[linux.git] / fs / readdir.c

// SPDX-License-Identifier: GPL-2.0
/*
 *  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)
		res = down_read_killable(&inode->i_rwsem);
	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;
}
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(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;
}

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;
}

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(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;
}

int ksys_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(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;
}


SYSCALL_DEFINE3(getdents64, unsigned int, fd,
		struct linux_dirent64 __user *, dirent, unsigned int, count)
{
	return ksys_getdents64(fd, dirent, count);
}

#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(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;
}

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;
}

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(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
Commit	Line	Data
b2441318	1	// SPDX-License-Identifier: GPL-2.0
1da177e4 LT	2	/*
	3	* linux/fs/readdir.c
	4	*
	5	* Copyright (C) 1995 Linus Torvalds
	6	*/
	7
85c9fe8f	8	#include <linux/stddef.h>
022a1692	9	#include <linux/kernel.h>
630d9c47	10	#include <linux/export.h>
1da177e4 LT	11	#include <linux/time.h>
	12	#include <linux/mm.h>
	13	#include <linux/errno.h>
	14	#include <linux/stat.h>
	15	#include <linux/file.h>
1da177e4	16	#include <linux/fs.h>
d4c7cf6c	17	#include <linux/fsnotify.h>
1da177e4 LT	18	#include <linux/dirent.h>
	19	#include <linux/security.h>
	20	#include <linux/syscalls.h>
	21	#include <linux/unistd.h>
0460b2a2	22	#include <linux/compat.h>
1da177e4	23
7c0f6ba6	24	#include <linux/uaccess.h>
1da177e4	25
5c0ba4e0	26	int iterate_dir(struct file file, struct dir_context ctx)
1da177e4	27	{
496ad9aa	28	struct inode *inode = file_inode(file);
61922694	29	bool shared = false;
1da177e4	30	int res = -ENOTDIR;
61922694 AV	31	if (file->f_op->iterate_shared)
	32	shared = true;
	33	else if (!file->f_op->iterate)
1da177e4 LT	34	goto out;
	35
	36	res = security_file_permission(file, MAY_READ);
	37	if (res)
	38	goto out;
	39
0dc208b5 KT	40	if (shared)
	41	res = down_read_killable(&inode->i_rwsem);
	42	else
00235411	43	res = down_write_killable(&inode->i_rwsem);
0dc208b5 KT	44	if (res)
0dc208b5 KT	45	goto out;
da784511	46
1da177e4 LT	47	res = -ENOENT;
1da177e4 LT	48	if (!IS_DEADDIR(inode)) {
2233f31a	49	ctx->pos = file->f_pos;
61922694 AV	50	if (shared)
	51	res = file->f_op->iterate_shared(file, ctx);
	52	else
	53	res = file->f_op->iterate(file, ctx);
2233f31a	54	file->f_pos = ctx->pos;
d4c7cf6c	55	fsnotify_access(file);
1da177e4 LT	56	file_accessed(file);
1da177e4 LT	57	}
61922694 AV	58	if (shared)
	59	inode_unlock_shared(inode);
	60	else
	61	inode_unlock(inode);
1da177e4 LT	62	out:
	63	return res;
	64	}
5c0ba4e0	65	EXPORT_SYMBOL(iterate_dir);
1da177e4 LT	66
	67	/*
	68	* Traditional linux readdir() handling..
	69	*
	70	* "count=1" is a special case, meaning that the buffer is one
	71	* dirent-structure in size and that the code can't handle more
	72	* anyway. Thus the special "fillonedir()" function for that
	73	* case (the low-level handlers don't need to care about this).
