer[sizeof(buffer) - 1] = '\0';
 
                notifier_call_chain(&reboot_notifier_list, SYS_RESTART, buffer);
-               system_state = SYSTEM_SHUTDOWN;
+               system_state = SYSTEM_RESTART;
                device_shutdown();
                printk(KERN_EMERG "Restarting system with command '%s'.\n", buffer);
                machine_restart(buffer);
@@ -637,7 +654,7 @@ static int set_user(uid_t new_ruid, int dumpclear)
 {
        struct user_struct *new_user;
 
-       new_user = alloc_uid(new_ruid);
+       new_user = alloc_uid(vx_current_xid(), new_ruid);
        if (!new_user)
                return -EAGAIN;
 
@@ -812,7 +829,7 @@ asmlinkage long sys_setresuid(uid_t ruid, uid_t euid, uid_t suid)
        return security_task_post_setuid(old_ruid, old_euid, old_suid, LSM_SETID_RES);
 }
 
-asmlinkage long sys_getresuid(uid_t *ruid, uid_t *euid, uid_t *suid)
+asmlinkage long sys_getresuid(uid_t __user *ruid, uid_t __user *euid, uid_t __user *suid)
 {
        int retval;
 
@@ -861,7 +878,7 @@ asmlinkage long sys_setresgid(gid_t rgid, gid_t egid, gid_t sgid)
        return 0;
 }
 
-asmlinkage long sys_getresgid(gid_t *rgid, gid_t *egid, gid_t *sgid)
+asmlinkage long sys_getresgid(gid_t __user *rgid, gid_t __user *egid, gid_t __user *sgid)
 {
        int retval;
 
@@ -939,10 +956,39 @@ asmlinkage long sys_times(struct tms __user * tbuf)
         */
        if (tbuf) {
                struct tms tmp;
-               tmp.tms_utime = jiffies_to_clock_t(current->utime);
-               tmp.tms_stime = jiffies_to_clock_t(current->stime);
-               tmp.tms_cutime = jiffies_to_clock_t(current->cutime);
-               tmp.tms_cstime = jiffies_to_clock_t(current->cstime);
+               struct task_struct *tsk = current;
+               struct task_struct *t;
+               unsigned long utime, stime, cutime, cstime;
+
+               read_lock(&tasklist_lock);
+               utime = tsk->signal->utime;
+               stime = tsk->signal->stime;
+               t = tsk;
+               do {
+                       utime += t->utime;
+                       stime += t->stime;
+                       t = next_thread(t);
+               } while (t != tsk);
+
+               /*
+                * While we have tasklist_lock read-locked, no dying thread
+                * can be updating current->signal->[us]time.  Instead,
+                * we got their counts included in the live thread loop.
+                * However, another thread can come in right now and
+                * do a wait call that updates current->signal->c[us]time.
+                * To make sure we always see that pair updated atomically,
+                * we take the siglock around fetching them.
+                */
+               spin_lock_irq(&tsk->sighand->siglock);
+               cutime = tsk->signal->cutime;
+               cstime = tsk->signal->cstime;
+               spin_unlock_irq(&tsk->sighand->siglock);
+               read_unlock(&tasklist_lock);
+
+               tmp.tms_utime = jiffies_to_clock_t(utime);
+               tmp.tms_stime = jiffies_to_clock_t(stime);
+               tmp.tms_cutime = jiffies_to_clock_t(cutime);
+               tmp.tms_cstime = jiffies_to_clock_t(cstime);
                if (copy_to_user(tbuf, &tmp, sizeof(struct tms)))
                        return -EFAULT;
        }
@@ -966,14 +1012,17 @@ asmlinkage long sys_setpgid(pid_t pid, pid_t pgid)
 {
        struct task_struct *p;
        int err = -EINVAL;
+       pid_t rpgid;
 
        if (!pid)
-               pid = current->pid;
+               pid = vx_map_pid(current->pid);
        if (!pgid)
                pgid = pid;
        if (pgid < 0)
                return -EINVAL;
 
+       rpgid = vx_rmap_pid(pgid);
+
        /* From this point forward we keep holding onto the tasklist lock
         * so that our parent does not change from under us. -DaveM
         */
@@ -1007,24 +1056,23 @@ asmlinkage long sys_setpgid(pid_t pid, pid_t pgid)
 
        if (pgid != pid) {
                struct task_struct *p;
-               struct pid *pid;
-               struct list_head *l;
 
