Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/dtor/input

[firefly-linux-kernel-4.4.55.git] / fs / namei.c

diff --git a/fs/namei.c b/fs/namei.c
index 77fd536106cba240ae734083d2ba329027e936ed..78512898d3ba6810b36a9e5128b8a5c84e547a91 100644 (file)
--- a/fs/namei.c
+++ b/fs/namei.c
@@ -3154,7 +3154,8 @@ static int do_tmpfile(int dfd, struct filename *pathname,
        if (error)
                goto out2;
        audit_inode(pathname, nd->path.dentry, 0);
-       error = may_open(&nd->path, op->acc_mode, op->open_flag);
+       /* Don't check for other permissions, the inode was just created */
+       error = may_open(&nd->path, MAY_OPEN, op->open_flag);
        if (error)
                goto out2;
        file->f_path.mnt = nd->path.mnt;
@@ -4209,12 +4210,16 @@ SYSCALL_DEFINE5(renameat2, int, olddfd, const char __user *, oldname,
        bool should_retry = false;
        int error;
 
-       if (flags & ~(RENAME_NOREPLACE | RENAME_EXCHANGE))
+       if (flags & ~(RENAME_NOREPLACE | RENAME_EXCHANGE | RENAME_WHITEOUT))
                return -EINVAL;
 
-       if ((flags & RENAME_NOREPLACE) && (flags & RENAME_EXCHANGE))
+       if ((flags & (RENAME_NOREPLACE | RENAME_WHITEOUT)) &&
+           (flags & RENAME_EXCHANGE))
                return -EINVAL;
 
+       if ((flags & RENAME_WHITEOUT) && !capable(CAP_MKNOD))
+               return -EPERM;
+
 retry:
        from = user_path_parent(olddfd, oldname, &oldnd, lookup_flags);
        if (IS_ERR(from)) {
@@ -4346,6 +4351,20 @@ SYSCALL_DEFINE2(rename, const char __user *, oldname, const char __user *, newna
        return sys_renameat2(AT_FDCWD, oldname, AT_FDCWD, newname, 0);
 }
 
+int vfs_whiteout(struct inode *dir, struct dentry *dentry)
+{
+       int error = may_create(dir, dentry);
+       if (error)
+               return error;
+
+       if (!dir->i_op->mknod)
+               return -EPERM;
+
+       return dir->i_op->mknod(dir, dentry,
+                               S_IFCHR | WHITEOUT_MODE, WHITEOUT_DEV);
+}
+EXPORT_SYMBOL(vfs_whiteout);
+
 int readlink_copy(char __user *buffer, int buflen, const char *link)
 {
        int len = PTR_ERR(link);