#include <linux/pid_namespace.h>
#include <linux/fs_struct.h>
#include <linux/slab.h>
+#include <linux/flex_array.h>
#ifdef CONFIG_HARDWALL
#include <asm/hardwall.h>
#endif
NULL, &proc_single_file_operations, \
{ .proc_show = show } )
+static int proc_fd_permission(struct inode *inode, int mask);
+
/*
* Count the number of hardlinks for the pid_entry table, excluding the .
* and .. links.
return result;
}
-static int proc_cwd_link(struct inode *inode, struct path *path)
+static int proc_cwd_link(struct dentry *dentry, struct path *path)
{
- struct task_struct *task = get_proc_task(inode);
+ struct task_struct *task = get_proc_task(dentry->d_inode);
int result = -ENOENT;
if (task) {
return result;
}
-static int proc_root_link(struct inode *inode, struct path *path)
+static int proc_root_link(struct dentry *dentry, struct path *path)
{
- struct task_struct *task = get_proc_task(inode);
+ struct task_struct *task = get_proc_task(dentry->d_inode);
int result = -ENOENT;
if (task) {
return result;
}
-static struct mm_struct *__check_mem_permission(struct task_struct *task)
-{
- struct mm_struct *mm;
-
- mm = get_task_mm(task);
- if (!mm)
- return ERR_PTR(-EINVAL);
-
- /*
- * A task can always look at itself, in case it chooses
- * to use system calls instead of load instructions.
- */
- if (task == current)
- return mm;
-
- /*
- * If current is actively ptrace'ing, and would also be
- * permitted to freshly attach with ptrace now, permit it.
- */
- if (task_is_stopped_or_traced(task)) {
- int match;
- rcu_read_lock();
- match = (ptrace_parent(task) == current);
- rcu_read_unlock();
- if (match && ptrace_may_access(task, PTRACE_MODE_ATTACH))
- return mm;
- }
-
- /*
- * No one else is allowed.
- */
- mmput(mm);
- return ERR_PTR(-EPERM);
-}
-
-/*
- * If current may access user memory in @task return a reference to the
- * corresponding mm, otherwise ERR_PTR.
- */
-static struct mm_struct *check_mem_permission(struct task_struct *task)
-{
- struct mm_struct *mm;
- int err;
-
- /*
- * Avoid racing if task exec's as we might get a new mm but validate
- * against old credentials.
- */
- err = mutex_lock_killable(&task->signal->cred_guard_mutex);
- if (err)
- return ERR_PTR(err);
-
- mm = __check_mem_permission(task);
- mutex_unlock(&task->signal->cred_guard_mutex);
-
- return mm;
-}
-
-struct mm_struct *mm_for_maps(struct task_struct *task)
+static struct mm_struct *mm_access(struct task_struct *task, unsigned int mode)
{
struct mm_struct *mm;
int err;
mm = get_task_mm(task);
if (mm && mm != current->mm &&
- !ptrace_may_access(task, PTRACE_MODE_READ)) {
+ !ptrace_may_access(task, mode)) {
mmput(mm);
mm = ERR_PTR(-EACCES);
}
return mm;
}
+struct mm_struct *mm_for_maps(struct task_struct *task)
+{
+ return mm_access(task, PTRACE_MODE_READ_FSCREDS);
+}
+
static int proc_pid_cmdline(struct task_struct *task, char * buffer)
{
int res = 0;
wchan = get_wchan(task);
if (lookup_symbol_name(wchan, symname) < 0)
- if (!ptrace_may_access(task, PTRACE_MODE_READ))
+ if (!ptrace_may_access(task, PTRACE_MODE_READ_FSCREDS))
return 0;
else
return sprintf(buffer, "%lu", wchan);
int err = mutex_lock_killable(&task->signal->cred_guard_mutex);
if (err)
return err;