-               for_each_task_pid(pgid, PIDTYPE_PGID, p, l, pid)
+               do_each_task_pid(rpgid, PIDTYPE_PGID, p) {
                        if (p->signal->session == current->signal->session)
                                goto ok_pgid;
+               } while_each_task_pid(rpgid, PIDTYPE_PGID, p);
                goto out;
        }
 
 ok_pgid:
-       err = security_task_setpgid(p, pgid);
+       err = security_task_setpgid(p, rpgid);
        if (err)
                goto out;
 
-       if (process_group(p) != pgid) {
+       if (process_group(p) != rpgid) {
                detach_pid(p, PIDTYPE_PGID);
-               p->signal->pgrp = pgid;
-               attach_pid(p, PIDTYPE_PGID, pgid);
+               p->signal->pgrp = rpgid;
+               attach_pid(p, PIDTYPE_PGID, rpgid);
        }
 
        err = 0;
@@ -1037,7 +1085,7 @@ out:
 asmlinkage long sys_getpgid(pid_t pid)
 {
        if (!pid) {
-               return process_group(current);
+               return vx_rmap_pid(process_group(current));
        } else {
                int retval;
                struct task_struct *p;
@@ -1049,19 +1097,23 @@ asmlinkage long sys_getpgid(pid_t pid)
                if (p) {
                        retval = security_task_getpgid(p);
                        if (!retval)
-                               retval = process_group(p);
+                               retval = vx_rmap_pid(process_group(p));
                }
                read_unlock(&tasklist_lock);
                return retval;
        }
 }
 
+#ifdef __ARCH_WANT_SYS_GETPGRP
+
 asmlinkage long sys_getpgrp(void)
 {
        /* SMP - assuming writes are word atomic this is fine */
        return process_group(current);
 }
 
+#endif
+
 asmlinkage long sys_getsid(pid_t pid)
 {
        if (!pid) {
@@ -1121,10 +1173,10 @@ struct group_info *groups_alloc(int gidsetsize)
        int nblocks;
        int i;
 
-       nblocks = (gidsetsize/NGROUPS_PER_BLOCK) +
-           (gidsetsize%NGROUPS_PER_BLOCK?1:0);
-       group_info = kmalloc(sizeof(*group_info) + nblocks*sizeof(gid_t *),
-           GFP_USER);
+       nblocks = (gidsetsize + NGROUPS_PER_BLOCK - 1) / NGROUPS_PER_BLOCK;
+       /* Make sure we always allocate at least one indirect block pointer */
+       nblocks = nblocks ? : 1;
+       group_info = kmalloc(sizeof(*group_info) + nblocks*sizeof(gid_t *), GFP_USER);
        if (!group_info)
                return NULL;
        group_info->ngroups = gidsetsize;
@@ -1270,8 +1322,12 @@ int set_current_groups(struct group_info *group_info)
 
        groups_sort(group_info);
        get_group_info(group_info);
+
+       task_lock(current);
        old_info = current->group_info;
        current->group_info = group_info;
+       task_unlock(current);
+
        put_group_info(old_info);
 
        return 0;
@@ -1291,6 +1347,7 @@ asmlinkage long sys_getgroups(int gidsetsize, gid_t __user *grouplist)
        if (gidsetsize < 0)
                return -EINVAL;
 
+       /* no need to grab task_lock here; it cannot change */
        get_group_info(current->group_info);
        i = current->group_info->ngroups;
        if (gidsetsize) {
@@ -1376,7 +1433,7 @@ asmlinkage long sys_newuname(struct new_utsname __user * name)
        int errno = 0;
 
        down_read(&uts_sem);
-       if (copy_to_user(name,&system_utsname,sizeof *name))
+       if (copy_to_user(name, vx_new_utsname(), sizeof *name))
                errno = -EFAULT;
        up_read(&uts_sem);
        return errno;
@@ -1387,38 +1444,46 @@ asmlinkage long sys_sethostname(char __user *name, int len)
        int errno;
        char tmp[__NEW_UTS_LEN];
 
-       if (!capable(CAP_SYS_ADMIN))
+       if (!capable(CAP_SYS_ADMIN) && !vx_ccaps(VXC_SET_UTSNAME))
                return -EPERM;
        if (len < 0 || len > __NEW_UTS_LEN)
                return -EINVAL;
        down_write(&uts_sem);
        errno = -EFAULT;
        if (!copy_from_user(tmp, name, len)) {
-               memcpy(system_utsname.nodename, tmp, len);
-               system_utsname.nodename[len] = 0;
+               char *ptr = vx_new_uts(nodename);
+
+               memcpy(ptr, tmp, len);
+               ptr[len] = 0;
                errno = 0;
        }
        up_write(&uts_sem);
        return errno;
 }
 
