diff options
| -rw-r--r-- | fs/proc/base.c | 132 |
1 files changed, 114 insertions, 18 deletions
diff --git a/fs/proc/base.c b/fs/proc/base.c index be94ddebb413..0697fd089de8 100644 --- a/fs/proc/base.c +++ b/fs/proc/base.c @@ -1238,7 +1238,10 @@ out: return ~0U; } -static int proc_fd_link(struct inode *inode, struct dentry **dentry, struct vfsmount **mnt) +#define PROC_FDINFO_MAX 64 + +static int proc_fd_info(struct inode *inode, struct dentry **dentry, + struct vfsmount **mnt, char *info) { struct task_struct *task = get_proc_task(inode); struct files_struct *files = NULL; @@ -1257,8 +1260,16 @@ static int proc_fd_link(struct inode *inode, struct dentry **dentry, struct vfsm spin_lock(&files->file_lock); file = fcheck_files(files, fd); if (file) { - *mnt = mntget(file->f_path.mnt); - *dentry = dget(file->f_path.dentry); + if (mnt) + *mnt = mntget(file->f_path.mnt); + if (dentry) + *dentry = dget(file->f_path.dentry); + if (info) + snprintf(info, PROC_FDINFO_MAX, + "pos:\t%lli\n" + "flags:\t0%o\n", + (long long) file->f_pos, + file->f_flags); spin_unlock(&files->file_lock); put_files_struct(files); return 0; @@ -1269,6 +1280,12 @@ static int proc_fd_link(struct inode *inode, struct dentry **dentry, struct vfsm return -ENOENT; } +static int proc_fd_link(struct inode *inode, struct dentry **dentry, + struct vfsmount **mnt) +{ + return proc_fd_info(inode, dentry, mnt, NULL); +} + static int tid_fd_revalidate(struct dentry *dentry, struct nameidata *nd) { struct inode *inode = dentry->d_inode; @@ -1364,7 +1381,9 @@ out_iput: goto out; } -static struct dentry *proc_lookupfd(struct inode * dir, struct dentry * dentry, struct nameidata *nd) +static struct dentry *proc_lookupfd_common(struct inode *dir, + struct dentry *dentry, + instantiate_t instantiate) { struct task_struct *task = get_proc_task(dir); unsigned fd = name_to_int(dentry); @@ -1375,23 +1394,15 @@ static struct dentry *proc_lookupfd(struct inode * dir, struct dentry * dentry, if (fd == ~0U) goto out; - result = proc_fd_instantiate(dir, dentry, task, &fd); + result = instantiate(dir, dentry, task, &fd); out: put_task_struct(task); out_no_task: return result; } -static int proc_fd_fill_cache(struct file *filp, void *dirent, filldir_t filldir, - struct task_struct *task, int fd) -{ - char name[PROC_NUMBUF]; - int len = snprintf(name, sizeof(name), "%d", fd); - return proc_fill_cache(filp, dirent, filldir, name, len, - proc_fd_instantiate, task, &fd); -} - -static int proc_readfd(struct file * filp, void * dirent, filldir_t filldir) +static int proc_readfd_common(struct file * filp, void * dirent, + filldir_t filldir, instantiate_t instantiate) { struct dentry *dentry = filp->f_path.dentry; struct inode *inode = dentry->d_inode; @@ -1427,12 +1438,17 @@ static int proc_readfd(struct file * filp, void * dirent, filldir_t filldir) for (fd = filp->f_pos-2; fd < fdt->max_fds; fd++, filp->f_pos++) { + char name[PROC_NUMBUF]; + int len; if (!fcheck_files(files, fd)) continue; rcu_read_unlock(); - if (proc_fd_fill_cache(filp, dirent, filldir, p, fd) < 0) { + len = snprintf(name, sizeof(name), "%d", fd); + if (proc_fill_cache(filp, dirent, filldir, + name, len, instantiate, + p, &fd) < 0) { rcu_read_lock(); break; } @@ -1447,6 +1463,32 @@ out_no_task: return retval; } +static struct dentry *proc_lookupfd(struct inode *dir, struct dentry *dentry, + struct nameidata *nd) +{ + return proc_lookupfd_common(dir, dentry, proc_fd_instantiate); +} + +static