	74	*/
1da177e4 LT	75
	76	#ifdef __ARCH_WANT_OLD_READDIR
	77
	78	struct old_linux_dirent {
	79	unsigned long d_ino;
	80	unsigned long d_offset;
	81	unsigned short d_namlen;
	82	char d_name[1];
	83	};
	84
	85	struct readdir_callback {
5c0ba4e0	86	struct dir_context ctx;
1da177e4 LT	87	struct old_linux_dirent __user * dirent;
	88	int result;
	89	};
	90
ac7576f4 MS	91	static int fillonedir(struct dir_context ctx, const char name, int namlen,
ac7576f4 MS	92	loff_t offset, u64 ino, unsigned int d_type)
1da177e4	93	{
ac7576f4 MS	94	struct readdir_callback *buf =
ac7576f4 MS	95	container_of(ctx, struct readdir_callback, ctx);
1da177e4	96	struct old_linux_dirent __user * dirent;
afefdbb2	97	unsigned long d_ino;
1da177e4 LT	98
	99	if (buf->result)
	100	return -EINVAL;
afefdbb2	101	d_ino = ino;
8f3f655d AV	102	if (sizeof(d_ino) < sizeof(ino) && d_ino != ino) {
8f3f655d AV	103	buf->result = -EOVERFLOW;
afefdbb2	104	return -EOVERFLOW;
8f3f655d	105	}
1da177e4 LT	106	buf->result++;
1da177e4 LT	107	dirent = buf->dirent;
96d4f267	108	if (!access_ok(dirent,
1da177e4 LT	109	(unsigned long)(dirent->d_name + namlen + 1) -
	110	(unsigned long)dirent))
	111	goto efault;
afefdbb2	112	if ( __put_user(d_ino, &dirent->d_ino) \|\|
1da177e4 LT	113	__put_user(offset, &dirent->d_offset) \|\|
	114	__put_user(namlen, &dirent->d_namlen) \|\|
	115	__copy_to_user(dirent->d_name, name, namlen) \|\|
	116	__put_user(0, dirent->d_name + namlen))
	117	goto efault;
	118	return 0;
	119	efault:
	120	buf->result = -EFAULT;
	121	return -EFAULT;
	122	}
	123
d4e82042 HC	124	SYSCALL_DEFINE3(old_readdir, unsigned int, fd,
d4e82042 HC	125	struct old_linux_dirent __user *, dirent, unsigned int, count)
1da177e4 LT	126	{
1da177e4 LT	127	int error;
63b6df14	128	struct fd f = fdget_pos(fd);
ac6614b7 AV	129	struct readdir_callback buf = {
	130	.ctx.actor = fillonedir,
	131	.dirent = dirent
	132	};
1da177e4	133
2903ff01	134	if (!f.file)
863ced7f	135	return -EBADF;
1da177e4	136
5c0ba4e0	137	error = iterate_dir(f.file, &buf.ctx);
53c9c5c0	138	if (buf.result)
1da177e4 LT	139	error = buf.result;
1da177e4 LT	140
63b6df14	141	fdput_pos(f);
1da177e4 LT	142	return error;
	143	}
	144
	145	#endif /* __ARCH_WANT_OLD_READDIR */
	146
	147	/*
	148	* New, all-improved, singing, dancing, iBCS2-compliant getdents()
	149	* interface.
	150	*/
	151	struct linux_dirent {
	152	unsigned long d_ino;
	153	unsigned long d_off;
	154	unsigned short d_reclen;
	155	char d_name[1];
	156	};
	157
	158	struct getdents_callback {
5c0ba4e0	159	struct dir_context ctx;
1da177e4 LT	160	struct linux_dirent __user * current_dir;
	161	struct linux_dirent __user * previous;
	162	int count;
	163	int error;
	164	};
	165
ac7576f4 MS	166	static int filldir(struct dir_context ctx, const char name, int namlen,
ac7576f4 MS	167	loff_t offset, u64 ino, unsigned int d_type)
1da177e4 LT	168	{
1da177e4 LT	169	struct linux_dirent __user * dirent;
ac7576f4 MS	170	struct getdents_callback *buf =
ac7576f4 MS	171	container_of(ctx, struct getdents_callback, ctx);
afefdbb2	172	unsigned long d_ino;
85c9fe8f KW	173	int reclen = ALIGN(offsetof(struct linux_dirent, d_name) + namlen + 2,
85c9fe8f KW	174	sizeof(long));
1da177e4 LT	175