- if (!ptrace_may_access(task, PTRACE_MODE_ATTACH)) {
+ if (!ptrace_may_access(task, PTRACE_MODE_ATTACH_FSCREDS)) {
mutex_unlock(&task->signal->cred_guard_mutex);
return -EPERM;
}
*/
task = get_proc_task(inode);
if (task) {
- allowed = ptrace_may_access(task, PTRACE_MODE_READ);
+ allowed = ptrace_may_access(task, PTRACE_MODE_READ_FSCREDS);
put_task_struct(task);
}
return allowed;
if (attr->ia_valid & ATTR_MODE)
return -EPERM;
- error = inode_change_ok(inode, attr);
+ error = setattr_prepare(dentry, attr);
if (error)
return error;
};
static int mem_open(struct inode* inode, struct file* file)
-{
- file->private_data = (void*)((long)current->self_exec_id);
- /* OK to pass negative loff_t, we can catch out-of-range */
- file->f_mode |= FMODE_UNSIGNED_OFFSET;
- return 0;
-}
-
-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_path.dentry->d_inode);
- char *page;
- unsigned long src = *ppos;
- int ret = -ESRCH;
struct mm_struct *mm;
if (!task)
- goto out_no_task;
+ return -ESRCH;
- ret = -ENOMEM;
- page = (char *)__get_free_page(GFP_TEMPORARY);
- if (!page)
- goto out;
+ mm = mm_access(task, PTRACE_MODE_ATTACH | PTRACE_MODE_FSCREDS);
+ put_task_struct(task);
- mm = check_mem_permission(task);
- ret = PTR_ERR(mm);
if (IS_ERR(mm))
- goto out_free;
-
- ret = -EIO;
-
- if (file->private_data != (void*)((long)current->self_exec_id))
- goto out_put;
-
- ret = 0;
-
- while (count > 0) {
- int this_len, retval;
-
- this_len = (count > PAGE_SIZE) ? PAGE_SIZE : count;
- retval = access_remote_vm(mm, src, page, this_len, 0);
- if (!retval) {
- if (!ret)
- ret = -EIO;
- break;
- }
+ return PTR_ERR(mm);
- if (copy_to_user(buf, page, retval)) {
- ret = -EFAULT;
- break;
- }
-
- ret += retval;
- src += retval;
- buf += retval;
- count -= retval;
+ if (mm) {
+ /* ensure this mm_struct can't be freed */
+ atomic_inc(&mm->mm_count);
+ /* but do not pin its memory */
+ mmput(mm);
}
- *ppos = src;
-out_put:
- mmput(mm);
-out_free:
- free_page((unsigned long) page);
-out:
- put_task_struct(task);
-out_no_task:
- return ret;
+ /* OK to pass negative loff_t, we can catch out-of-range */
+ file->f_mode |= FMODE_UNSIGNED_OFFSET;
+ file->private_data = mm;
+
+ return 0;
}
-static ssize_t mem_write(struct file * file, const char __user *buf,
- size_t count, loff_t *ppos)
+static ssize_t mem_rw(struct file *file, char __user *buf,
+ size_t count, loff_t *ppos, int write)
{
- int copied;
+ struct mm_struct *mm = file->private_data;
+ unsigned long addr = *ppos;
+ ssize_t copied;
char *page;
- struct task_struct *task = get_proc_task(file->f_path.dentry->d_inode);
- unsigned long dst = *ppos;
- struct mm_struct *mm;
- copied = -ESRCH;
- if (!task)
- goto out_no_task;
+ if (!mm)
+ return 0;
- copied = -ENOMEM;
page = (char *)__get_free_page(GFP_TEMPORARY);
if (!page)
- goto out_task;
-
- mm = check_mem_permission(task);
- copied = PTR_ERR(mm);
- if (IS_ERR(mm))
- goto out_free;
-
- copied = -EIO;
- if (file->private_data != (void *)((long)current->self_exec_id))
- goto out_mm;
+ return -ENOMEM;
copied = 0;
+ if (!atomic_inc_not_zero(&mm->mm_users))
+ goto free;
+
while (count > 0) {
- int this_len, retval;
+ int this_len = min_t(int, count, PAGE_SIZE);