+#ifdef __ARCH_WANT_SYS_GETHOSTNAME
+
 asmlinkage long sys_gethostname(char __user *name, int len)
 {
        int i, errno;
+       char *ptr;
 
        if (len < 0)
                return -EINVAL;
        down_read(&uts_sem);
-       i = 1 + strlen(system_utsname.nodename);
+       ptr = vx_new_uts(nodename);
+       i = 1 + strlen(ptr);
        if (i > len)
                i = len;
        errno = 0;
-       if (copy_to_user(name, system_utsname.nodename, i))
+       if (copy_to_user(name, ptr, i))
                errno = -EFAULT;
        up_read(&uts_sem);
        return errno;
 }
 
+#endif
+
 /*
  * Only setdomainname; getdomainname can be implemented by calling
  * uname()
@@ -1428,7 +1493,7 @@ asmlinkage long sys_setdomainname(char __user *name, int len)
        int errno;
        char tmp[__NEW_UTS_LEN];
 
-       if (!capable(CAP_SYS_ADMIN))
+       if (!capable(CAP_SYS_ADMIN) && !vx_ccaps(VXC_SET_UTSNAME))
                return -EPERM;
        if (len < 0 || len > __NEW_UTS_LEN)
                return -EINVAL;
@@ -1436,8 +1501,10 @@ asmlinkage long sys_setdomainname(char __user *name, int len)
        down_write(&uts_sem);
        errno = -EFAULT;
        if (!copy_from_user(tmp, name, len)) {
-               memcpy(system_utsname.domainname, tmp, len);
-               system_utsname.domainname[len] = 0;
+               char *ptr = vx_new_uts(domainname);
+
+               memcpy(ptr, tmp, len);
+               ptr[len] = 0;
                errno = 0;
        }
        up_write(&uts_sem);
@@ -1453,7 +1520,7 @@ asmlinkage long sys_getrlimit(unsigned int resource, struct rlimit __user *rlim)
                        ? -EFAULT : 0;
 }
 
-#if defined(COMPAT_RLIM_OLD_INFINITY) || !(defined(CONFIG_IA64) || defined(CONFIG_V850))
+#ifdef __ARCH_WANT_SYS_OLD_GETRLIMIT
 
 /*
  *     Back compatibility for getrlimit. Needed for some apps.
@@ -1489,7 +1556,7 @@ asmlinkage long sys_setrlimit(unsigned int resource, struct rlimit __user *rlim)
        old_rlim = current->rlim + resource;
        if (((new_rlim.rlim_cur > old_rlim->rlim_max) ||
             (new_rlim.rlim_max > old_rlim->rlim_max)) &&
-           !capable(CAP_SYS_RESOURCE))
+           !capable(CAP_SYS_RESOURCE) && !vx_ccaps(VXC_SET_RLIMIT))
                return -EPERM;
        if (resource == RLIMIT_NOFILE) {
                if (new_rlim.rlim_cur > NR_OPEN || new_rlim.rlim_max > NR_OPEN)
@@ -1512,44 +1579,86 @@ asmlinkage long sys_setrlimit(unsigned int resource, struct rlimit __user *rlim)
  * a lot simpler!  (Which we're not doing right now because we're not
  * measuring them yet).
  *
- * This is SMP safe.  Either we are called from sys_getrusage on ourselves
- * below (we know we aren't going to exit/disappear and only we change our
- * rusage counters), or we are called from wait4() on a process which is
- * either stopped or zombied.  In the zombied case the task won't get
- * reaped till shortly after the call to getrusage(), in both cases the
- * task being examined is in a frozen state so the counters won't change.
+ * This expects to be called with tasklist_lock read-locked or better,
+ * and the siglock not locked.  It may momentarily take the siglock.
+ *
+ * When sampling multiple threads for RUSAGE_SELF, under SMP we might have
+ * races with threads incrementing their own counters.  But since word
+ * reads are atomic, we either get new values or old values and we don't
+ * care which for the sums.  We always take the siglock to protect reading
+ * the c* fields from p->signal from races with exit.c updating those
+ * fields when reaping, so a sample either gets all the additions of a
+ * given child after it's reaped, or none so this sample is before reaping.
  */
-int getrusage(struct task_struct *p, int who, struct rusage __user *ru)
+
+void k_getrusage(struct task_struct *p, int who, struct rusage *r)
 {
-       struct rusage r;
+       struct task_struct *t;
+       unsigned long flags;
+       unsigned long utime, stime;
+
+       memset((char *) r, 0, sizeof *r);
+
+       if (unlikely(!p->signal))
+               return;
 
