/*
* External references and all of the globals.
*/
-static void do_acct_process(struct pid_namespace *ns, struct file *);
+static void do_acct_process(struct bsd_acct_struct *acct,
+ struct pid_namespace *ns, struct file *);
/*
* This structure is used so that all the data protected by lock
struct file *file;
struct pid_namespace *ns;
struct timer_list timer;
+ struct list_head list;
};
static DEFINE_SPINLOCK(acct_lock);
-
-static struct bsd_acct_struct acct_globals __cacheline_aligned;
+static LIST_HEAD(acct_list);
/*
* Called whenever the timer says to check the free space.
/*
* Check the amount of free space and suspend/resume accordingly.
*/
-static int check_free_space(struct file *file)
+static int check_free_space(struct bsd_acct_struct *acct, struct file *file)
{
struct kstatfs sbuf;
int res;
sector_t suspend;
spin_lock(&acct_lock);
- res = acct_globals.active;
- if (!file || !acct_globals.needcheck)
+ res = acct->active;
+ if (!file || !acct->needcheck)
goto out;
spin_unlock(&acct_lock);
act = 0;
/*
- * If some joker switched acct_globals.file under us we'ld better be
+ * If some joker switched acct->file under us we'ld better be
* silent and _not_ touch anything.
*/
spin_lock(&acct_lock);
- if (file != acct_globals.file) {
+ if (file != acct->file) {
if (act)
res = act>0;
goto out;
}
- if (acct_globals.active) {
+ if (acct->active) {
if (act < 0) {
- acct_globals.active = 0;
+ acct->active = 0;
printk(KERN_INFO "Process accounting paused\n");
}
} else {
if (act > 0) {
- acct_globals.active = 1;
+ acct->active = 1;
printk(KERN_INFO "Process accounting resumed\n");
}
}
- del_timer(&acct_globals.timer);
- acct_globals.needcheck = 0;
- acct_globals.timer.expires = jiffies + ACCT_TIMEOUT*HZ;
- add_timer(&acct_globals.timer);
- res = acct_globals.active;
+ del_timer(&acct->timer);
+ acct->needcheck = 0;
+ acct->timer.expires = jiffies + ACCT_TIMEOUT*HZ;
+ add_timer(&acct->timer);
+ res = acct->active;
out:
spin_unlock(&acct_lock);
return res;
*
* NOTE: acct_lock MUST be held on entry and exit.
*/
-static void acct_file_reopen(struct file *file)
+static void acct_file_reopen(struct bsd_acct_struct *acct, struct file *file,
+ struct pid_namespace *ns)
{
struct file *old_acct = NULL;
struct pid_namespace *old_ns = NULL;
- if (acct_globals.file) {
- old_acct = acct_globals.file;
- old_ns = acct_globals.ns;
- del_timer(&acct_globals.timer);
- acct_globals.active = 0;
- acct_globals.needcheck = 0;
- acct_globals.file = NULL;
+ if (acct->file) {
+ old_acct = acct->file;
+ old_ns = acct->ns;
+ del_timer(&acct->timer);
+ acct->active = 0;
+ acct->needcheck = 0;
+ acct->file = NULL;
+ acct->ns = NULL;
+ list_del(&acct->list);
}
if (file) {
- acct_globals.file = file;
- acct_globals.ns = get_pid_ns(task_active_pid_ns(current));
- acct_globals.needcheck = 0;
- acct_globals.active = 1;
+ acct->file = file;
+ acct->ns = ns;
+ acct->needcheck = 0;
+ acct->active = 1;
+ list_add(&acct->list, &acct_list);
/* It's been deleted if it was used before so this is safe */
- setup_timer(&acct_globals.timer, acct_timeout,
- (unsigned long)&acct_globals);