- this_len = (count > PAGE_SIZE) ? PAGE_SIZE : count;
- if (copy_from_user(page, buf, this_len)) {
+ if (write && copy_from_user(page, buf, this_len)) {
copied = -EFAULT;
break;
}
- retval = access_remote_vm(mm, dst, page, this_len, 1);
- if (!retval) {
+
+ this_len = access_remote_vm(mm, addr, page, this_len, write);
+ if (!this_len) {
if (!copied)
copied = -EIO;
break;
}
- copied += retval;
- buf += retval;
- dst += retval;
- count -= retval;
+
+ if (!write && copy_to_user(buf, page, this_len)) {
+ copied = -EFAULT;
+ break;
+ }
+
+ buf += this_len;
+ addr += this_len;
+ copied += this_len;
+ count -= this_len;
}
- *ppos = dst;
+ *ppos = addr;
-out_mm:
mmput(mm);
-out_free:
+free:
free_page((unsigned long) page);
-out_task:
- put_task_struct(task);
-out_no_task:
return copied;
}
+static ssize_t mem_read(struct file *file, char __user *buf,
+ size_t count, loff_t *ppos)
+{
+ return mem_rw(file, buf, count, ppos, 0);
+}
+
+static ssize_t mem_write(struct file *file, const char __user *buf,
+ size_t count, loff_t *ppos)
+{
+ return mem_rw(file, (char __user*)buf, count, ppos, 1);
+}
+
loff_t mem_lseek(struct file *file, loff_t offset, int orig)
{
switch (orig) {
return file->f_pos;
}
+static int mem_release(struct inode *inode, struct file *file)
+{
+ struct mm_struct *mm = file->private_data;
+ if (mm)
+ mmdrop(mm);
+ return 0;
+}
+
static const struct file_operations proc_mem_operations = {
.llseek = mem_lseek,
.read = mem_read,
.write = mem_write,
.open = mem_open,
+ .release = mem_release,
};
static ssize_t environ_read(struct file *file, char __user *buf,
mm = mm_for_maps(task);
ret = PTR_ERR(mm);
- if (!mm || IS_ERR(mm))
+ /* Ensure the process spawned far enough to have an environment. */
+ if (!mm || IS_ERR(mm) || !mm->env_end)
goto out_free;
ret = 0;
.release = single_release,
};
-static int proc_exe_link(struct inode *inode, struct path *exe_path)
+static int proc_exe_link(struct dentry *dentry, struct path *exe_path)
{
struct task_struct *task;
struct mm_struct *mm;
struct file *exe_file;
- task = get_proc_task(inode);
+ task = get_proc_task(dentry->d_inode);
if (!task)
return -ENOENT;
mm = get_task_mm(task);
if (!proc_fd_access_allowed(inode))
goto out;
- error = PROC_I(inode)->op.proc_get_link(inode, &nd->path);
+ error = PROC_I(inode)->op.proc_get_link(dentry, &nd->path);
out:
return ERR_PTR(error);
}
if (!proc_fd_access_allowed(inode))
goto out;
- error = PROC_I(inode)->op.proc_get_link(inode, &path);
+ error = PROC_I(inode)->op.proc_get_link(dentry, &path);
if (error)
goto out;
fdt = files_fdtable(files);
f_flags = file->f_flags & ~O_CLOEXEC;
- if (FD_ISSET(fd, fdt->close_on_exec))
+ if (close_on_exec(fd, fdt))
f_flags |= O_CLOEXEC;
if (path) {
return -ENOENT;
}
-static int proc_fd_link(struct inode *inode, struct path *path)
+static int proc_fd_link(struct dentry *dentry, struct path *path)
{
- return proc_fd_info(inode, path, NULL);
+ return proc_fd_info(dentry->d_inode, path, NULL);
}
static int tid_fd_revalidate(struct dentry *dentry, struct nameidata *nd)
.llseek = default_llseek,
};
+#ifdef CONFIG_CHECKPOINT_RESTORE
+
+/*
+ * dname_to_vma_addr - maps a dentry name into two unsigned longs
+ * which represent vma start and end addresses.
