ext4: support RENAME_WHITEOUT

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

diff --git a/fs/namei.c b/fs/namei.c
index d20191c0ebf5693a9fc172e9888f71a77f2b6a02..42df664e95e54a2148093c14fe1f1ce43b909f33 100644 (file)
--- a/fs/namei.c
+++ b/fs/namei.c
@@ -4209,12 +4209,16 @@ 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)) {