unsigned long arg_start, arg_end, env_start, env_end;
unsigned long len1, len2, len;
unsigned long p;
+ char __user *buf0 = buf;
char c;
- ssize_t rv;
+ int rv;
BUG_ON(*pos < 0);
goto out_mmput;
}
- down_read(&mm->mmap_sem);
+ spin_lock(&mm->arg_lock);
arg_start = mm->arg_start;
arg_end = mm->arg_end;
env_start = mm->env_start;
env_end = mm->env_end;
- up_read(&mm->mmap_sem);
+ spin_unlock(&mm->arg_lock);
BUG_ON(arg_start > arg_end);
BUG_ON(env_start > env_end);
len2 = env_end - env_start;
/* Empty ARGV. */
- if (len1 == 0) {
- rv = 0;
- goto out_free_page;
- }
+ if (len1 == 0)
+ goto end;
+
/*
* Inherently racy -- command line shares address space
* with code and data.
*/
- rv = access_remote_vm(mm, arg_end - 1, &c, 1, FOLL_ANON);
- if (rv <= 0)
- goto out_free_page;
-
- rv = 0;
+ if (access_remote_vm(mm, arg_end - 1, &c, 1, FOLL_ANON) != 1)
+ goto end;
if (c == '\0') {
/* Command line (set of strings) occupies whole ARGV. */
if (len1 <= *pos)
- goto out_free_page;
+ goto end;
p = arg_start + *pos;
len = len1 - *pos;
while (count > 0 && len > 0) {
- unsigned int _count;
- int nr_read;
-
- _count = min3(count, len, PAGE_SIZE);
- nr_read = access_remote_vm(mm, p, page, _count, FOLL_ANON);
- if (nr_read < 0)
- rv = nr_read;
- if (nr_read <= 0)
- goto out_free_page;
+ unsigned int nr_read;
+
+ nr_read = min3(count, len, PAGE_SIZE);
+ nr_read = access_remote_vm(mm, p, page, nr_read, FOLL_ANON);
+ if (nr_read == 0)
+ goto end;
if (copy_to_user(buf, page, nr_read)) {
rv = -EFAULT;
len -= nr_read;
buf += nr_read;
count -= nr_read;
- rv += nr_read;
}
} else {
/*
p = cmdline[i].p + pos1;
len = cmdline[i].len - pos1;
while (count > 0 && len > 0) {
- unsigned int _count, l;
- int nr_read;
- bool final;
-
- _count = min3(count, len, PAGE_SIZE);
- nr_read = access_remote_vm(mm, p, page, _count, FOLL_ANON);
- if (nr_read < 0)
- rv = nr_read;
- if (nr_read <= 0)
- goto out_free_page;
+ unsigned int nr_read, nr_write;
+
+ nr_read = min3(count, len, PAGE_SIZE);
+ nr_read = access_remote_vm(mm, p, page, nr_read, FOLL_ANON);
+ if (nr_read == 0)
+ goto end;
/*
* Command line can be shorter than whole ARGV
* even if last "marker" byte says it is not.
*/
- final = false;
- l = strnlen(page, nr_read);
- if (l < nr_read) {
- nr_read = l;
- final = true;
- }
+ nr_write = strnlen(page, nr_read);
- if (copy_to_user(buf, page, nr_read)) {
+ if (copy_to_user(buf, page, nr_write)) {
rv = -EFAULT;
goto out_free_page;
}
- p += nr_read;
- len -= nr_read;
- buf += nr_read;
- count -= nr_read;
- rv += nr_read;
+ p += nr_write;
+ len -= nr_write;
+ buf += nr_write;
+ count -= nr_write;
- if (final)
- goto out_free_page;
+ if (nr_write < nr_read)
+ goto end;
}
/* Only first chunk can be read partially. */
}
}
+end:
+ *pos += buf - buf0;
+ rv = buf - buf0;
out_free_page:
free_page((unsigned long)page);
out_mmput:
mmput(mm);
- if (rv > 0)
- *pos += rv;
return rv;
}
if (!mmget_not_zero(mm))
goto free;
- down_read(&mm->mmap_sem);
+ spin_lock(&mm->arg_lock);
env_start = mm->env_start;
env_end = mm->env_end;
- up_read(&mm->mmap_sem);
+ spin_unlock(&mm->arg_lock);
while (count > 0) {
size_t this_len, max_len;
if (!p)
return -ESRCH;
- task_lock(p);
- seq_printf(m, "%s\n", p->comm);
- task_unlock(p);
+ proc_task_name(m, p, false);
+ seq_putc(m, '\n');
put_task_struct(p);
/* dentry stuff */
/*
- * Exceptional case: normally we are not allowed to unhash a busy
- * directory. In this case, however, we can do it - no aliasing problems
- * due to the way we treat inodes.
- *
+ * Set <pid>/... inode ownership (can change due to setuid(), etc.)
