Release 4.12 fs/readdir.c

Directory: fs
/*
 *  linux/fs/readdir.c
 *
 *  Copyright (C) 1995  Linus Torvalds
 */

#include <linux/stddef.h>
#include <linux/kernel.h>
#include <linux/export.h>
#include <linux/time.h>
#include <linux/mm.h>
#include <linux/errno.h>
#include <linux/stat.h>
#include <linux/file.h>
#include <linux/fs.h>
#include <linux/fsnotify.h>
#include <linux/dirent.h>
#include <linux/security.h>
#include <linux/syscalls.h>
#include <linux/unistd.h>
#include <linux/compat.h>

#include <linux/uaccess.h>



int iterate_dir(struct file *file, struct dir_context *ctx)
{
	struct inode *inode = file_inode(file);
	bool shared = false;
	int res = -ENOTDIR;
	if (file->f_op->iterate_shared)
		shared = true;
	else if (!file->f_op->iterate)
		goto out;

	res = security_file_permission(file, MAY_READ);
	if (res)
		goto out;

	if (shared) {
		inode_lock_shared(inode);
	} else {
		res = down_write_killable(&inode->i_rwsem);
		if (res)
			goto out;
	}

	res = -ENOENT;
	if (!IS_DEADDIR(inode)) {
		ctx->pos = file->f_pos;
		if (shared)
			res = file->f_op->iterate_shared(file, ctx);
		else
			res = file->f_op->iterate(file, ctx);
		file->f_pos = ctx->pos;
		fsnotify_access(file);
		file_accessed(file);
	}
	if (shared)
		inode_unlock_shared(inode);
	else
		inode_unlock(inode);
out:
	return res;
}
Contributors
Person Tokens Prop Commits CommitProp
Al Viro 114 57.00% 7 46.67%
Linus Torvalds (pre-git) 62 31.00% 3 20.00%
Stephen D. Smalley 11 5.50% 1 6.67%
Heinrich Schuchardt 5 2.50% 1 6.67%
Greg Kroah-Hartman 5 2.50% 2 13.33%
Andrew Morton 3 1.50% 1 6.67%
Total 200 100.00% 15 100.00%


EXPORT_SYMBOL(iterate_dir);

/*
 * Traditional linux readdir() handling..
 *
 * "count=1" is a special case, meaning that the buffer is one
 * dirent-structure in size and that the code can't handle more
 * anyway. Thus the special "fillonedir()" function for that
 * case (the low-level handlers don't need to care about this).
 */

#ifdef __ARCH_WANT_OLD_READDIR


struct old_linux_dirent {
	
unsigned long	d_ino;
	
unsigned long	d_offset;
	
unsigned short	d_namlen;
	
char		d_name[1];
};


struct readdir_callback {
	
struct dir_context ctx;
	
struct old_linux_dirent __user * dirent;
	
int result;
};



static int fillonedir(struct dir_context *ctx, const char *name, int namlen,
		      loff_t offset, u64 ino, unsigned int d_type)
{
	struct readdir_callback *buf =
		container_of(ctx, struct readdir_callback, ctx);
	struct old_linux_dirent __user * dirent;
	unsigned long d_ino;

	if (buf->result)
		return -EINVAL;
	d_ino = ino;
	if (sizeof(d_ino) < sizeof(ino) && d_ino != ino) {
		buf->result = -EOVERFLOW;
		return -EOVERFLOW;
	}
	buf->result++;
	dirent = buf->dirent;
	if (!access_ok(VERIFY_WRITE, dirent,
			(unsigned long)(dirent->d_name + namlen + 1) -
				(unsigned long)dirent))
		goto efault;
	if (	__put_user(d_ino, &dirent->d_ino) ||
		__put_user(offset, &dirent->d_offset) ||
		__put_user(namlen, &dirent->d_namlen) ||
		__copy_to_user(dirent->d_name, name, namlen) ||
		__put_user(0, dirent->d_name + namlen))
		goto efault;
	return 0;
efault:
	buf->result = -EFAULT;
	return -EFAULT;
}

Contributors
Person Tokens Prop Commits CommitProp
Linus Torvalds (pre-git) 99 46.26% 4 36.36%
Andrew Morton 64 29.91% 2 18.18%
David Howells 30 14.02% 1 9.09%
Miklos Szeredi 10 4.67% 1 9.09%
Al Viro 9 4.21% 1 9.09%
Linus Torvalds 2 0.93% 2 18.18%
Total 214 100.00% 11 100.00%