+ */
+static int dname_to_vma_addr(struct dentry *dentry,
+ unsigned long *start, unsigned long *end)
+{
+ if (sscanf(dentry->d_name.name, "%lx-%lx", start, end) != 2)
+ return -EINVAL;
+
+ return 0;
+}
+
+static int map_files_d_revalidate(struct dentry *dentry, struct nameidata *nd)
+{
+ unsigned long vm_start, vm_end;
+ bool exact_vma_exists = false;
+ struct mm_struct *mm = NULL;
+ struct task_struct *task;
+ const struct cred *cred;
+ struct inode *inode;
+ int status = 0;
+
+ if (nd && nd->flags & LOOKUP_RCU)
+ return -ECHILD;
+
+ if (!capable(CAP_SYS_ADMIN)) {
+ status = -EACCES;
+ goto out_notask;
+ }
+
+ inode = dentry->d_inode;
+ task = get_proc_task(inode);
+ if (!task)
+ goto out_notask;
+
+ if (!ptrace_may_access(task, PTRACE_MODE_READ))
+ goto out;
+
+ mm = get_task_mm(task);
+ if (!mm)
+ goto out;
+
+ if (!dname_to_vma_addr(dentry, &vm_start, &vm_end)) {
+ down_read(&mm->mmap_sem);
+ exact_vma_exists = !!find_exact_vma(mm, vm_start, vm_end);
+ up_read(&mm->mmap_sem);
+ }
+
+ mmput(mm);
+
+ if (exact_vma_exists) {
+ if (task_dumpable(task)) {
+ rcu_read_lock();
+ cred = __task_cred(task);
+ inode->i_uid = cred->euid;
+ inode->i_gid = cred->egid;
+ rcu_read_unlock();
+ } else {
+ inode->i_uid = 0;
+ inode->i_gid = 0;
+ }
+ security_task_to_inode(task, inode);
+ status = 1;
+ }
+
+out:
+ put_task_struct(task);
+
+out_notask:
+ if (status <= 0)
+ d_drop(dentry);
+
+ return status;
+}
+
+static const struct dentry_operations tid_map_files_dentry_operations = {
+ .d_revalidate = map_files_d_revalidate,
+ .d_delete = pid_delete_dentry,
+};
+
+static int proc_map_files_get_link(struct dentry *dentry, struct path *path)
+{
+ unsigned long vm_start, vm_end;
+ struct vm_area_struct *vma;
+ struct task_struct *task;
+ struct mm_struct *mm;
+ int rc;
+
+ rc = -ENOENT;
+ task = get_proc_task(dentry->d_inode);
+ if (!task)
+ goto out;
+
+ mm = get_task_mm(task);
+ put_task_struct(task);
+ if (!mm)
+ goto out;
+
+ rc = dname_to_vma_addr(dentry, &vm_start, &vm_end);
+ if (rc)
+ goto out_mmput;
+
+ down_read(&mm->mmap_sem);
+ vma = find_exact_vma(mm, vm_start, vm_end);
+ if (vma && vma->vm_file) {
+ *path = vma->vm_file->f_path;
+ path_get(path);
+ rc = 0;
+ }
+ up_read(&mm->mmap_sem);
+
+out_mmput:
+ mmput(mm);
+out:
+ return rc;
+}
+
+struct map_files_info {
+ struct file *file;
+ unsigned long len;
+ unsigned char name[4*sizeof(long)+2]; /* max: %lx-%lx\0 */
+};
+
+static struct dentry *
+proc_map_files_instantiate(struct inode *dir, struct dentry *dentry,
+ struct task_struct *task, const void *ptr)
+{
+ const struct file *file = ptr;
+ struct proc_inode *ei;
+ struct inode *inode;
+
+ if (!file)
+ return ERR_PTR(-ENOENT);
+
+ inode = proc_pid_make_inode(dir->i_sb, task);
+ if (!inode)
+ return ERR_PTR(-ENOENT);
+
+ ei = PROC_I(inode);
