#include <asm/uaccess.h>
+#include <linux/config.h>
#include <linux/errno.h>
#include <linux/time.h>
#include <linux/proc_fs.h>
#include <linux/cpuset.h>
#include <linux/audit.h>
#include <linux/poll.h>
-#include <linux/vs_context.h>
+#include <linux/vs_cvirt.h>
#include <linux/vs_network.h>
-
#include "internal.h"
-/* NOTE:
- * Implementing inode permission operations in /proc is almost
- * certainly an error. Permission checks need to happen during
- * each system call not at open time. The reason is that most of
- * what we wish to check for permissions in /proc varies at runtime.
- *
- * The classic example of a problem is opening file descriptors
- * in /proc for a task before it execs a suid executable.
- */
-
/*
* For hysterical raisins we keep the same inumbers as in the old procfs.
* Feel free to change the macro below - just keep the range distinct from
PROC_TGID_MAPS,
PROC_TGID_NUMA_MAPS,
PROC_TGID_MOUNTS,
- PROC_TGID_MOUNTSTATS,
PROC_TGID_WCHAN,
#ifdef CONFIG_MMU
PROC_TGID_SMAPS,
PROC_TGID_ATTR_PREV,
PROC_TGID_ATTR_EXEC,
PROC_TGID_ATTR_FSCREATE,
- PROC_TGID_ATTR_KEYCREATE,
- PROC_TGID_ATTR_SOCKCREATE,
#endif
PROC_TGID_VX_INFO,
PROC_TGID_IP_INFO,
PROC_TID_MAPS,
PROC_TID_NUMA_MAPS,
PROC_TID_MOUNTS,
- PROC_TID_MOUNTSTATS,
PROC_TID_WCHAN,
#ifdef CONFIG_MMU
PROC_TID_SMAPS,
PROC_TID_ATTR_PREV,
PROC_TID_ATTR_EXEC,
PROC_TID_ATTR_FSCREATE,
- PROC_TID_ATTR_KEYCREATE,
- PROC_TID_ATTR_SOCKCREATE,
#endif
PROC_TID_VX_INFO,
PROC_TID_IP_INFO,
PROC_TID_FD_DIR = 0x8000, /* 0x8000-0xffff */
};
-/* Worst case buffer size needed for holding an integer. */
-#define PROC_NUMBUF 10
-
struct pid_entry {
int type;
int len;
E(PROC_TGID_CMDLINE, "cmdline", S_IFREG|S_IRUGO),
E(PROC_TGID_STAT, "stat", S_IFREG|S_IRUGO),
E(PROC_TGID_STATM, "statm", S_IFREG|S_IRUGO),
- E(PROC_TGID_MAPS, "maps", S_IFREG|S_IRUSR),
+ E(PROC_TGID_MAPS, "maps", S_IFREG|S_IRUGO),
#ifdef CONFIG_NUMA
E(PROC_TGID_NUMA_MAPS, "numa_maps", S_IFREG|S_IRUGO),
#endif
E(PROC_TGID_ROOT, "root", S_IFLNK|S_IRWXUGO),
E(PROC_TGID_EXE, "exe", S_IFLNK|S_IRWXUGO),
E(PROC_TGID_MOUNTS, "mounts", S_IFREG|S_IRUGO),
- E(PROC_TGID_MOUNTSTATS, "mountstats", S_IFREG|S_IRUSR),
#ifdef CONFIG_MMU
- E(PROC_TGID_SMAPS, "smaps", S_IFREG|S_IRUSR),
+ E(PROC_TGID_SMAPS, "smaps", S_IFREG|S_IRUGO),
#endif
#ifdef CONFIG_SECURITY
E(PROC_TGID_ATTR, "attr", S_IFDIR|S_IRUGO|S_IXUGO),
E(PROC_TID_CMDLINE, "cmdline", S_IFREG|S_IRUGO),
E(PROC_TID_STAT, "stat", S_IFREG|S_IRUGO),
E(PROC_TID_STATM, "statm", S_IFREG|S_IRUGO),
- E(PROC_TID_MAPS, "maps", S_IFREG|S_IRUSR),
+ E(PROC_TID_MAPS, "maps", S_IFREG|S_IRUGO),
#ifdef CONFIG_NUMA
E(PROC_TID_NUMA_MAPS, "numa_maps", S_IFREG|S_IRUGO),
#endif
E(PROC_TID_EXE, "exe", S_IFLNK|S_IRWXUGO),
E(PROC_TID_MOUNTS, "mounts", S_IFREG|S_IRUGO),
#ifdef CONFIG_MMU
- E(PROC_TID_SMAPS, "smaps", S_IFREG|S_IRUSR),
+ E(PROC_TID_SMAPS, "smaps", S_IFREG|S_IRUGO),
#endif
#ifdef CONFIG_SECURITY
E(PROC_TID_ATTR, "attr", S_IFDIR|S_IRUGO|S_IXUGO),
E(PROC_TGID_ATTR_PREV, "prev", S_IFREG|S_IRUGO),
E(PROC_TGID_ATTR_EXEC, "exec", S_IFREG|S_IRUGO|S_IWUGO),
E(PROC_TGID_ATTR_FSCREATE, "fscreate", S_IFREG|S_IRUGO|S_IWUGO),
- E(PROC_TGID_ATTR_KEYCREATE, "keycreate", S_IFREG|S_IRUGO|S_IWUGO),
- E(PROC_TGID_ATTR_SOCKCREATE, "sockcreate", S_IFREG|S_IRUGO|S_IWUGO),
{0,0,NULL,0}
};
static struct pid_entry tid_attr_stuff[] = {
E(PROC_TID_ATTR_PREV, "prev", S_IFREG|S_IRUGO),
E(PROC_TID_ATTR_EXEC, "exec", S_IFREG|S_IRUGO|S_IWUGO),
E(PROC_TID_ATTR_FSCREATE, "fscreate", S_IFREG|S_IRUGO|S_IWUGO),
- E(PROC_TID_ATTR_KEYCREATE, "keycreate", S_IFREG|S_IRUGO|S_IWUGO),
- E(PROC_TID_ATTR_SOCKCREATE, "sockcreate", S_IFREG|S_IRUGO|S_IWUGO),
{0,0,NULL,0}
};
#endif
static int proc_fd_link(struct inode *inode, struct dentry **dentry, struct vfsmount **mnt)
{
- struct task_struct *task = get_proc_task(inode);
- struct files_struct *files = NULL;
+ struct task_struct *task = proc_task(inode);
+ struct files_struct *files;
struct file *file;
- int fd = proc_fd(inode);
+ int fd = proc_type(inode) - PROC_TID_FD_DIR;
- if (task) {
- files = get_files_struct(task);
- put_task_struct(task);
- }
+ files = get_files_struct(task);
if (files) {
/*
* We are not taking a ref to the file structure, so we must
return fs;
}
-static int get_nr_threads(struct task_struct *tsk)
-{
- /* Must be called with the rcu_read_lock held */
- unsigned long flags;
- int count = 0;
-
- if (lock_task_sighand(tsk, &flags)) {
- count = atomic_read(&tsk->signal->count);
- unlock_task_sighand(tsk, &flags);
- }
- return count;
-}
-
static int proc_cwd_link(struct inode *inode, struct dentry **dentry, struct vfsmount **mnt)
{
- struct task_struct *task = get_proc_task(inode);
- struct fs_struct *fs = NULL;
+ struct fs_struct *fs = get_fs_struct(proc_task(inode));
int result = -ENOENT;
-
- if (task) {
- fs = get_fs_struct(task);
- put_task_struct(task);
- }
if (fs) {
read_lock(&fs->lock);
*mnt = mntget(fs->pwdmnt);
static int proc_root_link(struct inode *inode, struct dentry **dentry, struct vfsmount **mnt)
{
- struct task_struct *task = get_proc_task(inode);
- struct fs_struct *fs = NULL;
+ struct fs_struct *fs = get_fs_struct(proc_task(inode));
+ int result = -ENOENT;
+ if (fs) {
+ read_lock(&fs->lock);
+ *mnt = mntget(fs->rootmnt);
+ *dentry = dget(fs->root);
+ read_unlock(&fs->lock);
+ result = 0;
+ put_fs_struct(fs);
+ }
+ return result;
+}
+
+
+/* Same as proc_root_link, but this addionally tries to get fs from other
+ * threads in the group */
+static int proc_task_root_link(struct inode *inode, struct dentry **dentry,
+ struct vfsmount **mnt)
+{
+ struct fs_struct *fs;
int result = -ENOENT;
+ struct task_struct *leader = proc_task(inode);
- if (task) {
- fs = get_fs_struct(task);
- put_task_struct(task);
+ task_lock(leader);
+ fs = leader->fs;
+ if (fs) {
+ atomic_inc(&fs->count);
+ task_unlock(leader);
+ } else {
+ /* Try to get fs from other threads */
+ task_unlock(leader);
+ read_lock(&tasklist_lock);
+ if (pid_alive(leader)) {
+ struct task_struct *task = leader;
+
+ while ((task = next_thread(task)) != leader) {
+ task_lock(task);
+ fs = task->fs;
+ if (fs) {
+ atomic_inc(&fs->count);
+ task_unlock(task);
+ break;
+ }
+ task_unlock(task);
+ }
+ }
+ read_unlock(&tasklist_lock);
}
+
if (fs) {
read_lock(&fs->lock);
*mnt = mntget(fs->rootmnt);
return result;
