Commit 2611dc19 authored by Al Viro's avatar Al Viro
Browse files

Remove compat_sys_getdents64() 



Unlike normal compat syscall variants, it is needed only for
biarch architectures that have different alignement requirements for
u64 in 32bit and 64bit ABI *and* have __put_user() that won't handle
a store of 64bit value at 32bit-aligned address.  We used to have one
such (ia64), but its biarch support has been gone since 2010 (after
being broken in 2008, which went unnoticed since nobody had been using
it).

It had escaped removal at the same time only because back in 2004
a patch that switched several syscalls on amd64 from private wrappers to
generic compat ones had switched to use of compat_sys_getdents64(), which
hadn't needed (or used) a compat wrapper on amd64.

Let's bury it - it's at least 7 years overdue.

Signed-off-by: default avatarAl Viro <viro@zeniv.linux.org.uk>
parent a71c9a1c

arch/arm64/include/asm/unistd.h

+0 −1
Original line number Diff line number Diff line
@@ -14,7 +14,6 @@ 
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.

 */

#ifdef CONFIG_COMPAT

#define __ARCH_WANT_COMPAT_SYS_GETDENTS64

#define __ARCH_WANT_COMPAT_STAT64

#define __ARCH_WANT_SYS_GETHOSTNAME

#define __ARCH_WANT_SYS_PAUSE

arch/arm64/include/asm/unistd32.h

+1 −1
Original line number Diff line number Diff line
@@ -456,7 +456,7 @@ __SYSCALL(__NR_setfsuid32, sys_setfsuid) 
#define __NR_setfsgid32 216

__SYSCALL(__NR_setfsgid32, sys_setfsgid)

#define __NR_getdents64 217

__SYSCALL(__NR_getdents64, compat_sys_getdents64)

__SYSCALL(__NR_getdents64, sys_getdents64)

#define __NR_pivot_root 218

__SYSCALL(__NR_pivot_root, sys_pivot_root)

#define __NR_mincore 219

arch/x86/entry/syscalls/syscall_32.tbl

+1 −1
Original line number Diff line number Diff line
@@ -226,7 +226,7 @@ 
217	i386	pivot_root		sys_pivot_root

218	i386	mincore			sys_mincore

219	i386	madvise			sys_madvise

220	i386	getdents64		sys_getdents64			compat_sys_getdents64

220	i386	getdents64		sys_getdents64

221	i386	fcntl64			sys_fcntl64			compat_sys_fcntl64

# 222 is unused

# 223 is unused

arch/x86/include/asm/unistd.h

+0 −1
Original line number Diff line number Diff line
@@ -23,7 +23,6 @@ 
#  include <asm/unistd_64.h>

#  include <asm/unistd_64_x32.h>

#  define __ARCH_WANT_COMPAT_SYS_TIME

#  define __ARCH_WANT_COMPAT_SYS_GETDENTS64

#  define __ARCH_WANT_COMPAT_SYS_PREADV64

#  define __ARCH_WANT_COMPAT_SYS_PWRITEV64

#  define __ARCH_WANT_COMPAT_SYS_PREADV64V2

fs/compat.c

+0 −91
Original line number Diff line number Diff line
@@ -907,97 +907,6 @@ COMPAT_SYSCALL_DEFINE3(getdents, unsigned int, fd, 
	return error;

}



#ifdef __ARCH_WANT_COMPAT_SYS_GETDENTS64



struct compat_getdents_callback64 {

	struct dir_context ctx;

	struct linux_dirent64 __user *current_dir;

	struct linux_dirent64 __user *previous;

	int count;

	int error;

};



static int compat_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 compat_getdents_callback64 *buf =

		container_of(ctx, struct compat_getdents_callback64, ctx);

	int reclen = ALIGN(offsetof(struct linux_dirent64, d_name) + namlen + 1,

		sizeof(u64));

	u64 off;



	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_unaligned(offset, &dirent->d_off))

			goto efault;

	}

	dirent = buf->current_dir;

	if (__put_user_unaligned(ino, &dirent->d_ino))

		goto efault;

	off = 0;

	if (__put_user_unaligned(off, &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;

}



COMPAT_SYSCALL_DEFINE3(getdents64, unsigned int, fd,

		struct linux_dirent64 __user *, dirent, unsigned int, count)

{

	struct fd f;

	struct linux_dirent64 __user * lastdirent;

	struct compat_getdents_callback64 buf = {

		.ctx.actor = compat_filldir64,

		.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) {

		typeof(lastdirent->d_off) d_off = buf.ctx.pos;

		if (__put_user_unaligned(d_off, &lastdirent->d_off))

			error = -EFAULT;

		else

			error = count - buf.count;

	}

	fdput_pos(f);

	return error;

}

#endif /* __ARCH_WANT_COMPAT_SYS_GETDENTS64 */



/*

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

 * O_LARGEFILE flag.

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