+ ei->op.proc_get_link = proc_map_files_get_link;
+
+ inode->i_op = &proc_pid_link_inode_operations;
+ inode->i_size = 64;
+ inode->i_mode = S_IFLNK;
+
+ if (file->f_mode & FMODE_READ)
+ inode->i_mode |= S_IRUSR;
+ if (file->f_mode & FMODE_WRITE)
+ inode->i_mode |= S_IWUSR;
+
+ d_set_d_op(dentry, &tid_map_files_dentry_operations);
+ d_add(dentry, inode);
+
+ return NULL;
+}
+
+static struct dentry *proc_map_files_lookup(struct inode *dir,
+ struct dentry *dentry, struct nameidata *nd)
+{
+ unsigned long vm_start, vm_end;
+ struct vm_area_struct *vma;
+ struct task_struct *task;
+ struct dentry *result;
+ struct mm_struct *mm;
+
+ result = ERR_PTR(-EACCES);
+ if (!capable(CAP_SYS_ADMIN))
+ goto out;
+
+ result = ERR_PTR(-ENOENT);
+ task = get_proc_task(dir);
+ if (!task)
+ goto out;
+
+ result = ERR_PTR(-EACCES);
+ if (lock_trace(task))
+ goto out_put_task;
+
+ result = ERR_PTR(-ENOENT);
+ if (dname_to_vma_addr(dentry, &vm_start, &vm_end))
+ goto out_unlock;
+
+ mm = get_task_mm(task);
+ if (!mm)
+ goto out_unlock;
+
+ down_read(&mm->mmap_sem);
+ vma = find_exact_vma(mm, vm_start, vm_end);
+ if (!vma)
+ goto out_no_vma;
+
+ result = proc_map_files_instantiate(dir, dentry, task, vma->vm_file);
+
+out_no_vma:
+ up_read(&mm->mmap_sem);
+ mmput(mm);
+out_unlock:
+ unlock_trace(task);
+out_put_task:
+ put_task_struct(task);
+out:
+ return result;
+}
+
+static const struct inode_operations proc_map_files_inode_operations = {
+ .lookup = proc_map_files_lookup,
+ .permission = proc_fd_permission,
+ .setattr = proc_setattr,
+};
+
+static int
+proc_map_files_readdir(struct file *filp, void *dirent, filldir_t filldir)
+{
+ struct dentry *dentry = filp->f_path.dentry;
+ struct inode *inode = dentry->d_inode;
+ struct vm_area_struct *vma;
+ struct task_struct *task;
+ struct mm_struct *mm;
+ ino_t ino;
+ int ret;
+
+ ret = -EACCES;
+ if (!capable(CAP_SYS_ADMIN))
+ goto out;
+
+ ret = -ENOENT;
+ task = get_proc_task(inode);
+ if (!task)
+ goto out;
+
+ ret = -EACCES;
+ if (lock_trace(task))
+ goto out_put_task;
+
+ ret = 0;
+ switch (filp->f_pos) {
+ case 0:
+ ino = inode->i_ino;
+ if (filldir(dirent, ".", 1, 0, ino, DT_DIR) < 0)
+ goto out_unlock;
+ filp->f_pos++;
+ case 1:
+ ino = parent_ino(dentry);
+ if (filldir(dirent, "..", 2, 1, ino, DT_DIR) < 0)
+ goto out_unlock;
+ filp->f_pos++;
+ default:
+ {
+ unsigned long nr_files, pos, i;
+ struct flex_array *fa = NULL;
+ struct map_files_info info;
+ struct map_files_info *p;
+
+ mm = get_task_mm(task);
+ if (!mm)
+ goto out_unlock;
+ down_read(&mm->mmap_sem);
+
+ nr_files = 0;
+
+ /*
+ * We need two passes here:
+ *
+ * 1) Collect vmas of mapped files with mmap_sem taken
+ * 2) Release mmap_sem and instantiate entries
+ *
+ * otherwise we get lockdep complained, since filldir()
+ * routine might require mmap_sem taken in might_fault().