}
+
#define MAY_PTRACE(task) \
(task == current || \
(task->parent == current && \
(task->state == TASK_STOPPED || task->state == TASK_TRACED) && \
security_ptrace(current,task) == 0))
-struct mm_struct *mm_for_maps(struct task_struct *task)
-{
- struct mm_struct *mm = get_task_mm(task);
- if (!mm)
- return NULL;
- down_read(&mm->mmap_sem);
- task_lock(task);
- if (task->mm != mm)
- goto out;
- if (task->mm != current->mm && __ptrace_may_attach(task) < 0)
- goto out;
- task_unlock(task);
- return mm;
-out:
- task_unlock(task);
- up_read(&mm->mmap_sem);
- mmput(mm);
- return NULL;
-}
-
static int proc_pid_environ(struct task_struct *task, char * buffer)
{
int res = 0;
/************************************************************************/
/* permission checks */
-static int proc_fd_access_allowed(struct inode *inode)
+
+/* If the process being read is separated by chroot from the reading process,
+ * don't let the reader access the threads.
+ */
+static int proc_check_chroot(struct dentry *root, struct vfsmount *vfsmnt)
{
- struct task_struct *task;
- int allowed = 0;
- /* Allow access to a task's file descriptors if it is us or we
- * may use ptrace attach to the process and find out that
- * information.
- */
- task = get_proc_task(inode);
- if (task) {
- allowed = ptrace_may_attach(task);
- put_task_struct(task);
+ struct dentry *de, *base;
+ struct vfsmount *our_vfsmnt, *mnt;
+ int res = 0;
+
+ /* context admin override */
+ if (capable(CAP_CONTEXT))
+ goto override;
+
+ read_lock(¤t->fs->lock);
+ our_vfsmnt = mntget(current->fs->rootmnt);
+ base = dget(current->fs->root);
+ read_unlock(¤t->fs->lock);
+
+ spin_lock(&vfsmount_lock);
+ de = root;
+ mnt = vfsmnt;
+
+ while (mnt != our_vfsmnt) {
+ if (mnt == mnt->mnt_parent)
+ goto out;
+ de = mnt->mnt_mountpoint;
+ mnt = mnt->mnt_parent;
}
- return allowed;
+
+ if (!is_subdir(de, base))
+ goto out;
+ spin_unlock(&vfsmount_lock);
+
+exit:
+ dput(base);
+ mntput(our_vfsmnt);
+override:
+ dput(root);
+ mntput(vfsmnt);
+ return res;
+out:
+ spin_unlock(&vfsmount_lock);
+ res = -EACCES;
+ goto exit;
+}
+
+static int proc_check_root(struct inode *inode)
+{
+ struct dentry *root;
+ struct vfsmount *vfsmnt;
+
+ if (proc_root_link(inode, &root, &vfsmnt)) /* Ewww... */
+ return -ENOENT;
+ return proc_check_chroot(root, vfsmnt);
+}
+
+static int proc_permission(struct inode *inode, int mask, struct nameidata *nd)
+{
+ if (generic_permission(inode, mask, NULL) != 0)
+ return -EACCES;
+ return proc_check_root(inode);
}
static int proc_setattr(struct dentry *dentry, struct iattr *attr)
.setattr = proc_setattr,
};
+static int proc_task_permission(struct inode *inode, int mask, struct nameidata *nd)
+{
+ struct dentry *root;
+ struct vfsmount *vfsmnt;
+
+ if (generic_permission(inode, mask, NULL) != 0)
+ return -EACCES;
+
+ if (proc_task_root_link(inode, &root, &vfsmnt))
+ return -ENOENT;
+
+ return proc_check_chroot(root, vfsmnt);
+}
+
+extern struct seq_operations proc_pid_maps_op;
+static int maps_open(struct inode *inode, struct file *file)
+{
+ struct task_struct *task = proc_task(inode);
+ int ret = seq_open(file, &proc_pid_maps_op);
+ if (!ret) {
+ struct seq_file *m = file->private_data;
+ m->private = task;
+ }
+ return ret;
+}
+
+static struct file_operations proc_maps_operations = {
+ .open = maps_open,
+ .read = seq_read,
+ .llseek = seq_lseek,
+ .release = seq_release,
+};
+
+#ifdef CONFIG_NUMA
+extern struct seq_operations proc_pid_numa_maps_op;
+static int numa_maps_open(struct inode *inode, struct file *file)
+{
+ struct task_struct *task = proc_task(inode);
+ int ret = seq_open(file, &proc_pid_numa_maps_op);
+ if (!ret) {
+ struct seq_file *m = file->private_data;
+ m->private = task;
+ }
+ return ret;
+}
+
+static struct file_operations proc_numa_maps_operations = {
+ .open = numa_maps_open,
+ .read = seq_read,
+ .llseek = seq_lseek,
+ .release = seq_release,
+};
+#endif
+
+#ifdef CONFIG_MMU
+extern struct seq_operations proc_pid_smaps_op;
+static int smaps_open(struct inode *inode, struct file *file)
+{
+ struct task_struct *task = proc_task(inode);
+ int ret = seq_open(file, &proc_pid_smaps_op);
+ if (!ret) {
+ struct seq_file *m = file->private_data;
+ m->private = task;
+ }
+ return ret;
+}
+
+static struct file_operations proc_smaps_operations = {
+ .open = smaps_open,
+ .read = seq_read,
+ .llseek = seq_lseek,
+ .release = seq_release,
+};
+#endif
+
extern struct seq_operations mounts_op;
struct proc_mounts {
struct seq_file m;
static int mounts_open(struct inode *inode, struct file *file)
{
- struct task_struct *task = get_proc_task(inode);
- struct namespace *namespace = NULL;
+ struct task_struct *task = proc_task(inode);
+ struct namespace *namespace;
struct proc_mounts *p;
int ret = -EINVAL;
- if (task) {
- task_lock(task);
- namespace = task->namespace;
- if (namespace)
- get_namespace(namespace);
- task_unlock(task);
- put_task_struct(task);
- }
+ task_lock(task);
+ namespace = task->namespace;
+ if (namespace)
+ get_namespace(namespace);
+ task_unlock(task);
if (namespace) {
ret = -ENOMEM;
.poll = mounts_poll,
};
-extern struct seq_operations mountstats_op;
-static int mountstats_open(struct inode *inode, struct file *file)
-{
- int ret = seq_open(file, &mountstats_op);
-
- if (!ret) {
- struct seq_file *m = file->private_data;
- struct namespace *namespace = NULL;
- struct task_struct *task = get_proc_task(inode);
-
- if (task) {
- task_lock(task);
- namespace = task->namespace;
- if (namespace)
- get_namespace(namespace);
- task_unlock(task);
- put_task_struct(task);
- }
-
- if (namespace)
- m->private = namespace;
- else {
- seq_release(inode, file);
- ret = -EINVAL;
- }
- }
- return ret;
-}
-
-static struct file_operations proc_mountstats_operations = {
- .open = mountstats_open,
- .read = seq_read,
- .llseek = seq_lseek,
- .release = mounts_release,
-};
-
#define PROC_BLOCK_SIZE (3*1024) /* 4K page size but our output routines use some slack for overruns */
static ssize_t proc_info_read(struct file * file, char __user * buf,
struct inode * inode = file->f_dentry->d_inode;
unsigned long page;
ssize_t length;
- struct task_struct *task = get_proc_task(inode);
-
- length = -ESRCH;
- if (!task)
- goto out_no_task;
+ struct task_struct *task = proc_task(inode);