- acct_globals.timer.expires = jiffies + ACCT_TIMEOUT*HZ;
- add_timer(&acct_globals.timer);
+ setup_timer(&acct->timer, acct_timeout, (unsigned long)acct);
+ acct->timer.expires = jiffies + ACCT_TIMEOUT*HZ;
+ add_timer(&acct->timer);
}
if (old_acct) {
mnt_unpin(old_acct->f_path.mnt);
spin_unlock(&acct_lock);
- do_acct_process(old_ns, old_acct);
+ do_acct_process(acct, old_ns, old_acct);
filp_close(old_acct, NULL);
- put_pid_ns(old_ns);
spin_lock(&acct_lock);
}
}
static int acct_on(char *name)
{
struct file *file;
+ struct vfsmount *mnt;
int error;
+ struct pid_namespace *ns;
+ struct bsd_acct_struct *acct = NULL;
/* Difference from BSD - they don't do O_APPEND */
file = filp_open(name, O_WRONLY|O_APPEND|O_LARGEFILE, 0);
return -EIO;
}
+ ns = task_active_pid_ns(current);
+ if (ns->bacct == NULL) {
+ acct = kzalloc(sizeof(struct bsd_acct_struct), GFP_KERNEL);
+ if (acct == NULL) {
+ filp_close(file, NULL);
+ return -ENOMEM;
+ }
+ }
+
error = security_acct(file);
if (error) {
+ kfree(acct);
filp_close(file, NULL);
return error;
}
spin_lock(&acct_lock);
- mnt_pin(file->f_path.mnt);
- acct_file_reopen(file);
+ if (ns->bacct == NULL) {
+ ns->bacct = acct;
+ acct = NULL;
+ }
+
+ mnt = file->f_path.mnt;
+ mnt_pin(mnt);
+ acct_file_reopen(ns->bacct, file, ns);
spin_unlock(&acct_lock);
- mntput(file->f_path.mnt); /* it's pinned, now give up active reference */
+ mntput(mnt); /* it's pinned, now give up active reference */
+ kfree(acct);
return 0;
}
* should be written. If the filename is NULL, accounting will be
* shutdown.
*/
-asmlinkage long sys_acct(const char __user *name)
+SYSCALL_DEFINE1(acct, const char __user *, name)
{
int error;
error = acct_on(tmp);
putname(tmp);
} else {
+ struct bsd_acct_struct *acct;
+
+ acct = task_active_pid_ns(current)->bacct;
+ if (acct == NULL)
+ return 0;
+
error = security_acct(NULL);
if (!error) {
spin_lock(&acct_lock);
- acct_file_reopen(NULL);
+ acct_file_reopen(acct, NULL, NULL);
spin_unlock(&acct_lock);
}
}
*/
void acct_auto_close_mnt(struct vfsmount *m)
{
+ struct bsd_acct_struct *acct;
+
spin_lock(&acct_lock);
- if (acct_globals.file && acct_globals.file->f_path.mnt == m)
- acct_file_reopen(NULL);
+restart:
+ list_for_each_entry(acct, &acct_list, list)
+ if (acct->file && acct->file->f_path.mnt == m) {
+ acct_file_reopen(acct, NULL, NULL);
+ goto restart;
+ }
spin_unlock(&acct_lock);
}
*/
void acct_auto_close(struct super_block *sb)
{
+ struct bsd_acct_struct *acct;
+
+ spin_lock(&acct_lock);
+restart:
+ list_for_each_entry(acct, &acct_list, list)
+ if (acct->file && acct->file->f_path.mnt->mnt_sb == sb) {
+ acct_file_reopen(acct, NULL, NULL);
+ goto restart;
+ }
+ spin_unlock(&acct_lock);
+}
+
+void acct_exit_ns(struct pid_namespace *ns)
+{
+ struct bsd_acct_struct *acct;
+
spin_lock(&acct_lock);
- if (acct_globals.file &&
- acct_globals.file->f_path.mnt->mnt_sb == sb) {
- acct_file_reopen(NULL);
+ acct = ns->bacct;
+ if (acct != NULL) {
+ if (acct->file != NULL)
+ acct_file_reopen(acct, NULL, NULL);
+
+ kfree(acct);
}
spin_unlock(&acct_lock);
}
/*
* do_acct_process does all actual work. Caller holds the reference to file.
