Don't let a failing mparse_open() clobber the filename pointer;

fixes error message content and a use after free
for .so with non-existent target when -Wall or -Tlint is given.

diff --git a/usr.bin/mandoc/read.c b/usr.bin/mandoc/read.c
index d07926a..1ddd57f 100644 (file)
--- a/usr.bin/mandoc/read.c
+++ b/usr.bin/mandoc/read.c
@@ -1,4 +1,4 @@
-/*     $OpenBSD: read.c,v 1.87 2015/01/20 21:12:46 schwarze Exp $ */
+/*     $OpenBSD: read.c,v 1.88 2015/01/22 19:26:16 schwarze Exp $ */
 /*
  * Copyright (c) 2008, 2009, 2010, 2011 Kristaps Dzonsons <kristaps@bsd.lv>
  * Copyright (c) 2010-2015 Ingo Schwarze <schwarze@openbsd.org>
@@ -302,6 +302,7 @@ mparse_buf_r(struct mparse *curp, struct buf blk, size_t i, int start)
 {
        const struct tbl_span   *span;
        struct buf       ln;
+       const char      *save_file;
        char            *cp;
        size_t           pos; /* byte number in the ln buffer */
        enum rofferr     rr;
@@ -517,11 +518,14 @@ rerun:
                         */
                        if (curp->secondary)
                                curp->secondary->sz -= pos + 1;
+                       save_file = curp->file;
                        save_child = curp->child;
                        if (mparse_open(curp, &fd, ln.buf + of) ==
-                           MANDOCLEVEL_OK)
+                           MANDOCLEVEL_OK) {
                                mparse_readfd(curp, fd, ln.buf + of);
-                       else {
+                               curp->file = save_file;
+                       } else {
+                               curp->file = save_file;
                                mandoc_vmsg(MANDOCERR_SO_FAIL,
                                    curp, curp->line, pos,
                                    ".so %s", ln.buf + of);