if (count > PROC_BLOCK_SIZE)
count = PROC_BLOCK_SIZE;
-
- length = -ENOMEM;
if (!(page = __get_free_page(GFP_KERNEL)))
- goto out;
+ return -ENOMEM;
length = PROC_I(inode)->op.proc_read(task, (char*)page);
if (length >= 0)
length = simple_read_from_buffer(buf, count, ppos, (char *)page, length);
free_page(page);
-out:
- put_task_struct(task);
-out_no_task:
return length;
}
static ssize_t mem_read(struct file * file, char __user * buf,
size_t count, loff_t *ppos)
{
- struct task_struct *task = get_proc_task(file->f_dentry->d_inode);
+ struct task_struct *task = proc_task(file->f_dentry->d_inode);
char *page;
unsigned long src = *ppos;
int ret = -ESRCH;
struct mm_struct *mm;
- if (!task)
- goto out_no_task;
-
if (!MAY_PTRACE(task) || !ptrace_may_attach(task))
goto out;
out_free:
free_page((unsigned long) page);
out:
- put_task_struct(task);
-out_no_task:
return ret;
}
{
int copied = 0;
char *page;
- struct task_struct *task = get_proc_task(file->f_dentry->d_inode);
+ struct task_struct *task = proc_task(file->f_dentry->d_inode);
unsigned long dst = *ppos;
- copied = -ESRCH;
- if (!task)
- goto out_no_task;
-
if (!MAY_PTRACE(task) || !ptrace_may_attach(task))
- goto out;
+ return -ESRCH;
- copied = -ENOMEM;
page = (char *)__get_free_page(GFP_USER);
if (!page)
- goto out;
+ return -ENOMEM;
while (count > 0) {
int this_len, retval;
}
*ppos = dst;
free_page((unsigned long) page);
-out:
- put_task_struct(task);
-out_no_task:
return copied;
}
#endif
static ssize_t oom_adjust_read(struct file *file, char __user *buf,
size_t count, loff_t *ppos)
{
- struct task_struct *task = get_proc_task(file->f_dentry->d_inode);
- char buffer[PROC_NUMBUF];
+ struct task_struct *task = proc_task(file->f_dentry->d_inode);
+ char buffer[8];
size_t len;
- int oom_adjust;
+ int oom_adjust = task->oomkilladj;
loff_t __ppos = *ppos;
- if (!task)
- return -ESRCH;
- oom_adjust = task->oomkilladj;
- put_task_struct(task);
-
- len = snprintf(buffer, sizeof(buffer), "%i\n", oom_adjust);
+ len = sprintf(buffer, "%i\n", oom_adjust);
if (__ppos >= len)
return 0;
if (count > len-__ppos)
static ssize_t oom_adjust_write(struct file *file, const char __user *buf,
size_t count, loff_t *ppos)
{
- struct task_struct *task;
- char buffer[PROC_NUMBUF], *end;
+ struct task_struct *task = proc_task(file->f_dentry->d_inode);
+ char buffer[8], *end;
int oom_adjust;
if (!capable(CAP_SYS_RESOURCE))
return -EPERM;
- memset(buffer, 0, sizeof(buffer));
- if (count > sizeof(buffer) - 1)
- count = sizeof(buffer) - 1;
+ memset(buffer, 0, 8);
+ if (count > 6)
+ count = 6;
if (copy_from_user(buffer, buf, count))
return -EFAULT;
oom_adjust = simple_strtol(buffer, &end, 0);
return -EINVAL;
if (*end == '\n')
end++;
- task = get_proc_task(file->f_dentry->d_inode);
- if (!task)
- return -ESRCH;
task->oomkilladj = oom_adjust;
- put_task_struct(task);
if (end - buffer == 0)
return -EIO;
return end - buffer;
.write = oom_adjust_write,
};
+static struct inode_operations proc_mem_inode_operations = {
+ .permission = proc_permission,
+ .setattr = proc_setattr,
+};
+
#ifdef CONFIG_AUDITSYSCALL
#define TMPBUFLEN 21
static ssize_t proc_loginuid_read(struct file * file, char __user * buf,
size_t count, loff_t *ppos)
{
struct inode * inode = file->f_dentry->d_inode;
- struct task_struct *task = get_proc_task(inode);
+ struct task_struct *task = proc_task(inode);
ssize_t length;
char tmpbuf[TMPBUFLEN];
- if (!task)
- return -ESRCH;
length = scnprintf(tmpbuf, TMPBUFLEN, "%u",
audit_get_loginuid(task->audit_context));
- put_task_struct(task);
return simple_read_from_buffer(buf, count, ppos, tmpbuf, length);
}
struct inode * inode = file->f_dentry->d_inode;
char *page, *tmp;
ssize_t length;
+ struct task_struct *task = proc_task(inode);
uid_t loginuid;
if (!capable(CAP_AUDIT_CONTROL))
return -EPERM;
- if (current != pid_task(proc_pid(inode), PIDTYPE_PID))
+ if (current != task)
return -EPERM;
- if (count >= PAGE_SIZE)
- count = PAGE_SIZE - 1;
+ if (count > PAGE_SIZE)
+ count = PAGE_SIZE;
if (*ppos != 0) {
/* No partial writes. */
if (copy_from_user(page, buf, count))
goto out_free_page;
- page[count] = '\0';
loginuid = simple_strtoul(page, &tmp, 10);
if (tmp == page) {
length = -EINVAL;
goto out_free_page;
}
- length = audit_set_loginuid(current, loginuid);
+ length = audit_set_loginuid(task, loginuid);
if (likely(length == 0))
length = count;
static ssize_t seccomp_read(struct file *file, char __user *buf,
size_t count, loff_t *ppos)
{
- struct task_struct *tsk = get_proc_task(file->f_dentry->d_inode);
+ struct task_struct *tsk = proc_task(file->f_dentry->d_inode);
char __buf[20];
loff_t __ppos = *ppos;
size_t len;
- if (!tsk)
- return -ESRCH;
/* no need to print the trailing zero, so use only len */
len = sprintf(__buf, "%u\n", tsk->seccomp.mode);
- put_task_struct(tsk);
if (__ppos >= len)
return 0;
if (count > len - __ppos)
static ssize_t seccomp_write(struct file *file, const char __user *buf,
size_t count, loff_t *ppos)
{
- struct task_struct *tsk = get_proc_task(file->f_dentry->d_inode);
+ struct task_struct *tsk = proc_task(file->f_dentry->d_inode);
char __buf[20], *end;
unsigned int seccomp_mode;
- ssize_t result;
-
- result = -ESRCH;
- if (!tsk)
- goto out_no_task;
/* can set it only once to be even more secure */
- result = -EPERM;
if (unlikely(tsk->seccomp.mode))
- goto out;
+ return -EPERM;
- result = -EFAULT;
memset(__buf, 0, sizeof(__buf));
count = min(count, sizeof(__buf) - 1);
if (copy_from_user(__buf, buf, count))
- goto out;
-
+ return -EFAULT;
seccomp_mode = simple_strtoul(__buf, &end, 0);
if (*end == '\n')
end++;
- result = -EINVAL;
if (seccomp_mode && seccomp_mode <= NR_SECCOMP_MODES) {
tsk->seccomp.mode = seccomp_mode;
set_tsk_thread_flag(tsk, TIF_SECCOMP);
} else
- goto out;
- result = -EIO;
+ return -EINVAL;
if (unlikely(!(end - __buf)))
- goto out;
- result = end - __buf;
-out:
- put_task_struct(tsk);
-out_no_task:
- return result;
+ return -EIO;
+ return end - __buf;
}
static struct file_operations proc_seccomp_operations = {
/* We don't need a base pointer in the /proc filesystem */
path_release(nd);
- /* Are we allowed to snoop on the tasks file descriptors? */
- if (!proc_fd_access_allowed(inode))
+ if (current->fsuid != inode->i_uid && !capable(CAP_DAC_OVERRIDE))
