LU-8258 nodemap: fix userspace address access in proc code

[fs/lustre-release.git] / lustre / ptlrpc / nodemap_lproc.c

diff --git a/lustre/ptlrpc/nodemap_lproc.c b/lustre/ptlrpc/nodemap_lproc.c
index f9692e3..305f95b 100644 (file)
--- a/lustre/ptlrpc/nodemap_lproc.c
+++ b/lustre/ptlrpc/nodemap_lproc.c
@@ -210,15 +210,32 @@ nodemap_fileset_seq_write(struct file *file,
                                      size_t count, loff_t *off)
 {
        struct seq_file *m = file->private_data;
+       char *nm_fileset;
        int rc = 0;
+       ENTRY;
 
-       if (count > 0)
-               rc = nodemap_set_fileset(m->private, buffer);
+       if (count == 0)
+               RETURN(0);
+
+       if (count > PATH_MAX)
+               RETURN(-EINVAL);
+
+       OBD_ALLOC(nm_fileset, count);
+       if (nm_fileset == NULL)
+               RETURN(-ENOMEM);
 
+       if (copy_from_user(nm_fileset, buffer, count))
+               GOTO(out, rc = -EFAULT);
+
+       rc = nodemap_set_fileset(m->private, nm_fileset);
        if (rc != 0)
-               return -EINVAL;
+               GOTO(out, rc = -EINVAL);
 
-       return count;
+       rc = count;
+out:
+       OBD_FREE(nm_fileset, count);
+
+       return rc;
 }
 LPROC_SEQ_FOPS(nodemap_fileset);