SYSCALL_DEFINE3(old_readdir, unsigned int, fd,
		struct old_linux_dirent __user *, dirent, unsigned int, count)
{
	int error;
	struct fd f = fdget_pos(fd);
	struct readdir_callback buf = {
		.ctx.actor = fillonedir,
		.dirent = dirent
	};

	if (!f.file)
		return -EBADF;

	error = iterate_dir(f.file, &buf.ctx);
	if (buf.result)
		error = buf.result;

	fdput_pos(f);
	return error;
}

#endif /* __ARCH_WANT_OLD_READDIR */

/*
 * New, all-improved, singing, dancing, iBCS2-compliant getdents()
 * interface. 
 */

struct linux_dirent {
	
unsigned long	d_ino;
	
unsigned long	d_off;
	
unsigned short	d_reclen;
	
char		d_name[1];
};


struct getdents_callback {
	
struct dir_context ctx;
	
struct linux_dirent __user * current_dir;
	
struct linux_dirent __user * previous;
	
int count;
	
int error;
};



static int filldir(struct dir_context *ctx, const char *name, int namlen,
		   loff_t offset, u64 ino, unsigned int d_type)
{
	struct linux_dirent __user * dirent;
	struct getdents_callback *buf =
		container_of(ctx, struct getdents_callback, ctx);
	unsigned long d_ino;
	int reclen = ALIGN(offsetof(struct linux_dirent, d_name) + namlen + 2,
		sizeof(long));

	buf->error = -EINVAL;	/* only used if we fail.. */
	if (reclen > buf->count)
		return -EINVAL;
	d_ino = ino;
	if (sizeof(d_ino) < sizeof(ino) && d_ino != ino) {
		buf->error = -EOVERFLOW;
		return -EOVERFLOW;
	}
	dirent = buf->previous;
	if (dirent) {
		if (signal_pending(current))
			return -EINTR;
		if (__put_user(offset, &dirent->d_off))
			goto efault;
	}
	dirent = buf->current_dir;
	if (__put_user(d_ino, &dirent->d_ino))
		goto efault;
	if (__put_user(reclen, &dirent->d_reclen))
		goto efault;
	if (copy_to_user(dirent->d_name, name, namlen))
		goto efault;
	if (__put_user(0, dirent->d_name + namlen))
		goto efault;
	if (__put_user(d_type, (char __user *) dirent + reclen - 1))
		goto efault;
	buf->previous = dirent;
	dirent = (void __user *)dirent + reclen;
	buf->current_dir = dirent;
	buf->count -= reclen;
	return 0;
efault:
	buf->error = -EFAULT;
	return -EFAULT;
}

Contributors
Person Tokens Prop Commits CommitProp
Linus Torvalds (pre-git) 147 48.68% 7 31.82%
Andrew Morton 55 18.21% 3 13.64%
David Howells 30 9.93% 1 4.55%
Linus Torvalds 28 9.27% 5 22.73%
Theodore Y. Ts'o 11 3.64% 1 4.55%
Miklos Szeredi 10 3.31% 1 4.55%
Al Viro 10 3.31% 2 9.09%
Milind Arun Choudhary 6 1.99% 1 4.55%
Kevin Winchester 5 1.66% 1 4.55%
Total 302 100.00% 22 100.00%


SYSCALL_DEFINE3(getdents, unsigned int, fd,
		struct linux_dirent __user *, dirent, unsigned int, count)
{
	struct fd f;
	struct linux_dirent __user * lastdirent;
	struct getdents_callback buf = {
		.ctx.actor = filldir,
		.count = count,
		.current_dir = dirent
	};
	int error;

	if (!access_ok(VERIFY_WRITE, dirent, count))
		return -EFAULT;

	f = fdget_pos(fd);
	if (!f.file)
		return -EBADF;

	error = iterate_dir(f.file, &buf.ctx);
	if (error >= 0)
		error = buf.error;
	lastdirent = buf.previous;
	if (lastdirent) {
		if (put_user(buf.ctx.pos, &lastdirent->d_off))
			error = -EFAULT;
		else
			error = count - buf.count;
	}
	fdput_pos(f);
	return error;
}


struct getdents_callback64 {
	
struct dir_context ctx;
	
struct linux_dirent64 __user * current_dir;
	
struct linux_dirent64 __user * previous;
	
int count;
	
int error;
};



static int filldir64(struct dir_context *ctx, const char *name, int namlen,
		     loff_t offset, u64 ino, unsigned int d_type)
{
	struct linux_dirent64 __user *dirent;
	struct getdents_callback64 *buf =
		container_of(ctx, struct getdents_callback64, ctx);
	int reclen = ALIGN(offsetof(struct linux_dirent64, d_name) + namlen + 1,
		sizeof(u64));

	buf->error = -EINVAL;	/* only used if we fail.. */
	if (reclen > buf->count)
		return -EINVAL;
	dirent = buf->previous;
	if (dirent) {
		if (signal_pending(current))
			return -EINTR;
		if (__put_user(offset, &dirent->d_off))
			goto efault;
	}
	dirent = buf->current_dir;
	if (__put_user(ino, &dirent->d_ino))
		goto efault;
	if (__put_user(0, &dirent->d_off))
		goto efault;
	if (__put_user(reclen, &dirent->d_reclen))
		goto efault;
	if (__put_user(d_type, &dirent->d_type))
		goto efault;
	if (copy_to_user(dirent->d_name, name, namlen))
		goto efault;
	if (__put_user(0, dirent->d_name + namlen))
		goto efault;
	buf->previous = dirent;
	dirent = (void __user *)dirent + reclen;
	buf->current_dir = dirent;
	buf->count -= reclen;
	return 0;
efault:
	buf->error = -EFAULT;
	return -EFAULT;
}

