CVE-2017-2619: s3: smbd: Move special handling of symlink errno's into a utility...

BUG: https://bugzilla.samba.org/show_bug.cgi?id=12496

Signed-off-by: Jeremy Allison <jra@samba.org>
Reviewed-by: Uri Simchoni <uri@samba.org>

diff --git a/source3/smbd/open.c b/source3/smbd/open.c
index 11f16da13a99ebb439681f96ca1078fcf4eda51c..ddd37054be0255074063b3412fde15dd6c7b2d43 100644 (file)
--- a/source3/smbd/open.c
+++ b/source3/smbd/open.c
@@ -363,6 +363,31 @@ static NTSTATUS check_base_file_access(struct connection_struct *conn,
                                        access_mask);
 }
 
+/****************************************************************************
+ Handle differing symlink errno's
+****************************************************************************/
+
+static int link_errno_convert(int err)
+{
+#if defined(ENOTSUP) && defined(OSF1)
+       /* handle special Tru64 errno */
+       if (err == ENOTSUP) {
+               err = ELOOP;
+       }
+#endif /* ENOTSUP */
+#ifdef EFTYPE
+       /* fix broken NetBSD errno */
+       if (err == EFTYPE) {
+               err = ELOOP;
+       }
+#endif /* EFTYPE */
+       /* fix broken FreeBSD errno */
+       if (err == EMLINK) {
+               err = ELOOP;
+       }
+       return err;
+}
+
 /****************************************************************************
  fd support routines - attempt to do a dos_open.
 ****************************************************************************/
@@ -386,23 +411,7 @@ NTSTATUS fd_open(struct connection_struct *conn,
 
        fsp->fh->fd = SMB_VFS_OPEN(conn, smb_fname, fsp, flags, mode);
        if (fsp->fh->fd == -1) {
-               int posix_errno = errno;
-#if defined(ENOTSUP) && defined(OSF1)
-               /* handle special Tru64 errno */
-               if (errno == ENOTSUP) {
-                       posix_errno = ELOOP;
-               }
-#endif /* ENOTSUP */
-#ifdef EFTYPE
-               /* fix broken NetBSD errno */
-               if (errno == EFTYPE) {
-                       posix_errno = ELOOP;
-               }
-#endif /* EFTYPE */
-               /* fix broken FreeBSD errno */
-               if (errno == EMLINK) {
-                       posix_errno = ELOOP;
-               }
+               int posix_errno = link_errno_convert(errno);
                status = map_nt_error_from_unix(posix_errno);
                if (errno == EMFILE) {
                        static time_t last_warned = 0L;