+ goto out;
+ error = proc_check_root(inode);
+ if (error)
goto out;
error = PROC_I(inode)->op.proc_get_link(inode, &nd->dentry, &nd->mnt);
struct dentry *de;
struct vfsmount *mnt = NULL;
- /* Are we allowed to snoop on the tasks file descriptors? */
- if (!proc_fd_access_allowed(inode))
+ lock_kernel();
+
+ if (current->fsuid != inode->i_uid && !capable(CAP_DAC_OVERRIDE))
+ goto out;
+ error = proc_check_root(inode);
+ if (error)
goto out;
error = PROC_I(inode)->op.proc_get_link(inode, &de, &mnt);
dput(de);
mntput(mnt);
out:
+ unlock_kernel();
return error;
}
.setattr = proc_setattr,
};
+#define NUMBUF 10
+
static int proc_readfd(struct file * filp, void * dirent, filldir_t filldir)
{
- struct dentry *dentry = filp->f_dentry;
- struct inode *inode = dentry->d_inode;
- struct task_struct *p = get_proc_task(inode);
+ struct inode *inode = filp->f_dentry->d_inode;
+ struct task_struct *p = proc_task(inode);
unsigned int fd, tid, ino;
int retval;
- char buf[PROC_NUMBUF];
+ char buf[NUMBUF];
struct files_struct * files;
struct fdtable *fdt;
retval = -ENOENT;
- if (!p)
- goto out_no_task;
+ if (!pid_alive(p))
+ goto out;
retval = 0;
tid = p->pid;
goto out;
filp->f_pos++;
case 1:
- ino = parent_ino(dentry);
+ ino = fake_ino(tid, PROC_TID_INO);
if (filldir(dirent, "..", 2, 1, ino, DT_DIR) < 0)
goto out;
filp->f_pos++;
continue;
rcu_read_unlock();
- j = PROC_NUMBUF;
+ j = NUMBUF;
i = fd;
do {
j--;
} while (i);
ino = fake_ino(tid, PROC_TID_FD_DIR + fd);
- if (filldir(dirent, buf+j, PROC_NUMBUF-j, fd+2, ino, DT_LNK) < 0) {
+ if (filldir(dirent, buf+j, NUMBUF-j, fd+2, ino, DT_LNK) < 0) {
rcu_read_lock();
break;
}
put_files_struct(files);
}
out:
- put_task_struct(p);
-out_no_task:
return retval;
}
int pid;
struct dentry *dentry = filp->f_dentry;
struct inode *inode = dentry->d_inode;
- struct task_struct *task = get_proc_task(inode);
struct pid_entry *p;
ino_t ino;
int ret, hide;
ret = -ENOENT;
- if (!task)
+ if (!pid_alive(proc_task(inode)))
goto out;
ret = 0;
- pid = task->pid;
- put_task_struct(task);
+ pid = proc_task(inode)->pid;
i = filp->f_pos;
switch (i) {
case 0:
/* Common stuff */
ei = PROC_I(inode);
+ ei->task = NULL;
inode->i_mtime = inode->i_atime = inode->i_ctime = CURRENT_TIME;
inode->i_ino = fake_ino(task->pid, ino);
inode->i_op = &proc_def_inode_operations;
+ if (!pid_alive(task))
+ goto out_unlock;
+
/*
* grab the reference to task.
*/
- ei->pid = get_pid(task->pids[PIDTYPE_PID].pid);
- if (!ei->pid)
- goto out_unlock;
-
+ get_task_struct(task);
+ ei->task = task;
+ ei->type = ino;
inode->i_uid = 0;
inode->i_gid = 0;
- if (task_dumpable(task)) {
+ if (ino == PROC_TGID_INO || ino == PROC_TID_INO || task_dumpable(task)) {
inode->i_uid = task->euid;
inode->i_gid = task->egid;
}
return inode;
out_unlock:
+ ei->pde = NULL;
iput(inode);
return NULL;
}
*
* Rewrite the inode's ownerships here because the owning task may have
* performed a setuid(), etc.
- *
- * Before the /proc/pid/status file was created the only way to read
- * the effective uid of a /process was to stat /proc/pid. Reading
- * /proc/pid/status is slow enough that procps and other packages
- * kept stating /proc/pid. To keep the rules in /proc simple I have
- * made this apply to all per process world readable and executable
- * directories.
*/
static int pid_revalidate(struct dentry *dentry, struct nameidata *nd)
{
struct inode *inode = dentry->d_inode;
- struct task_struct *task = get_proc_task(inode);
- int ret = 0;
+ struct task_struct *task = proc_task(inode);
- if (task) {
- int pid = (inode->i_ino >> 16) & 0xFFFF;
+ if (!vx_check(vx_task_xid(task), VX_IDENT))
+ goto out_drop;
+ /* discard wrong fakeinit */
- if (!proc_pid_visible(task, pid))
- goto out_drop;
-
- ret = 1;
- if ((inode->i_mode == (S_IFDIR|S_IRUGO|S_IXUGO)) ||
- task_dumpable(task)) {
+ if (pid_alive(task)) {
+ if (proc_type(inode) == PROC_TGID_INO || proc_type(inode) == PROC_TID_INO || task_dumpable(task)) {
inode->i_uid = task->euid;
inode->i_gid = task->egid;
} else {
}
inode->i_mode &= ~(S_ISUID | S_ISGID);
security_task_to_inode(task, inode);
- goto out_put;
+ return 1;
}
out_drop:
d_drop(dentry);
-out_put:
- if (task)
- put_task_struct(task);
- return ret;
-}
-
-static int pid_getattr(struct vfsmount *mnt, struct dentry *dentry, struct kstat *stat)
-{
- struct inode *inode = dentry->d_inode;
- struct task_struct *task;
- generic_fillattr(inode, stat);
-
- rcu_read_lock();
- stat->uid = 0;
- stat->gid = 0;
- task = pid_task(proc_pid(inode), PIDTYPE_PID);
- if (task) {
- if ((inode->i_mode == (S_IFDIR|S_IRUGO|S_IXUGO)) ||
- task_dumpable(task)) {
- stat->uid = task->euid;
- stat->gid = task->egid;
- }
- }
- rcu_read_unlock();
return 0;
}
static int tid_fd_revalidate(struct dentry *dentry, struct nameidata *nd)
{
struct inode *inode = dentry->d_inode;
- struct task_struct *task = get_proc_task(inode);
- int fd = proc_fd(inode);
+ struct task_struct *task = proc_task(inode);
+ int fd = proc_type(inode) - PROC_TID_FD_DIR;
struct files_struct *files;
- if (task) {
- files = get_files_struct(task);
- if (files) {
- rcu_read_lock();
- if (fcheck_files(files, fd)) {
- rcu_read_unlock();
- put_files_struct(files);
- if (task_dumpable(task)) {
- inode->i_uid = task->euid;
- inode->i_gid = task->egid;
- } else {
- inode->i_uid = 0;
- inode->i_gid = 0;
- }
- inode->i_mode &= ~(S_ISUID | S_ISGID);
- security_task_to_inode(task, inode);
- put_task_struct(task);
- return 1;
- }
+ files = get_files_struct(task);
+ if (files) {
+ rcu_read_lock();
+ if (fcheck_files(files, fd)) {
rcu_read_unlock();
put_files_struct(files);
+ if (task_dumpable(task)) {
+ inode->i_uid = task->euid;
+ inode->i_gid = task->egid;
+ } else {
+ inode->i_uid = 0;
+ inode->i_gid = 0;
+ }
+ inode->i_mode &= ~(S_ISUID | S_ISGID);
+ security_task_to_inode(task, inode);
+ return 1;
}
- put_task_struct(task);
+ rcu_read_unlock();
+ put_files_struct(files);
}
d_drop(dentry);
return 0;
}
+static void pid_base_iput(struct dentry *dentry, struct inode *inode)
+{
+ struct task_struct *task = proc_task(inode);
+ spin_lock(&task->proc_lock);
+ if (task->proc_dentry == dentry)
+ task->proc_dentry = NULL;
+ spin_unlock(&task->proc_lock);
+ iput(inode);
+}
+
static int pid_delete_dentry(struct dentry * dentry)
{
/* Is the task we represent dead?
