readdir: move compat syscalls from compat.c
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
diff --git a/fs/readdir.c b/fs/readdir.c
index 0e8a7f3..8965954 100644
--- a/fs/readdir.c
+++ b/fs/readdir.c
@@ -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