Contributors
Person Tokens Prop Commits CommitProp
Linus Torvalds (pre-git) 142 51.82% 1 7.14%
Andrew Morton 93 33.94% 3 21.43%
Theodore Y. Ts'o 11 4.01% 1 7.14%
Miklos Szeredi 10 3.65% 1 7.14%
Milind Arun Choudhary 6 2.19% 1 7.14%
Linus Torvalds 6 2.19% 5 35.71%
Kevin Winchester 5 1.82% 1 7.14%
David Howells 1 0.36% 1 7.14%
Total 274 100.00% 14 100.00%


SYSCALL_DEFINE3(getdents64, unsigned int, fd,
		struct linux_dirent64 __user *, dirent, unsigned int, count)
{
	struct fd f;
	struct linux_dirent64 __user * lastdirent;
	struct getdents_callback64 buf = {
		.ctx.actor = filldir64,
		.count = count,
		.current_dir = dirent
	};
	int error;

	if (!access_ok(VERIFY_WRITE, dirent, count))
		return -EFAULT;

	f = fdget_pos(fd);
	if (!f.file)
		return -EBADF;

	error = iterate_dir(f.file, &buf.ctx);
	if (error >= 0)
		error = buf.error;
	lastdirent = buf.previous;
	if (lastdirent) {
		typeof(lastdirent->d_off) d_off = buf.ctx.pos;
		if (__put_user(d_off, &lastdirent->d_off))
			error = -EFAULT;
		else
			error = count - buf.count;
	}
	fdput_pos(f);
	return error;
}

#ifdef CONFIG_COMPAT

struct compat_old_linux_dirent {
	
compat_ulong_t	d_ino;
	
compat_ulong_t	d_offset;
	
unsigned short	d_namlen;
	
char		d_name[1];
};


struct compat_readdir_callback {
	
struct dir_context ctx;
	
struct compat_old_linux_dirent __user *dirent;
	
int result;
};



static int compat_fillonedir(struct dir_context *ctx, const char *name,
			     int namlen, loff_t offset, u64 ino,
			     unsigned int d_type)
{
	struct compat_readdir_callback *buf =
		container_of(ctx, struct compat_readdir_callback, ctx);
	struct compat_old_linux_dirent __user *dirent;
	compat_ulong_t d_ino;

	if (buf->result)
		return -EINVAL;
	d_ino = ino;
	if (sizeof(d_ino) < sizeof(ino) && d_ino != ino) {
		buf->result = -EOVERFLOW;
		return -EOVERFLOW;
	}
	buf->result++;
	dirent = buf->dirent;
	if (!access_ok(VERIFY_WRITE, dirent,
			(unsigned long)(dirent->d_name + namlen + 1) -
				(unsigned long)dirent))
		goto efault;
	if (	__put_user(d_ino, &dirent->d_ino) ||
		__put_user(offset, &dirent->d_offset) ||
		__put_user(namlen, &dirent->d_namlen) ||
		__copy_to_user(dirent->d_name, name, namlen) ||
		__put_user(0, dirent->d_name + namlen))
		goto efault;
	return 0;
efault:
	buf->result = -EFAULT;
	return -EFAULT;
}

Contributors
Person Tokens Prop Commits CommitProp
Al Viro 213 100.00% 1 100.00%
Total 213 100.00% 1 100.00%


COMPAT_SYSCALL_DEFINE3(old_readdir, unsigned int, fd,
		struct compat_old_linux_dirent __user *, dirent, unsigned int, count)
{
	int error;
	struct fd f = fdget_pos(fd);
	struct compat_readdir_callback buf = {
		.ctx.actor = compat_fillonedir,
		.dirent = dirent
	};

	if (!f.file)
		return -EBADF;

	error = iterate_dir(f.file, &buf.ctx);
	if (buf.result)
		error = buf.result;

	fdput_pos(f);
	return error;
}


struct compat_linux_dirent {
	
compat_ulong_t	d_ino;
	
compat_ulong_t	d_off;
	
unsigned short	d_reclen;
	
char		d_name[1];
};


struct compat_getdents_callback {
	
struct dir_context ctx;
	
struct compat_linux_dirent __user *current_dir;
	
struct compat_linux_dirent __user *previous;
	