* If so, then don't put the dentry on the lru list,
* kill it immediately.
*/
- return !proc_pid(dentry->d_inode)->tasks[PIDTYPE_PID].first;
+ return !pid_alive(proc_task(dentry->d_inode));
}
static struct dentry_operations tid_fd_dentry_operations =
.d_delete = pid_delete_dentry,
};
+static struct dentry_operations pid_base_dentry_operations =
+{
+ .d_revalidate = pid_revalidate,
+ .d_iput = pid_base_iput,
+ .d_delete = pid_delete_dentry,
+};
+
/* Lookups */
static unsigned name_to_int(struct dentry *dentry)
/* SMP-safe */
static struct dentry *proc_lookupfd(struct inode * dir, struct dentry * dentry, struct nameidata *nd)
{
- struct task_struct *task = get_proc_task(dir);
+ struct task_struct *task = proc_task(dir);
unsigned fd = name_to_int(dentry);
- struct dentry *result = ERR_PTR(-ENOENT);
struct file * file;
struct files_struct * files;
struct inode *inode;
struct proc_inode *ei;
- if (!task)
- goto out_no_task;
if (fd == ~0U)
goto out;
+ if (!pid_alive(task))
+ goto out;
inode = proc_pid_make_inode(dir->i_sb, task, PROC_TID_FD_DIR+fd);
if (!inode)
goto out;
ei = PROC_I(inode);
- ei->fd = fd;
files = get_files_struct(task);
if (!files)
goto out_unlock;
ei->op.proc_get_link = proc_fd_link;
dentry->d_op = &tid_fd_dentry_operations;
d_add(dentry, inode);
- /* Close the race of the process dying before we return the dentry */
- if (tid_fd_revalidate(dentry, NULL))
- result = NULL;
-out:
- put_task_struct(task);
-out_no_task:
- return result;
+ return NULL;
out_unlock2:
spin_unlock(&files->file_lock);
put_files_struct(files);
out_unlock:
iput(inode);
- goto out;
+out:
+ return ERR_PTR(-ENOENT);
}
static int proc_task_readdir(struct file * filp, void * dirent, filldir_t filldir);
static struct dentry *proc_task_lookup(struct inode *dir, struct dentry * dentry, struct nameidata *nd);
-static int proc_task_getattr(struct vfsmount *mnt, struct dentry *dentry, struct kstat *stat);
static struct file_operations proc_fd_operations = {
.read = generic_read_dir,
*/
static struct inode_operations proc_fd_inode_operations = {
.lookup = proc_lookupfd,
+ .permission = proc_permission,
.setattr = proc_setattr,
};
static struct inode_operations proc_task_inode_operations = {
.lookup = proc_task_lookup,
- .getattr = proc_task_getattr,
+ .permission = proc_task_permission,
.setattr = proc_setattr,
};
struct inode * inode = file->f_dentry->d_inode;
unsigned long page;
ssize_t length;
- struct task_struct *task = get_proc_task(inode);
-
- length = -ESRCH;
- if (!task)
- goto out_no_task;
+ struct task_struct *task = proc_task(inode);
if (count > PAGE_SIZE)
count = PAGE_SIZE;
- length = -ENOMEM;
if (!(page = __get_free_page(GFP_KERNEL)))
- goto out;
+ return -ENOMEM;
length = security_getprocattr(task,
(char*)file->f_dentry->d_name.name,
if (length >= 0)
length = simple_read_from_buffer(buf, count, ppos, (char *)page, length);
free_page(page);
-out:
- put_task_struct(task);
-out_no_task:
return length;
}
struct inode * inode = file->f_dentry->d_inode;
char *page;
ssize_t length;
- struct task_struct *task = get_proc_task(inode);
+ struct task_struct *task = proc_task(inode);
- length = -ESRCH;
- if (!task)
- goto out_no_task;
if (count > PAGE_SIZE)
count = PAGE_SIZE;
-
- /* No partial writes. */
- length = -EINVAL;
- if (*ppos != 0)
- goto out;
-
- length = -ENOMEM;
+ if (*ppos != 0) {
+ /* No partial writes. */
+ return -EINVAL;
+ }
page = (char*)__get_free_page(GFP_USER);
if (!page)
- goto out;
-
+ return -ENOMEM;
length = -EFAULT;
if (copy_from_user(page, buf, count))
- goto out_free;
+ goto out;
length = security_setprocattr(task,
(char*)file->f_dentry->d_name.name,
(void*)page, count);
-out_free:
- free_page((unsigned long) page);
out:
- put_task_struct(task);
-out_no_task:
+ free_page((unsigned long) page);
return length;
}
extern int proc_pid_vx_info(struct task_struct *, char *);
extern int proc_pid_nx_info(struct task_struct *, char *);
+static int get_tid_list(int index, unsigned int *tids, struct inode *dir);
+
/* SMP-safe */
static struct dentry *proc_pident_lookup(struct inode *dir,
struct dentry *dentry,
struct pid_entry *ents)
{
struct inode *inode;
- struct dentry *error;
- struct task_struct *task = get_proc_task(dir);
+ int error;
+ struct task_struct *task = proc_task(dir);
struct pid_entry *p;
struct proc_inode *ei;
- error = ERR_PTR(-ENOENT);
+ error = -ENOENT;
inode = NULL;
- if (!task)
- goto out_no_task;
+ if (!pid_alive(task))
+ goto out;
for (p = ents; p->name; p++) {
if (p->len != dentry->d_name.len)
if (!p->name)
goto out;
- switch(p->type) {
- case PROC_TID_VX_INFO:
- case PROC_TGID_VX_INFO:
- case PROC_TID_IP_INFO:
- case PROC_TGID_IP_INFO:
- if (task_vx_flags(task, VXF_INFO_HIDE, 0))
- goto out;
- default:
- break;
+ switch (p->type) {
+ case PROC_TID_VX_INFO:
+ case PROC_TGID_VX_INFO:
+ case PROC_TID_IP_INFO:
+ case PROC_TGID_IP_INFO:
+ if (task_vx_flags(task, VXF_INFO_HIDE, 0))
+ goto out;
+ default:
+ break;
}
- error = ERR_PTR(-EINVAL);
+ error = -EINVAL;
inode = proc_pid_make_inode(dir->i_sb, task, p->type);
if (!inode)
goto out;
*/
switch(p->type) {
case PROC_TGID_TASK:
- inode->i_nlink = 2;
+ inode->i_nlink = 2 + get_tid_list(2, NULL, dir);
inode->i_op = &proc_task_inode_operations;
inode->i_fop = &proc_task_operations;
break;
#endif
case PROC_TID_MEM:
case PROC_TGID_MEM:
+ inode->i_op = &proc_mem_inode_operations;
