compat: move cp_compat_stat to common code

struct stat / compat_stat is the same on all architectures, so
cp_compat_stat should be, too.

Turns out it is, except that various architectures have slightly and some
high2lowuid/high2lowgid or the direct assignment instead of the
SET_UID/SET_GID that expands to the correct one anyway.

This patch replaces the arch-specific cp_compat_stat implementations with
a common one based on the x86-64 one.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Acked-by: David S. Miller <davem@davemloft.net> [ sparc bits ]
Acked-by: Kyle McMartin <kyle@mcmartin.ca> [ parisc bits ]
Cc: <linux-arch@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

1 files changed, 39 insertions, 0 deletions

diff --git a/fs/compat.c b/fs/compat.c
index aae13d31612f..5f9ec449c799 100644
--- a/fs/compat.c
+++ b/fs/compat.c
@@ -137,6 +137,45 @@ asmlinkage long compat_sys_utimes(char __user *filename, struct compat_timeval _
         return compat_sys_futimesat(AT_FDCWD, filename, t);
 }
 
+static int cp_compat_stat(struct kstat *stat, struct compat_stat __user *ubuf)
+{
+        compat_ino_t ino = stat->ino;
+        typeof(ubuf->st_uid) uid = 0;
+        typeof(ubuf->st_gid) gid = 0;
+        int err;
+
+        SET_UID(uid, stat->uid);
+        SET_GID(gid, stat->gid);
+
+        if ((u64) stat->size > MAX_NON_LFS ||
+            !old_valid_dev(stat->dev) ||
+            !old_valid_dev(stat->rdev))
+                return -EOVERFLOW;
+        if (sizeof(ino) < sizeof(stat->ino) && ino != stat->ino)
+                return -EOVERFLOW;
+
+        if (clear_user(ubuf, sizeof(*ubuf)))
+                return -EFAULT;
+
+        err  = __put_user(old_encode_dev(stat->dev), &ubuf->st_dev);
+        err |= __put_user(ino, &ubuf->st_ino);
+        err |= __put_user(stat->mode, &ubuf->st_mode);
+        err |= __put_user(stat->nlink, &ubuf->st_nlink);
+        err |= __put_user(uid, &ubuf->st_uid);
+        err |= __put_user(gid, &ubuf->st_gid);
+        err |= __put_user(old_encode_dev(stat->rdev), &ubuf->st_rdev);
+        err |= __put_user(stat->size, &ubuf->st_size);
+        err |= __put_user(stat->atime.tv_sec, &ubuf->st_atime);
+        err |= __put_user(stat->atime.tv_nsec, &ubuf->st_atime_nsec);
+        err |= __put_user(stat->mtime.tv_sec, &ubuf->st_mtime);
+        err |= __put_user(stat->mtime.tv_nsec, &ubuf->st_mtime_nsec);
+        err |= __put_user(stat->ctime.tv_sec, &ubuf->st_ctime);
+        err |= __put_user(stat->ctime.tv_nsec, &ubuf->st_ctime_nsec);
+        err |= __put_user(stat->blksize, &ubuf->st_blksize);
+        err |= __put_user(stat->blocks, &ubuf->st_blocks);
+        return err;
+}
+
 asmlinkage long compat_sys_newstat(char __user * filename,
                 struct compat_stat __user *statbuf)
 {