+ */
+void pid_update_inode(struct task_struct *task, struct inode *inode)
+{
+ task_dump_owner(task, inode->i_mode, &inode->i_uid, &inode->i_gid);
+
+ inode->i_mode &= ~(S_ISUID | S_ISGID);
+ security_task_to_inode(task, inode);
+}
+
+/*
* Rewrite the inode's ownerships here because the owning task may have
* performed a setuid(), etc.
*
*/
-int pid_revalidate(struct dentry *dentry, unsigned int flags)
+static int pid_revalidate(struct dentry *dentry, unsigned int flags)
{
struct inode *inode;
struct task_struct *task;
task = get_proc_task(inode);
if (task) {
- task_dump_owner(task, inode->i_mode, &inode->i_uid, &inode->i_gid);
-
- inode->i_mode &= ~(S_ISUID | S_ISGID);
- security_task_to_inode(task, inode);
+ pid_update_inode(task, inode);
put_task_struct(task);
return 1;
}
struct dentry *child, *dir = file->f_path.dentry;
struct qstr qname = QSTR_INIT(name, len);
struct inode *inode;
- unsigned type;
- ino_t ino;
+ unsigned type = DT_UNKNOWN;
+ ino_t ino = 1;
child = d_hash_and_lookup(dir, &qname);
if (!child) {
if (IS_ERR(child))
goto end_instantiate;
if (d_in_lookup(child)) {
- int err = instantiate(d_inode(dir), child, task, ptr);
+ struct dentry *res;
+ res = instantiate(child, task, ptr);
d_lookup_done(child);
- if (err < 0) {
- dput(child);
+ if (IS_ERR(res))
goto end_instantiate;
+ if (unlikely(res)) {
+ dput(child);
+ child = res;
}
}
}
inode = d_inode(child);
ino = inode->i_ino;
type = inode->i_mode >> 12;
+end_instantiate:
dput(child);
return dir_emit(ctx, name, len, ino, type);
-
-end_instantiate:
- return dir_emit(ctx, name, len, 1, DT_UNKNOWN);
}
/*
.setattr = proc_setattr,
};
-static int
-proc_map_files_instantiate(struct inode *dir, struct dentry *dentry,
+static struct dentry *
+proc_map_files_instantiate(struct dentry *dentry,
struct task_struct *task, const void *ptr)
{
fmode_t mode = (fmode_t)(unsigned long)ptr;
struct proc_inode *ei;
struct inode *inode;
- inode = proc_pid_make_inode(dir->i_sb, task, S_IFLNK |
+ inode = proc_pid_make_inode(dentry->d_sb, task, S_IFLNK |
((mode & FMODE_READ ) ? S_IRUSR : 0) |
((mode & FMODE_WRITE) ? S_IWUSR : 0));
if (!inode)
- return -ENOENT;
+ return ERR_PTR(-ENOENT);
ei = PROC_I(inode);
ei->op.proc_get_link = map_files_get_link;
inode->i_size = 64;
d_set_d_op(dentry, &tid_map_files_dentry_operations);
- d_add(dentry, inode);
-
- return 0;
+ return d_splice_alias(inode, dentry);
}
static struct dentry *proc_map_files_lookup(struct inode *dir,
unsigned long vm_start, vm_end;
struct vm_area_struct *vma;
struct task_struct *task;
- int result;
+ struct dentry *result;
struct mm_struct *mm;
- result = -ENOENT;
+ result = ERR_PTR(-ENOENT);
task = get_proc_task(dir);
if (!task)
goto out;
- result = -EACCES;
+ result = ERR_PTR(-EACCES);
if (!ptrace_may_access(task, PTRACE_MODE_READ_FSCREDS))
goto out_put_task;
- result = -ENOENT;
+ result = ERR_PTR(-ENOENT);
if (dname_to_vma_addr(dentry, &vm_start, &vm_end))
goto out_put_task;
goto out_no_vma;
if (vma->vm_file)
- result = proc_map_files_instantiate(dir, dentry, task,
+ result = proc_map_files_instantiate(dentry, task,
(void *)(unsigned long)vma->vm_file->f_mode);
out_no_vma:
out_put_task:
put_task_struct(task);
out:
- return ERR_PTR(result);
+ return result;
}
static const struct inode_operations proc_map_files_inode_operations = {
.release = single_release,
};
-static int proc_pident_instantiate(struct inode *dir,
- struct dentry *dentry, struct task_struct *task, const void *ptr)
+static struct dentry *proc_pident_instantiate(struct dentry *dentry,
+ struct task_struct *task, const void *ptr)
{
const struct pid_entry *p = ptr;
struct inode *inode;
struct proc_inode *ei;
- inode = proc_pid_make_inode(dir->i_sb, task, p->mode);
+ inode = proc_pid_make_inode(dentry->d_sb, task, p->mode);
if (!inode)
- goto out;
+ return ERR_PTR(-ENOENT);
ei = PROC_I(inode);
if (S_ISDIR(inode->i_mode))
if (p->fop)
inode->i_fop = p->fop;