inode->i_fop = &proc_mem_operations;
break;
#ifdef CONFIG_SECCOMP
inode->i_fop = &proc_smaps_operations;
break;
#endif
- case PROC_TID_MOUNTSTATS:
- case PROC_TGID_MOUNTSTATS:
- inode->i_fop = &proc_mountstats_operations;
- break;
#ifdef CONFIG_SECURITY
case PROC_TID_ATTR:
inode->i_nlink = 2;
case PROC_TGID_ATTR_EXEC:
case PROC_TID_ATTR_FSCREATE:
case PROC_TGID_ATTR_FSCREATE:
- case PROC_TID_ATTR_KEYCREATE:
- case PROC_TGID_ATTR_KEYCREATE:
- case PROC_TID_ATTR_SOCKCREATE:
- case PROC_TGID_ATTR_SOCKCREATE:
inode->i_fop = &proc_pid_attr_operations;
break;
#endif
break;
default:
printk("procfs: impossible type (%d)",p->type);
- iput(inode);
- error = ERR_PTR(-EINVAL);
- goto out;
+ error = -EINVAL;
+ goto out_put;
}
dentry->d_op = &pid_dentry_operations;
d_add(dentry, inode);
- /* Close the race of the process dying before we return the dentry */
- if (pid_revalidate(dentry, NULL))
- error = NULL;
+ return NULL;
+
+out_put:
+ iput(inode);
out:
- put_task_struct(task);
-out_no_task:
- return error;
+ return ERR_PTR(error);
}
static struct dentry *proc_tgid_base_lookup(struct inode *dir, struct dentry *dentry, struct nameidata *nd){
static struct inode_operations proc_tgid_base_inode_operations = {
.lookup = proc_tgid_base_lookup,
- .getattr = pid_getattr,
.setattr = proc_setattr,
};
static struct inode_operations proc_tid_base_inode_operations = {
.lookup = proc_tid_base_lookup,
- .getattr = pid_getattr,
.setattr = proc_setattr,
};
static struct inode_operations proc_tgid_attr_inode_operations = {
.lookup = proc_tgid_attr_lookup,
- .getattr = pid_getattr,
.setattr = proc_setattr,
};
static struct inode_operations proc_tid_attr_inode_operations = {
.lookup = proc_tid_attr_lookup,
- .getattr = pid_getattr,
.setattr = proc_setattr,
};
#endif
static int proc_self_readlink(struct dentry *dentry, char __user *buffer,
int buflen)
{
- char tmp[PROC_NUMBUF];
+ char tmp[30];
sprintf(tmp, "%d", vx_map_tgid(current->tgid));
return vfs_readlink(dentry,buffer,buflen,tmp);
}
static void *proc_self_follow_link(struct dentry *dentry, struct nameidata *nd)
{
- char tmp[PROC_NUMBUF];
+ char tmp[30];
sprintf(tmp, "%d", vx_map_tgid(current->tgid));
return ERR_PTR(vfs_follow_link(nd,tmp));
}
static struct inode_operations proc_self_inode_operations = {
.readlink = proc_self_readlink,
.follow_link = proc_self_follow_link,
+ .setattr = proc_setattr,
};
/**
- * proc_flush_task - Remove dcache entries for @task from the /proc dcache.
+ * proc_pid_unhash - Unhash /proc/@pid entry from the dcache.
+ * @p: task that should be flushed.
*
- * @task: task that should be flushed.
+ * Drops the /proc/@pid dcache entry from the hash chains.
*
- * Looks in the dcache for
- * /proc/@pid
- * /proc/@tgid/task/@pid
- * if either directory is present flushes it and all of it'ts children
- * from the dcache.
- *
- * It is safe and reasonable to cache /proc entries for a task until
- * that task exits. After that they just clog up the dcache with
- * useless entries, possibly causing useful dcache entries to be
- * flushed instead. This routine is proved to flush those useless
- * dcache entries at process exit time.
- *
- * NOTE: This routine is just an optimization so it does not guarantee
- * that no dcache entries will exist at process exit time it
- * just makes it very unlikely that any will persist.
+ * Dropping /proc/@pid entries and detach_pid must be synchroneous,
+ * otherwise e.g. /proc/@pid/exe might point to the wrong executable,
+ * if the pid value is immediately reused. This is enforced by
+ * - caller must acquire spin_lock(p->proc_lock)
+ * - must be called before detach_pid()
+ * - proc_pid_lookup acquires proc_lock, and checks that
+ * the target is not dead by looking at the attach count
+ * of PIDTYPE_PID.
*/
-void proc_flush_task(struct task_struct *task)
+
+struct dentry *proc_pid_unhash(struct task_struct *p)
{
- struct dentry *dentry, *leader, *dir;
- char buf[PROC_NUMBUF];
- struct qstr name;
-
- name.name = buf;
- name.len = snprintf(buf, sizeof(buf), "%d", task->pid);
- dentry = d_hash_and_lookup(proc_mnt->mnt_root, &name);
- if (dentry) {
- shrink_dcache_parent(dentry);
- d_drop(dentry);
- dput(dentry);
- }
+ struct dentry *proc_dentry;
- if (thread_group_leader(task))
- goto out;
+ proc_dentry = p->proc_dentry;
+ if (proc_dentry != NULL) {
- name.name = buf;
- name.len = snprintf(buf, sizeof(buf), "%d", task->tgid);
- leader = d_hash_and_lookup(proc_mnt->mnt_root, &name);
- if (!leader)
- goto out;
+ spin_lock(&dcache_lock);
+ spin_lock(&proc_dentry->d_lock);
+ if (!d_unhashed(proc_dentry)) {
+ dget_locked(proc_dentry);
+ __d_drop(proc_dentry);
+ spin_unlock(&proc_dentry->d_lock);
+ } else {
+ spin_unlock(&proc_dentry->d_lock);
+ proc_dentry = NULL;
+ }
+ spin_unlock(&dcache_lock);
+ }
+ return proc_dentry;
+}
- name.name = "task";
- name.len = strlen(name.name);
- dir = d_hash_and_lookup(leader, &name);
- if (!dir)
- goto out_put_leader;
-
- name.name = buf;
- name.len = snprintf(buf, sizeof(buf), "%d", task->pid);
- dentry = d_hash_and_lookup(dir, &name);
- if (dentry) {
- shrink_dcache_parent(dentry);
- d_drop(dentry);
- dput(dentry);
+/**
+ * proc_pid_flush - recover memory used by stale /proc/@pid/x entries
+ * @proc_dentry: directoy to prune.
+ *
+ * Shrink the /proc directory that was used by the just killed thread.
