ash: fix a case where we close wrong descriptor; add debug hack for that

1 files changed, 13 insertions, 3 deletions

diff --git a/shell/ash.c b/shell/ash.c
index a799cb1a6..13efbbb87 100644
--- a/shell/ash.c
+++ b/shell/ash.c
@@ -260,6 +260,12 @@ static void trace_printf(const char *fmt, ...);
 static void trace_vprintf(const char *fmt, va_list va);
 # define TRACE(param)    trace_printf param
 # define TRACEV(param)   trace_vprintf param
+# define close(f) do { \
+        int dfd = (f); \
+        if (close(dfd) < 0) \
+                bb_error_msg("bug on %d: closing %d(%x)", \
+                        __LINE__, dfd dfd); \
+} while (0)
 #else
 # define TRACE(param)
 # define TRACEV(param)
@@ -5142,7 +5148,9 @@ redirect(union node *redir, int flags)
                 if (newfd < 0) {
                         /* NTOFD/NFROMFD: copy redir->ndup.dupfd to fd */
                         if (redir->ndup.dupfd < 0) { /* "fd>&-" */
-                                close(fd);
+                                /* Don't want to trigger debugging */
+                                if (fd != -1)
+                                        close(fd);
                         } else {
                                 copyfd(redir->ndup.dupfd, fd | COPYFD_EXACT);
                         }
@@ -5195,7 +5203,7 @@ popredir(int drop, int restore)
                                 /*close(fd);*/
                                 copyfd(copy, fd | COPYFD_EXACT);
                         }
-                        close(copy);
+                        close(copy & ~COPYFD_RESTORE);
                 }
         }
         redirlist = rp->next;
@@ -8416,7 +8424,9 @@ evalpipe(union node *n, int flags)
                 if (prevfd >= 0)
                         close(prevfd);
                 prevfd = pip[0];
-                close(pip[1]);
+                /* Don't want to trigger debugging */
+                if (pip[1] != -1)
+                        close(pip[1]);
         }
         if (n->npipe.pipe_backgnd == 0) {
                 exitstatus = waitforjob(jp);