	176	buf->error = -EINVAL; /* only used if we fail.. */
	177	if (reclen > buf->count)
	178	return -EINVAL;
afefdbb2	179	d_ino = ino;
8f3f655d AV	180	if (sizeof(d_ino) < sizeof(ino) && d_ino != ino) {
8f3f655d AV	181	buf->error = -EOVERFLOW;
afefdbb2	182	return -EOVERFLOW;
8f3f655d	183	}
1da177e4 LT	184	dirent = buf->previous;
1da177e4 LT	185	if (dirent) {
1f60fbe7 TT	186	if (signal_pending(current))
1f60fbe7 TT	187	return -EINTR;
1da177e4 LT	188	if (__put_user(offset, &dirent->d_off))
	189	goto efault;
	190	}
	191	dirent = buf->current_dir;
afefdbb2	192	if (__put_user(d_ino, &dirent->d_ino))
1da177e4 LT	193	goto efault;
	194	if (__put_user(reclen, &dirent->d_reclen))
	195	goto efault;
	196	if (copy_to_user(dirent->d_name, name, namlen))
	197	goto efault;
	198	if (__put_user(0, dirent->d_name + namlen))
	199	goto efault;
	200	if (__put_user(d_type, (char __user *) dirent + reclen - 1))
	201	goto efault;
	202	buf->previous = dirent;
	203	dirent = (void __user *)dirent + reclen;
	204	buf->current_dir = dirent;
	205	buf->count -= reclen;
	206	return 0;
	207	efault:
	208	buf->error = -EFAULT;
	209	return -EFAULT;
	210	}
	211
20f37034 HC	212	SYSCALL_DEFINE3(getdents, unsigned int, fd,
20f37034 HC	213	struct linux_dirent __user *, dirent, unsigned int, count)
1da177e4	214	{
2903ff01	215	struct fd f;
1da177e4	216	struct linux_dirent __user * lastdirent;
ac6614b7 AV	217	struct getdents_callback buf = {
	218	.ctx.actor = filldir,
	219	.count = count,
	220	.current_dir = dirent
	221	};
1da177e4 LT	222	int error;
1da177e4 LT	223
96d4f267	224	if (!access_ok(dirent, count))
863ced7f	225	return -EFAULT;
1da177e4	226
63b6df14	227	f = fdget_pos(fd);
2903ff01	228	if (!f.file)
863ced7f	229	return -EBADF;
1da177e4	230
5c0ba4e0	231	error = iterate_dir(f.file, &buf.ctx);
53c9c5c0 AV	232	if (error >= 0)
53c9c5c0 AV	233	error = buf.error;
1da177e4 LT	234	lastdirent = buf.previous;
1da177e4 LT	235	if (lastdirent) {
bb6f619b	236	if (put_user(buf.ctx.pos, &lastdirent->d_off))
1da177e4 LT	237	error = -EFAULT;
	238	else
	239	error = count - buf.count;
	240	}
63b6df14	241	fdput_pos(f);
1da177e4 LT	242	return error;
	243	}
	244
1da177e4	245	struct getdents_callback64 {
5c0ba4e0	246	struct dir_context ctx;
1da177e4 LT	247	struct linux_dirent64 __user * current_dir;
	248	struct linux_dirent64 __user * previous;
	249	int count;
	250	int error;
	251	};
	252
ac7576f4 MS	253	static int filldir64(struct dir_context ctx, const char name, int namlen,
ac7576f4 MS	254	loff_t offset, u64 ino, unsigned int d_type)
1da177e4 LT	255	{
1da177e4 LT	256	struct linux_dirent64 __user *dirent;
ac7576f4 MS	257	struct getdents_callback64 *buf =
ac7576f4 MS	258	container_of(ctx, struct getdents_callback64, ctx);
85c9fe8f KW	259	int reclen = ALIGN(offsetof(struct linux_dirent64, d_name) + namlen + 1,
85c9fe8f KW	260	sizeof(u64));
1da177e4 LT	261
	262	buf->error = -EINVAL; /* only used if we fail.. */
	263	if (reclen > buf->count)
	264	return -EINVAL;
	265	dirent = buf->previous;
	266	if (dirent) {
1f60fbe7 TT	267	if (signal_pending(current))
1f60fbe7 TT	268	return -EINTR;
1da177e4 LT	269	if (__put_user(offset, &dirent->d_off))
	270	goto efault;
	271	}
	272	dirent = buf->current_dir;
	273	if (__put_user(ino, &dirent->d_ino))