int proc_readfd(struct file *filp, void *dirent, filldir_t filldir) +{ + return proc_readfd_common(filp, dirent, filldir, proc_fd_instantiate); +} + +static ssize_t proc_fdinfo_read(struct file *file, char __user *buf, + size_t len, loff_t *ppos) +{ + char tmp[PROC_FDINFO_MAX]; + int err = proc_fd_info(file->f_path.dentry->d_inode, NULL, NULL, tmp); + if (!err) + err = simple_read_from_buffer(buf, len, ppos, tmp, strlen(tmp)); + return err; +} + +static const struct file_operations proc_fdinfo_file_operations = { + .open = nonseekable_open, + .read = proc_fdinfo_read, +}; + static const struct file_operations proc_fd_operations = { .read = generic_read_dir, .readdir = proc_readfd, @@ -1478,6 +1520,58 @@ static const struct inode_operations proc_fd_inode_operations = { .setattr = proc_setattr, }; +static struct dentry *proc_fdinfo_instantiate(struct inode *dir, + struct dentry *dentry, struct task_struct *task, const void *ptr) +{ + unsigned fd = *(unsigned *)ptr; + struct inode *inode; + struct proc_inode *ei; + struct dentry *error = ERR_PTR(-ENOENT); + + inode = proc_pid_make_inode(dir->i_sb, task); + if (!inode) + goto out; + ei = PROC_I(inode); + ei->fd = fd; + inode->i_mode = S_IFREG | S_IRUSR; + inode->i_fop = &proc_fdinfo_file_operations; + 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)) + error = NULL; + + out: + return error; +} + +static struct dentry *proc_lookupfdinfo(struct inode *dir, + struct dentry *dentry, + struct nameidata *nd) +{ + return proc_lookupfd_common(dir, dentry, proc_fdinfo_instantiate); +} + +static int proc_readfdinfo(struct file *filp, void *dirent, filldir_t filldir) +{ + return proc_readfd_common(filp, dirent, filldir, + proc_fdinfo_instantiate); +} + +static const struct file_operations proc_fdinfo_operations = { + .read = generic_read_dir, + .readdir = proc_readfdinfo, +}; + +/* + * proc directories can do almost nothing.. + */ +static const struct inode_operations proc_fdinfo_inode_operations = { + .lookup = proc_lookupfdinfo, + .setattr = proc_setattr, +}; + + static struct dentry *proc_pident_instantiate(struct inode *dir, struct dentry *dentry, struct task_struct *task, const void *ptr) { @@ -1888,6 +1982,7 @@ static const struct inode_operations proc_task_inode_operations; static const struct pid_entry tgid_base_stuff[] = { DIR("task", S_IRUGO|S_IXUGO, task), DIR("fd", S_IRUSR|S_IXUSR, fd), + DIR("fdinfo", S_IRUSR|S_IXUSR, fdinfo), INF("environ", S_IRUSR, pid_environ), INF("auxv", S_IRUSR, pid_auxv), INF("status", S_IRUGO, pid_status), @@ -2041,7 +2136,7 @@ static struct dentry *proc_pid_instantiate(struct inode *dir, inode->i_op = &proc_tgid_base_inode_operations; inode->i_fop = &proc_tgid_base_operations; inode->i_flags|=S_IMMUTABLE; - inode->i_nlink = 4; + inode->i_nlink = 5; #ifdef CONFIG_SECURITY inode->i_nlink += 1; #endif @@ -2171,6 +2266,7 @@ out_no_task: */ static const struct pid_entry tid_base_stuff[] = { DIR("fd", S_IRUSR|S_IXUSR, fd), + DIR("fdinfo", S_IRUSR|S_IXUSR, fdinfo), INF("environ", S_IRUSR, pid_environ), INF("auxv", S_IRUSR, pid_auxv), INF("status", S_IRUGO, pid_status), @@ -2251,7 +2347,7 @@ static struct dentry *proc_task_instantiate(struct inode *dir, inode->i_op = &proc_tid_base_inode_operations; inode->i_fop = &proc_tid_base_operations; inode->i_flags|=S_IMMUTABLE; - inode->i_nlink = 3; + inode->i_nlink = 4; #ifdef CONFIG_SECURITY inode->i_nlink += 1; #endif |