-       memset((char *) &r, 0, sizeof(r));
        switch (who) {
-               case RUSAGE_SELF:
-                       jiffies_to_timeval(p->utime, &r.ru_utime);
-                       jiffies_to_timeval(p->stime, &r.ru_stime);
-                       r.ru_nvcsw = p->nvcsw;
-                       r.ru_nivcsw = p->nivcsw;
-                       r.ru_minflt = p->min_flt;
-                       r.ru_majflt = p->maj_flt;
-                       break;
                case RUSAGE_CHILDREN:
-                       jiffies_to_timeval(p->cutime, &r.ru_utime);
-                       jiffies_to_timeval(p->cstime, &r.ru_stime);
-                       r.ru_nvcsw = p->cnvcsw;
-                       r.ru_nivcsw = p->cnivcsw;
-                       r.ru_minflt = p->cmin_flt;
-                       r.ru_majflt = p->cmaj_flt;
+                       spin_lock_irqsave(&p->sighand->siglock, flags);
+                       utime = p->signal->cutime;
+                       stime = p->signal->cstime;
+                       r->ru_nvcsw = p->signal->cnvcsw;
+                       r->ru_nivcsw = p->signal->cnivcsw;
+                       r->ru_minflt = p->signal->cmin_flt;
+                       r->ru_majflt = p->signal->cmaj_flt;
+                       spin_unlock_irqrestore(&p->sighand->siglock, flags);
+                       jiffies_to_timeval(utime, &r->ru_utime);
+                       jiffies_to_timeval(stime, &r->ru_stime);
                        break;
-               default:
-                       jiffies_to_timeval(p->utime + p->cutime, &r.ru_utime);
-                       jiffies_to_timeval(p->stime + p->cstime, &r.ru_stime);
-                       r.ru_nvcsw = p->nvcsw + p->cnvcsw;
-                       r.ru_nivcsw = p->nivcsw + p->cnivcsw;
-                       r.ru_minflt = p->min_flt + p->cmin_flt;
-                       r.ru_majflt = p->maj_flt + p->cmaj_flt;
+               case RUSAGE_SELF:
+                       spin_lock_irqsave(&p->sighand->siglock, flags);
+                       utime = stime = 0;
+                       goto sum_group;
+               case RUSAGE_BOTH:
+                       spin_lock_irqsave(&p->sighand->siglock, flags);
+                       utime = p->signal->cutime;
+                       stime = p->signal->cstime;
+                       r->ru_nvcsw = p->signal->cnvcsw;
+                       r->ru_nivcsw = p->signal->cnivcsw;
+                       r->ru_minflt = p->signal->cmin_flt;
+                       r->ru_majflt = p->signal->cmaj_flt;
+               sum_group:
+                       utime += p->signal->utime;
+                       stime += p->signal->stime;
+                       r->ru_nvcsw += p->signal->nvcsw;
+                       r->ru_nivcsw += p->signal->nivcsw;
+                       r->ru_minflt += p->signal->min_flt;
+                       r->ru_majflt += p->signal->maj_flt;
+                       t = p;
+                       do {
+                               utime += t->utime;
+                               stime += t->stime;
+                               r->ru_nvcsw += t->nvcsw;
+                               r->ru_nivcsw += t->nivcsw;
+                               r->ru_minflt += t->min_flt;
+                               r->ru_majflt += t->maj_flt;
+                               t = next_thread(t);
+                       } while (t != p);
+                       spin_unlock_irqrestore(&p->sighand->siglock, flags);
+                       jiffies_to_timeval(utime, &r->ru_utime);
+                       jiffies_to_timeval(stime, &r->ru_stime);
                        break;
+               default:
+                       BUG();
        }
+}
+
+int getrusage(struct task_struct *p, int who, struct rusage __user *ru)
+{
+       struct rusage r;
+       read_lock(&tasklist_lock);
+       k_getrusage(p, who, &r);
+       read_unlock(&tasklist_lock);
        return copy_to_user(ru, &r, sizeof(r)) ? -EFAULT : 0;
 }
 
@@ -1639,6 +1748,17 @@ asmlinkage long sys_prctl(int option, unsigned long arg2, unsigned long arg3,
                        }
                        current->keep_capabilities = arg2;
                        break;
+               case PR_SET_NAME: {
+                       struct task_struct *me = current;
+                       unsigned char ncomm[sizeof(me->comm)];
+
+                       ncomm[sizeof(me->comm)-1] = 0;
+                       if (strncpy_from_user(ncomm, (char __user *)arg2,
+                                               sizeof(me->comm)-1) < 0)
+                               return -EFAULT;
+                       set_task_comm(me, ncomm);
+                       return 0;
+               }
                default:
                        error = -EINVAL;
                        break;