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Commit 0460b2a2 authored by Al Viro's avatar Al Viro
Browse files

readdir: move compat syscalls from compat.c 



Signed-off-by: default avatarAl Viro <viro@zeniv.linux.org.uk>
parent 4ada54ee

fs/compat.c

+0 −162
Original line number Diff line number Diff line
@@ -548,168 +548,6 @@ COMPAT_SYSCALL_DEFINE5(mount, const char __user *, dev_name, 
	return retval;

}



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;

}



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(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;

}



/*

 * Exactly like fs/open.c:sys_open(), except that it doesn't set the

 * O_LARGEFILE flag.

fs/readdir.c

+165 −0
Original line number Diff line number Diff line
@@ -18,6 +18,7 @@ 
#include <linux/security.h>

#include <linux/syscalls.h>

#include <linux/unistd.h>

#include <linux/compat.h>



#include <linux/uaccess.h>
@@ -324,3 +325,167 @@ SYSCALL_DEFINE3(getdents64, unsigned int, fd, 
	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;

}



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(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