ei->op = p->op;
+ pid_update_inode(task, inode);
d_set_d_op(dentry, &pid_dentry_operations);
- d_add(dentry, inode);
- /* Close the race of the process dying before we return the dentry */
- if (pid_revalidate(dentry, 0))
- return 0;
-out:
- return -ENOENT;
+ return d_splice_alias(inode, dentry);
}
static struct dentry *proc_pident_lookup(struct inode *dir,
const struct pid_entry *ents,
unsigned int nents)
{
- int error;
struct task_struct *task = get_proc_task(dir);
const struct pid_entry *p, *last;
-
- error = -ENOENT;
+ struct dentry *res = ERR_PTR(-ENOENT);
if (!task)
goto out_no_task;
if (p >= last)
goto out;
- error = proc_pident_instantiate(dir, dentry, task, p);
+ res = proc_pident_instantiate(dentry, task, p);
out:
put_task_struct(task);
out_no_task:
- return ERR_PTR(error);
+ return res;
}
static int proc_pident_readdir(struct file *file, struct dir_context *ctx,
}
}
-static int proc_pid_instantiate(struct inode *dir,
- struct dentry * dentry,
+static struct dentry *proc_pid_instantiate(struct dentry * dentry,
struct task_struct *task, const void *ptr)
{
struct inode *inode;
- inode = proc_pid_make_inode(dir->i_sb, task, S_IFDIR | S_IRUGO | S_IXUGO);
+ inode = proc_pid_make_inode(dentry->d_sb, task, S_IFDIR | S_IRUGO | S_IXUGO);
if (!inode)
- goto out;
+ return ERR_PTR(-ENOENT);
inode->i_op = &proc_tgid_base_inode_operations;
inode->i_fop = &proc_tgid_base_operations;
inode->i_flags|=S_IMMUTABLE;
set_nlink(inode, nlink_tgid);
+ pid_update_inode(task, inode);
d_set_d_op(dentry, &pid_dentry_operations);
-
- d_add(dentry, inode);
- /* Close the race of the process dying before we return the dentry */
- if (pid_revalidate(dentry, 0))
- return 0;
-out:
- return -ENOENT;
+ return d_splice_alias(inode, dentry);
}
struct dentry *proc_pid_lookup(struct inode *dir, struct dentry * dentry, unsigned int flags)
{
- int result = -ENOENT;
struct task_struct *task;
unsigned tgid;
struct pid_namespace *ns;
+ struct dentry *result = ERR_PTR(-ENOENT);
tgid = name_to_int(&dentry->d_name);
if (tgid == ~0U)
if (!task)
goto out;
- result = proc_pid_instantiate(dir, dentry, task, NULL);
+ result = proc_pid_instantiate(dentry, task, NULL);
put_task_struct(task);
out:
- return ERR_PTR(result);
+ return result;
}
/*
.setattr = proc_setattr,
};
-static int proc_task_instantiate(struct inode *dir,
- struct dentry *dentry, struct task_struct *task, const void *ptr)
+static struct dentry *proc_task_instantiate(struct dentry *dentry,
+ struct task_struct *task, const void *ptr)
{
struct inode *inode;
- inode = proc_pid_make_inode(dir->i_sb, task, S_IFDIR | S_IRUGO | S_IXUGO);
-
+ inode = proc_pid_make_inode(dentry->d_sb, task, S_IFDIR | S_IRUGO | S_IXUGO);
if (!inode)
- goto out;
+ return ERR_PTR(-ENOENT);
+
inode->i_op = &proc_tid_base_inode_operations;
inode->i_fop = &proc_tid_base_operations;
- inode->i_flags|=S_IMMUTABLE;
+ inode->i_flags |= S_IMMUTABLE;
set_nlink(inode, nlink_tid);
+ pid_update_inode(task, inode);
d_set_d_op(dentry, &pid_dentry_operations);
-
- d_add(dentry, inode);
- /* Close the race of the process dying before we return the dentry */
- if (pid_revalidate(dentry, 0))
- return 0;
-out:
- return -ENOENT;
+ return d_splice_alias(inode, dentry);
}
static struct dentry *proc_task_lookup(struct inode *dir, struct dentry * dentry, unsigned int flags)
{
- int result = -ENOENT;
struct task_struct *task;
struct task_struct *leader = get_proc_task(dir);
unsigned tid;
struct pid_namespace *ns;
+ struct dentry *result = ERR_PTR(-ENOENT);
if (!leader)
goto out_no_task;
if (!same_thread_group(leader, task))
goto out_drop_task;
- result = proc_task_instantiate(dir, dentry, task, NULL);
+ result = proc_task_instantiate(dentry, task, NULL);
out_drop_task:
put_task_struct(task);
out:
put_task_struct(leader);
out_no_task:
- return ERR_PTR(result);
+ return result;
}
/*
projects / mirror_ubuntu-eoan-kernel.git / blobdiff