int count;
	
int error;
};



static int compat_filldir(struct dir_context *ctx, const char *name, int namlen,
		loff_t offset, u64 ino, unsigned int d_type)
{
	struct compat_linux_dirent __user * dirent;
	struct compat_getdents_callback *buf =
		container_of(ctx, struct compat_getdents_callback, ctx);
	compat_ulong_t d_ino;
	int reclen = ALIGN(offsetof(struct compat_linux_dirent, d_name) +
		namlen + 2, sizeof(compat_long_t));

	buf->error = -EINVAL;	/* only used if we fail.. */
	if (reclen > buf->count)
		return -EINVAL;
	d_ino = ino;
	if (sizeof(d_ino) < sizeof(ino) && d_ino != ino) {
		buf->error = -EOVERFLOW;
		return -EOVERFLOW;
	}
	dirent = buf->previous;
	if (dirent) {
		if (signal_pending(current))
			return -EINTR;
		if (__put_user(offset, &dirent->d_off))
			goto efault;
	}
	dirent = buf->current_dir;
	if (__put_user(d_ino, &dirent->d_ino))
		goto efault;
	if (__put_user(reclen, &dirent->d_reclen))
		goto efault;
	if (copy_to_user(dirent->d_name, name, namlen))
		goto efault;
	if (__put_user(0, dirent->d_name + namlen))
		goto efault;
	if (__put_user(d_type, (char  __user *) dirent + reclen - 1))
		goto efault;
	buf->previous = dirent;
	dirent = (void __user *)dirent + reclen;
	buf->current_dir = dirent;
	buf->count -= reclen;
	return 0;
efault:
	buf->error = -EFAULT;
	return -EFAULT;
}

Contributors
Person Tokens Prop Commits CommitProp
Al Viro 301 100.00% 1 100.00%
Total 301 100.00% 1 100.00%


COMPAT_SYSCALL_DEFINE3(getdents, unsigned int, fd,
		struct compat_linux_dirent __user *, dirent, unsigned int, count)
{
	struct fd f;
	struct compat_linux_dirent __user * lastdirent;
	struct compat_getdents_callback buf = {
		.ctx.actor = compat_filldir,
		.current_dir = dirent,
		.count = count
	};
	int error;

	if (!access_ok(VERIFY_WRITE, dirent, count))
		return -EFAULT;

	f = fdget_pos(fd);
	if (!f.file)
		return -EBADF;

	error = iterate_dir(f.file, &buf.ctx);
	if (error >= 0)
		error = buf.error;
	lastdirent = buf.previous;
	if (lastdirent) {
		if (put_user(buf.ctx.pos, &lastdirent->d_off))
			error = -EFAULT;
		else
			error = count - buf.count;
	}
	fdput_pos(f);
	return error;
}
#endif
Overall Contributors
Person Tokens Prop Commits CommitProp
Al Viro 1147 46.59% 15 23.44%
Linus Torvalds (pre-git) 765 31.07% 16 25.00%
Andrew Morton 251 10.19% 8 12.50%
Linus Torvalds 62 2.52% 7 10.94%
David Howells 61 2.48% 1 1.56%
Heiko Carstens 48 1.95% 2 3.12%
Miklos Szeredi 30 1.22% 1 1.56%
Theodore Y. Ts'o 22 0.89% 1 1.56%
Milind Arun Choudhary 15 0.61% 1 1.56%
Kevin Winchester 13 0.53% 1 1.56%
Stephen D. Smalley 11 0.45% 1 1.56%
Heinrich Schuchardt 8 0.32% 1 1.56%
Greg Kroah-Hartman 8 0.32% 3 4.69%
Arnaldo Carvalho de Melo 6 0.24% 1 1.56%
Adam Kropelin 4 0.16% 1 1.56%
Dave Jones 4 0.16% 1 1.56%
Prasanna Meda 3 0.12% 1 1.56%
Arnd Bergmann 3 0.12% 1 1.56%
Paul Gortmaker 1 0.04% 1 1.56%
Total 2462 100.00% 64 100.00%
Directory: fs

Information contained on this website is for historical information purposes only and does not indicate or represent copyright ownership.
Created with cregit.
Person	Tokens	Prop	Commits	CommitProp
Al Viro	114	57.00%	7	46.67%
Linus Torvalds (pre-git)	62	31.00%	3	20.00%
Stephen D. Smalley	11	5.50%	1	6.67%
Heinrich Schuchardt	5	2.50%	1	6.67%
Greg Kroah-Hartman	5	2.50%	2	13.33%
Andrew Morton	3	1.50%	1	6.67%
Total	200	100.00%	15	100.00%
cregit-Linux how code gets into the kernel

Release 4.12 fs/readdir.c

Contributors

Contributors

Contributors

Contributors

Contributors

Contributors

Overall Contributors