	274	goto efault;
	275	if (__put_user(0, &dirent->d_off))
	276	goto efault;
	277	if (__put_user(reclen, &dirent->d_reclen))
	278	goto efault;
	279	if (__put_user(d_type, &dirent->d_type))
	280	goto efault;
	281	if (copy_to_user(dirent->d_name, name, namlen))
	282	goto efault;
	283	if (__put_user(0, dirent->d_name + namlen))
	284	goto efault;
	285	buf->previous = dirent;
	286	dirent = (void __user *)dirent + reclen;
	287	buf->current_dir = dirent;
	288	buf->count -= reclen;
	289	return 0;
	290	efault:
	291	buf->error = -EFAULT;
	292	return -EFAULT;
	293	}
	294
454dab3f DB	295	int ksys_getdents64(unsigned int fd, struct linux_dirent64 __user *dirent,
454dab3f DB	296	unsigned int count)
1da177e4	297	{
2903ff01	298	struct fd f;
1da177e4	299	struct linux_dirent64 __user * lastdirent;
ac6614b7 AV	300	struct getdents_callback64 buf = {
	301	.ctx.actor = filldir64,
	302	.count = count,
	303	.current_dir = dirent
	304	};
1da177e4 LT	305	int error;
1da177e4 LT	306
96d4f267	307	if (!access_ok(dirent, count))
863ced7f	308	return -EFAULT;
1da177e4	309
63b6df14	310	f = fdget_pos(fd);
2903ff01	311	if (!f.file)
863ced7f	312	return -EBADF;
1da177e4	313
5c0ba4e0	314	error = iterate_dir(f.file, &buf.ctx);
53c9c5c0 AV	315	if (error >= 0)
53c9c5c0 AV	316	error = buf.error;
1da177e4 LT	317	lastdirent = buf.previous;
1da177e4 LT	318	if (lastdirent) {
bb6f619b	319	typeof(lastdirent->d_off) d_off = buf.ctx.pos;
1da177e4	320	if (__put_user(d_off, &lastdirent->d_off))
53c9c5c0 AV	321	error = -EFAULT;
	322	else
	323	error = count - buf.count;
1da177e4	324	}
63b6df14	325	fdput_pos(f);
1da177e4 LT	326	return error;
1da177e4 LT	327	}
0460b2a2	328
454dab3f DB	329
	330	SYSCALL_DEFINE3(getdents64, unsigned int, fd,
	331	struct linux_dirent64 __user *, dirent, unsigned int, count)
	332	{
	333	return ksys_getdents64(fd, dirent, count);
	334	}
	335
0460b2a2 AV	336	#ifdef CONFIG_COMPAT
	337	struct compat_old_linux_dirent {
	338	compat_ulong_t d_ino;
	339	compat_ulong_t d_offset;
	340	unsigned short d_namlen;
	341	char d_name[1];
	342	};
	343
	344	struct compat_readdir_callback {
	345	struct dir_context ctx;
	346	struct compat_old_linux_dirent __user *dirent;
	347	int result;
	348	};
	349
	350	static int compat_fillonedir(struct dir_context ctx, const char name,
	351	int namlen, loff_t offset, u64 ino,
	352	unsigned int d_type)
	353	{
	354	struct compat_readdir_callback *buf =
	355	container_of(ctx, struct compat_readdir_callback, ctx);
	356	struct compat_old_linux_dirent __user *dirent;
	357	compat_ulong_t d_ino;
	358
	359	if (buf->result)
	360	return -EINVAL;
	361	d_ino = ino;
	362	if (sizeof(d_ino) < sizeof(ino) && d_ino != ino) {
	363	buf->result = -EOVERFLOW;
	364	return -EOVERFLOW;
	365	}
	366	buf->result++;
	367	dirent = buf->dirent;
96d4f267	368	if (!access_ok(dirent,
0460b2a2 AV	369	(unsigned long)(dirent->d_name + namlen + 1) -
	370	(unsigned long)dirent))
	371	goto efault;
	372	if ( __put_user(d_ino, &dirent->d_ino) \|\|
	373	__put_user(offset, &dirent->d_offset) \|\|
	374	__put_user(namlen, &dirent->d_namlen) \|\|
	375	__copy_to_user(dirent->d_name, name, namlen) \|\|
	376	__put_user(0, dirent->d_name + namlen))
	377	goto efault;
	378	return 0;