+ */
+
+void proc_pid_flush(struct dentry *proc_dentry)
+{
+ might_sleep();
+ if(proc_dentry != NULL) {
+ shrink_dcache_parent(proc_dentry);
+ dput(proc_dentry);
}
+}
- dput(dir);
-out_put_leader:
- dput(leader);
-out:
- return;
+#define VXF_FAKE_INIT (VXF_INFO_INIT|VXF_STATE_INIT)
+
+static inline int proc_pid_visible(struct task_struct *task, int pid)
+{
+ if ((pid == 1) &&
+ !vx_flags(VXF_FAKE_INIT, VXF_FAKE_INIT))
+ goto visible;
+ if (vx_check(vx_task_xid(task), VX_WATCH|VX_IDENT))
+ goto visible;
+ return 0;
+visible:
+ return 1;
}
/* SMP-safe */
struct dentry *proc_pid_lookup(struct inode *dir, struct dentry * dentry, struct nameidata *nd)
{
- struct dentry *result = ERR_PTR(-ENOENT);
struct task_struct *task;
struct inode *inode;
struct proc_inode *ei;
unsigned tgid;
+ int died;
if (dentry->d_name.len == 4 && !memcmp(dentry->d_name.name,"self",4)) {
inode = new_inode(dir->i_sb);
if (tgid == ~0U)
goto out;
- rcu_read_lock();
- task = find_proc_task_by_pid(tgid);
+ read_lock(&tasklist_lock);
+ task = find_task_by_pid(tgid);
if (task)
get_task_struct(task);
- rcu_read_unlock();
+ read_unlock(&tasklist_lock);
if (!task)
goto out;
+ /* check for context visibility */
+ if (!proc_pid_visible(task, tgid))
+ goto out_drop_task;
+
inode = proc_pid_make_inode(dir->i_sb, task, PROC_TGID_INO);
if (!inode)
- goto out_put_task;
+ goto out_drop_task;
inode->i_mode = S_IFDIR|S_IRUGO|S_IXUGO;
inode->i_op = &proc_tgid_base_inode_operations;
inode->i_nlink = 4;
#endif
- dentry->d_op = &pid_dentry_operations;
+ dentry->d_op = &pid_base_dentry_operations;
+ died = 0;
d_add(dentry, inode);
- /* Close the race of the process dying before we return the dentry */
- if (pid_revalidate(dentry, NULL))
- result = NULL;
+ spin_lock(&task->proc_lock);
+ task->proc_dentry = dentry;
+ if (!pid_alive(task)) {
+ dentry = proc_pid_unhash(task);
+ died = 1;
+ }
+ spin_unlock(&task->proc_lock);
-out_put_task:
+ put_task_struct(task);
+ if (died) {
+ proc_pid_flush(dentry);
+ goto out;
+ }
+ return NULL;
+out_drop_task:
put_task_struct(task);
out:
- return result;
+ return ERR_PTR(-ENOENT);
}
/* SMP-safe */
static struct dentry *proc_task_lookup(struct inode *dir, struct dentry * dentry, struct nameidata *nd)
{
- struct dentry *result = ERR_PTR(-ENOENT);
struct task_struct *task;
- struct task_struct *leader = get_proc_task(dir);
+ struct task_struct *leader = proc_task(dir);
struct inode *inode;
unsigned tid;
- if (!leader)
- goto out_no_task;
-
tid = name_to_int(dentry);
if (tid == ~0U)
goto out;
if (vx_current_initpid(tid))
goto out;
- rcu_read_lock();
- task = find_proc_task_by_pid(tid);
+ read_lock(&tasklist_lock);
+ task = find_task_by_pid(tid);
if (task)
get_task_struct(task);
- rcu_read_unlock();
+ read_unlock(&tasklist_lock);
if (!task)
goto out;
if (leader->tgid != task->tgid)
goto out_drop_task;
- inode = proc_pid_make_inode(dir->i_sb, task, PROC_TID_INO);
-
+ /* check for context visibility */
+ if (!proc_pid_visible(task, tid))
+ goto out_drop_task;
+ inode = proc_pid_make_inode(dir->i_sb, task, PROC_TID_INO);
if (!inode)
goto out_drop_task;
+
inode->i_mode = S_IFDIR|S_IRUGO|S_IXUGO;
inode->i_op = &proc_tid_base_inode_operations;
inode->i_fop = &proc_tid_base_operations;
inode->i_nlink = 3;
#endif
- dentry->d_op = &pid_dentry_operations;
+ dentry->d_op = &pid_base_dentry_operations;
d_add(dentry, inode);
- /* Close the race of the process dying before we return the dentry */
- if (pid_revalidate(dentry, NULL))
- result = NULL;
+ put_task_struct(task);
+ return NULL;
out_drop_task:
put_task_struct(task);
out:
- put_task_struct(leader);
-out_no_task:
- return result;
+ return ERR_PTR(-ENOENT);
}
+#define PROC_NUMBUF 10
+#define PROC_MAXPIDS 20
+
/*
- * Find the first tgid to return to user space.
- *
- * Usually this is just whatever follows &init_task, but if the users
- * buffer was too small to hold the full list or there was a seek into
- * the middle of the directory we have more work to do.
- *
- * In the case of a short read we start with find_task_by_pid.
- *
- * In the case of a seek we start with &init_task and walk nr
- * threads past it.
+ * Get a few tgid's to return for filldir - we need to hold the
+ * tasklist lock while doing this, and we must release it before
+ * we actually do the filldir itself, so we use a temp buffer..
*/
-static struct task_struct *first_tgid(int tgid, unsigned int nr)
-{
- struct task_struct *pos;
- rcu_read_lock();
- if (tgid && nr) {
- pos = find_proc_task_by_pid(tgid);
- if (pos && thread_group_leader(pos))
- goto found;
+static int get_tgid_list(int index, unsigned long version, unsigned int *tgids)
+{
+ struct task_struct *p;
+ int nr_tgids = 0;
+
+ index--;
+ read_lock(&tasklist_lock);
+ p = NULL;
+ if (version) {
+ p = find_task_by_real_pid(version);
+ if (p && !thread_group_leader(p))
+ p = NULL;
}
- /* If nr exceeds the number of processes get out quickly */
- pos = NULL;
- if (nr && nr >= nr_processes())
- goto done;
- /* If we haven't found our starting place yet start with
- * the init_task and walk nr tasks forward.
- */
- for (pos = next_task(&init_task); nr > 0; --nr) {
- pos = next_task(pos);
- if (pos == &init_task) {
- pos = NULL;
- goto done;
- }
+ if (p)
+ index = 0;
+ else
+ p = next_task(&init_task);
+
+ for ( ; p != &init_task; p = next_task(p)) {
+ int tgid = p->pid;
+
+ if (!pid_alive(p))
+ continue;
+ /* check for context visibility */
+ if (!proc_pid_visible(p, tgid))
+ continue;
+ if (--index >= 0)
+ continue;
+ tgids[nr_tgids] = vx_map_tgid(tgid);
+ nr_tgids++;
+ if (nr_tgids >= PROC_MAXPIDS)
+ break;
}
-found:
- get_task_struct(pos);
-done:
- rcu_read_unlock();
- return pos;
+ read_unlock(&tasklist_lock);
+ return nr_tgids;
}
/*
- * Find the next task in the task list.
- * Return NULL if we loop or there is any error.
- *
- * The reference to the input task_struct is released.
+ * Get a few tid's to return for filldir - we need to hold the
+ * tasklist lock while doing this, and we must release it before
+ * we actually do the filldir itself, so we use a temp buffer..
*/
-static struct task_struct *next_tgid(struct task_struct *start)
-{
- struct task_struct *pos;
- rcu_read_lock();
- pos = start;
- if (pid_alive(start))
- pos = next_task(start);
- if (pid_alive(pos) && (pos != &init_task)) {
- get_task_struct(pos);
- goto done;
- }
- pos = NULL;
-done:
- rcu_read_unlock();
- put_task_struct(start);
- return pos;
+static int get_tid_list(int index, unsigned int *tids, struct inode *dir)
+{
+ struct task_struct *leader_task = proc_task(dir);
+ struct task_struct *task = leader_task;
+ int nr_tids = 0;
+
+ index -= 2;
+ read_lock(&tasklist_lock);
+ /*
+ * The starting point task (leader_task) might be an already
+ * unlinked task, which cannot be used to access the task-list
+ * via next_thread().