*/
-static void do_acct_process(struct pid_namespace *ns, struct file *file)
+static void do_acct_process(struct bsd_acct_struct *acct,
+ struct pid_namespace *ns, struct file *file)
{
struct pacct_struct *pacct = ¤t->signal->pacct;
acct_t ac;
u64 run_time;
struct timespec uptime;
struct tty_struct *tty;
+ const struct cred *orig_cred;
+
+ /* Perform file operations on behalf of whoever enabled accounting */
+ orig_cred = override_creds(file->f_cred);
/*
* First check to see if there is enough free_space to continue
* the process accounting system.
*/
- if (!check_free_space(file))
- return;
+ if (!check_free_space(acct, file))
+ goto out;
/*
* Fill the accounting struct with the needed info as recorded
do_div(elapsed, AHZ);
ac.ac_btime = get_seconds() - elapsed;
/* we really need to bite the bullet and change layout */
- ac.ac_uid = current->uid;
- ac.ac_gid = current->gid;
+ ac.ac_uid = orig_cred->uid;
+ ac.ac_gid = orig_cred->gid;
#if ACCT_VERSION==2
ac.ac_ahz = AHZ;
#endif
#if ACCT_VERSION==1 || ACCT_VERSION==2
/* backward-compatible 16 bit fields */
- ac.ac_uid16 = current->uid;
- ac.ac_gid16 = current->gid;
+ ac.ac_uid16 = ac.ac_uid;
+ ac.ac_gid16 = ac.ac_gid;
#endif
#if ACCT_VERSION==3
ac.ac_pid = task_tgid_nr_ns(current, ns);
#endif
spin_lock_irq(¤t->sighand->siglock);
- tty = current->signal->tty;
+ tty = current->signal->tty; /* Safe as we hold the siglock */
ac.ac_tty = tty ? old_encode_dev(tty_devnum(tty)) : 0;
ac.ac_utime = encode_comp_t(jiffies_to_AHZ(cputime_to_jiffies(pacct->ac_utime)));
ac.ac_stime = encode_comp_t(jiffies_to_AHZ(cputime_to_jiffies(pacct->ac_stime)));
sizeof(acct_t), &file->f_pos);
current->signal->rlim[RLIMIT_FSIZE].rlim_cur = flim;
set_fs(fs);
+out:
+ revert_creds(orig_cred);
}
/**
spin_unlock_irq(¤t->sighand->siglock);
}
-/**
- * acct_process - now just a wrapper around do_acct_process
- *
- * handles process accounting for an exiting task
- */
-void acct_process(void)
+static void acct_process_in_ns(struct pid_namespace *ns)
{
struct file *file = NULL;
- struct pid_namespace *ns;
+ struct bsd_acct_struct *acct;
+ acct = ns->bacct;
/*
* accelerate the common fastpath:
*/
- if (!acct_globals.file)
+ if (!acct || !acct->file)
return;
spin_lock(&acct_lock);
- file = acct_globals.file;
+ file = acct->file;
if (unlikely(!file)) {
spin_unlock(&acct_lock);
return;
}
get_file(file);
- ns = get_pid_ns(acct_globals.ns);
spin_unlock(&acct_lock);
- do_acct_process(ns, file);
+ do_acct_process(acct, ns, file);
fput(file);
- put_pid_ns(ns);
+}
+
+/**
+ * acct_process - now just a wrapper around acct_process_in_ns,
+ * which in turn is a wrapper around do_acct_process.
+ *
+ * handles process accounting for an exiting task
+ */
+void acct_process(void)
+{
+ struct pid_namespace *ns;
+
+ /*
+ * This loop is safe lockless, since current is still
+ * alive and holds its namespace, which in turn holds
+ * its parent.
+ */
+ for (ns = task_active_pid_ns(current); ns != NULL; ns = ns->parent)
+ acct_process_in_ns(ns);
}
git://ftp.safe.ca / safe / jmp / linux-2.6 / blobdiff