+ */
+
+ for (vma = mm->mmap, pos = 2; vma; vma = vma->vm_next) {
+ if (vma->vm_file && ++pos > filp->f_pos)
+ nr_files++;
+ }
+
+ if (nr_files) {
+ fa = flex_array_alloc(sizeof(info), nr_files,
+ GFP_KERNEL);
+ if (!fa || flex_array_prealloc(fa, 0, nr_files,
+ GFP_KERNEL)) {
+ ret = -ENOMEM;
+ if (fa)
+ flex_array_free(fa);
+ up_read(&mm->mmap_sem);
+ mmput(mm);
+ goto out_unlock;
+ }
+ for (i = 0, vma = mm->mmap, pos = 2; vma;
+ vma = vma->vm_next) {
+ if (!vma->vm_file)
+ continue;
+ if (++pos <= filp->f_pos)
+ continue;
+
+ get_file(vma->vm_file);
+ info.file = vma->vm_file;
+ info.len = snprintf(info.name,
+ sizeof(info.name), "%lx-%lx",
+ vma->vm_start, vma->vm_end);
+ if (flex_array_put(fa, i++, &info, GFP_KERNEL))
+ BUG();
+ }
+ }
+ up_read(&mm->mmap_sem);
+
+ for (i = 0; i < nr_files; i++) {
+ p = flex_array_get(fa, i);
+ ret = proc_fill_cache(filp, dirent, filldir,
+ p->name, p->len,
+ proc_map_files_instantiate,
+ task, p->file);
+ if (ret)
+ break;
+ filp->f_pos++;
+ fput(p->file);
+ }
+ for (; i < nr_files; i++) {
+ /*
+ * In case of error don't forget
+ * to put rest of file refs.
+ */
+ p = flex_array_get(fa, i);
+ fput(p->file);
+ }
+ if (fa)
+ flex_array_free(fa);
+ mmput(mm);
+ }
+ }
+
+out_unlock:
+ unlock_trace(task);
+out_put_task:
+ put_task_struct(task);
+out:
+ return ret;
+}
+
+static const struct file_operations proc_map_files_operations = {
+ .read = generic_read_dir,
+ .readdir = proc_map_files_readdir,
+ .llseek = default_llseek,
+};
+
+#endif /* CONFIG_CHECKPOINT_RESTORE */
+
/*
* /proc/pid/fd needs a special permission handler so that a process can still
* access /proc/self/fd after it has executed a setuid().
if (result)
return result;
- if (!ptrace_may_access(task, PTRACE_MODE_READ)) {
+ if (!ptrace_may_access(task, PTRACE_MODE_READ_FSCREDS)) {
result = -EACCES;
goto out_unlock;
}
static const struct pid_entry tgid_base_stuff[] = {
DIR("task", S_IRUGO|S_IXUGO, proc_task_inode_operations, proc_task_operations),
DIR("fd", S_IRUSR|S_IXUSR, proc_fd_inode_operations, proc_fd_operations),
+#ifdef CONFIG_CHECKPOINT_RESTORE
+ DIR("map_files", S_IRUSR|S_IXUSR, proc_map_files_inode_operations, proc_map_files_operations),
+#endif
DIR("fdinfo", S_IRUSR|S_IXUSR, proc_fdinfo_inode_operations, proc_fdinfo_operations),
DIR("ns", S_IRUSR|S_IXUGO, proc_ns_dir_inode_operations, proc_ns_dir_operations),
#ifdef CONFIG_NET
ONE("stat", S_IRUGO, proc_tgid_stat),
ONE("statm", S_IRUGO, proc_pid_statm),
REG("maps", S_IRUGO, proc_maps_operations),
+ REG("arm_maps", S_IRUGO, proc_armv7_maps_operations),
#ifdef CONFIG_NUMA
REG("numa_maps", S_IRUGO, proc_numa_maps_operations),
#endif
ONE("stat", S_IRUGO, proc_tid_stat),
ONE("statm", S_IRUGO, proc_pid_statm),
REG("maps", S_IRUGO, proc_maps_operations),
+ REG("arm_maps", S_IRUGO, proc_armv7_maps_operations),
#ifdef CONFIG_NUMA
REG("numa_maps", S_IRUGO, proc_numa_maps_operations),
#endif