	379	efault:
	380	buf->result = -EFAULT;
	381	return -EFAULT;
	382	}
	383
	384	COMPAT_SYSCALL_DEFINE3(old_readdir, unsigned int, fd,
	385	struct compat_old_linux_dirent __user *, dirent, unsigned int, count)
	386	{
	387	int error;
	388	struct fd f = fdget_pos(fd);
	389	struct compat_readdir_callback buf = {
	390	.ctx.actor = compat_fillonedir,
	391	.dirent = dirent
	392	};
	393
	394	if (!f.file)
	395	return -EBADF;
	396
	397	error = iterate_dir(f.file, &buf.ctx);
	398	if (buf.result)
	399	error = buf.result;
	400
	401	fdput_pos(f);
	402	return error;
	403	}
	404
	405	struct compat_linux_dirent {
	406	compat_ulong_t d_ino;
	407	compat_ulong_t d_off;
	408	unsigned short d_reclen;
	409	char d_name[1];
	410	};
	411
	412	struct compat_getdents_callback {
	413	struct dir_context ctx;
	414	struct compat_linux_dirent __user *current_dir;
	415	struct compat_linux_dirent __user *previous;
	416	int count;
	417	int error;
	418	};
	419
	420	static int compat_filldir(struct dir_context ctx, const char name, int namlen,
	421	loff_t offset, u64 ino, unsigned int d_type)
	422	{
	423	struct compat_linux_dirent __user * dirent;
	424	struct compat_getdents_callback *buf =
	425	container_of(ctx, struct compat_getdents_callback, ctx);
	426	compat_ulong_t d_ino;
	427	int reclen = ALIGN(offsetof(struct compat_linux_dirent, d_name) +
	428	namlen + 2, sizeof(compat_long_t));
	429
	430	buf->error = -EINVAL; /* only used if we fail.. */
	431	if (reclen > buf->count)
	432	return -EINVAL;
433	d_ino = ino;
434	if (sizeof(d_ino) < sizeof(ino) && d_ino != ino) {
435	buf->error = -EOVERFLOW;
436	return -EOVERFLOW;
437	}
438	dirent = buf->previous;
439	if (dirent) {
440	if (signal_pending(current))
441	return -EINTR;
442	if (__put_user(offset, &dirent->d_off))
443	goto efault;
444	}
445	dirent = buf->current_dir;
446	if (__put_user(d_ino, &dirent->d_ino))
447	goto efault;
448	if (__put_user(reclen, &dirent->d_reclen))
449	goto efault;
450	if (copy_to_user(dirent->d_name, name, namlen))
451	goto efault;
452	if (__put_user(0, dirent->d_name + namlen))
453	goto efault;
454	if (__put_user(d_type, (char __user *) dirent + reclen - 1))
455	goto efault;
456	buf->previous = dirent;
457	dirent = (void __user *)dirent + reclen;
458	buf->current_dir = dirent;
459	buf->count -= reclen;
460	return 0;
461	efault:
462	buf->error = -EFAULT;
463	return -EFAULT;
464	}
465
466	COMPAT_SYSCALL_DEFINE3(getdents, unsigned int, fd,
467	struct compat_linux_dirent __user *, dirent, unsigned int, count)
468	{
469	struct fd f;
470	struct compat_linux_dirent __user * lastdirent;
471	struct compat_getdents_callback buf = {
472	.ctx.actor = compat_filldir,
473	.current_dir = dirent,
474	.count = count
475	};
476	int error;
477
96d4f267	478	if (!access_ok(dirent, count))
0460b2a2 AV	479	return -EFAULT;
	480
	481	f = fdget_pos(fd);
	482	if (!f.file)
	483	return -EBADF;
	484
	485	error = iterate_dir(f.file, &buf.ctx);
	486	if (error >= 0)
	487	error = buf.error;
	488	lastdirent = buf.previous;
	489	if (lastdirent) {
	490	if (put_user(buf.ctx.pos, &lastdirent->d_off))
	491	error = -EFAULT;
	492	else
	493	error = count - buf.count;
	494	}
	495	fdput_pos(f);
	496	return error;
	497	}
	498	#endif