+ */
+ if (pid_alive(task)) do {
+ int tid = task->pid;
+
+ /* check for context visibility */
+ if (!proc_pid_visible(task, tid))
+ continue;
+ if (--index >= 0)
+ continue;
+ if (tids != NULL)
+ tids[nr_tids] = vx_map_pid(tid);
+ nr_tids++;
+ if (nr_tids >= PROC_MAXPIDS)
+ break;
+ } while ((task = next_thread(task)) != leader_task);
+ read_unlock(&tasklist_lock);
+ return nr_tids;
}
/* for the /proc/ directory itself, after non-process stuff has been done */
int proc_pid_readdir(struct file * filp, void * dirent, filldir_t filldir)
{
+ unsigned int tgid_array[PROC_MAXPIDS];
char buf[PROC_NUMBUF];
unsigned int nr = filp->f_pos - FIRST_PROCESS_ENTRY;
- struct task_struct *task;
- int tgid;
+ unsigned int nr_tgids, i;
+ int next_tgid;
if (!nr) {
ino_t ino = fake_ino(0,PROC_TGID_INO);
filp->f_pos++;
nr++;
}
- nr -= 1;
/* f_version caches the tgid value that the last readdir call couldn't
* return. lseek aka telldir automagically resets f_version to 0.
*/
- tgid = filp->f_version;
+ next_tgid = filp->f_version;
filp->f_version = 0;
- for (task = first_tgid(tgid, nr);
- task;
- task = next_tgid(task), filp->f_pos++) {
- int len;
- ino_t ino;
- tgid = vx_map_tgid(task->pid);
- if (!proc_pid_visible(task, tgid))
- continue;
-
- len = snprintf(buf, sizeof(buf), "%d", tgid);
- ino = fake_ino(tgid, PROC_TGID_INO);
- if (filldir(dirent, buf, len, filp->f_pos, ino, DT_DIR) < 0) {
- /* returning this tgid failed, save it as the first
- * pid for the next readir call */
- filp->f_version = tgid;
- put_task_struct(task);
+ for (;;) {
+ nr_tgids = get_tgid_list(nr, next_tgid, tgid_array);
+ if (!nr_tgids) {
+ /* no more entries ! */
break;
}
- }
- return 0;
-}
+ next_tgid = 0;
-/*
- * Find the first tid of a thread group to return to user space.
- *
- * Usually this is just the thread group leader, but if the users
- * buffer was too small or there was a seek into the middle of the
- * directory we have more work todo.
- *
- * In the case of a short read we start with find_task_by_pid.
- *
- * In the case of a seek we start with the leader and walk nr
- * threads past it.
- */
-static struct task_struct *first_tid(struct task_struct *leader,
- int tid, int nr)
-{
- struct task_struct *pos;
+ /* do not use the last found pid, reserve it for next_tgid */
+ if (nr_tgids == PROC_MAXPIDS) {
+ nr_tgids--;
+ next_tgid = tgid_array[nr_tgids];
+ }
- rcu_read_lock();
- /* Attempt to start with the pid of a thread */
- if (tid && (nr > 0)) {
- pos = find_proc_task_by_pid(tid);
- if (pos && (pos->group_leader == leader))
- goto found;
- }
+ for (i=0;i<nr_tgids;i++) {
+ int tgid = tgid_array[i];
+ ino_t ino = fake_ino(tgid,PROC_TGID_INO);
+ unsigned long j = PROC_NUMBUF;
- /* If nr exceeds the number of threads there is nothing todo */
- pos = NULL;
- if (nr && nr >= get_nr_threads(leader))
- goto out;
+ do
+ buf[--j] = '0' + (tgid % 10);
+ while ((tgid /= 10) != 0);
- /* If we haven't found our starting place yet start
- * with the leader and walk nr threads forward.
- */
- for (pos = leader; nr > 0; --nr) {
- pos = next_thread(pos);
- if (pos == leader) {
- pos = NULL;
- goto out;
+ if (filldir(dirent, buf+j, PROC_NUMBUF-j, filp->f_pos, ino, DT_DIR) < 0) {
+ /* returning this tgid failed, save it as the first
+ * pid for the next readir call */
+ filp->f_version = tgid_array[i];
+ goto out;
+ }
+ filp->f_pos++;
+ nr++;
}
}
-found:
- get_task_struct(pos);
out:
- rcu_read_unlock();
- return pos;
-}
-
-/*
- * Find the next thread in the thread list.
- * Return NULL if there is an error or no next thread.
- *
- * The reference to the input task_struct is released.
- */
-static struct task_struct *next_tid(struct task_struct *start)
-{
- struct task_struct *pos = NULL;
- rcu_read_lock();
- if (pid_alive(start)) {
- pos = next_thread(start);
- if (thread_group_leader(pos))
- pos = NULL;
- else
- get_task_struct(pos);
- }
- rcu_read_unlock();
- put_task_struct(start);
- return pos;
+ return 0;
}
/* for the /proc/TGID/task/ directories */
static int proc_task_readdir(struct file * filp, void * dirent, filldir_t filldir)
{
+ unsigned int tid_array[PROC_MAXPIDS];
char buf[PROC_NUMBUF];
+ unsigned int nr_tids, i;
struct dentry *dentry = filp->f_dentry;
struct inode *inode = dentry->d_inode;
- struct task_struct *leader = get_proc_task(inode);
- struct task_struct *task;
+ struct task_struct *task = proc_task(inode);
int retval = -ENOENT;
ino_t ino;
- int tid;
unsigned long pos = filp->f_pos; /* avoiding "long long" filp->f_pos */
- if (!leader)
- goto out_no_task;
+ if (!vx_check(vx_task_xid(task), VX_WATCH|VX_IDENT))
+ goto out;
+ if (!pid_alive(task))
+ goto out;
retval = 0;
switch (pos) {
/* fall through */
}
- /* f_version caches the tgid value that the last readdir call couldn't
- * return. lseek aka telldir automagically resets f_version to 0.
- */
- tid = filp->f_version;
- filp->f_version = 0;
- for (task = first_tid(leader, tid, pos - 2);
- task;
- task = next_tid(task), pos++) {
- int len;
- tid = vx_map_pid(task->pid);
- if (!proc_pid_visible(task, tid))
- continue;
+ nr_tids = get_tid_list(pos, tid_array, inode);
+ inode->i_nlink = pos + nr_tids;
+
+ for (i = 0; i < nr_tids; i++) {
+ unsigned long j = PROC_NUMBUF;
+ int tid = tid_array[i];
+
+ ino = fake_ino(tid,PROC_TID_INO);
+
+ do
+ buf[--j] = '0' + (tid % 10);
+ while ((tid /= 10) != 0);
- len = snprintf(buf, sizeof(buf), "%d", tid);
- ino = fake_ino(tid, PROC_TID_INO);
- if (filldir(dirent, buf, len, pos, ino, DT_DIR < 0)) {
- /* returning this tgid failed, save it as the first
- * pid for the next readir call */
- filp->f_version = tid;
- put_task_struct(task);
+ if (filldir(dirent, buf+j, PROC_NUMBUF-j, pos, ino, DT_DIR) < 0)
break;
- }
+ pos++;
}
out:
filp->f_pos = pos;
- put_task_struct(leader);
-out_no_task:
return retval;
}
-
-static int proc_task_getattr(struct vfsmount *mnt, struct dentry *dentry, struct kstat *stat)
-{
- struct inode *inode = dentry->d_inode;
- struct task_struct *p = get_proc_task(inode);
- generic_fillattr(inode, stat);
-
- if (p) {
- rcu_read_lock();
- stat->nlink += get_nr_threads(p);
- rcu_read_unlock();
- put_task_struct(p);
- }
-
- return 0;
-}
git://git.onelab.eu / linux-2.6.git / blobdiff