From ddb19f4a310205fd5e25bd4c60544612b34c44f4 Mon Sep 17 00:00:00 2001
From: Chet Ramey <chet.ramey@case.edu>
Date: Mon, 25 Nov 2019 00:43:03 +0100
Subject: Bash-4.3 patch 48

If a malicious user can inject a value of $SHELLOPTS containing `xtrace'
and a value for $PS4 that includes a command substitution into a shell
running as root, bash will expand the command substitution as part of
expanding $PS4 when it executes a traced command.

Change-Id: I89582f14a979f733b3504cc456ce671621825680
---
 patchlevel.h | 2 +-
 variables.c  | 6 +++++-
 2 files changed, 6 insertions(+), 2 deletions(-)

diff --git a/patchlevel.h b/patchlevel.h
index d243f2d..a5241c6 100644
--- a/patchlevel.h
+++ b/patchlevel.h
@@ -25,6 +25,6 @@
    regexp `^#define[ 	]*PATCHLEVEL', since that's what support/mkversion.sh
    looks for to find the patch level (for the sccs version string). */
 
-#define PATCHLEVEL 47
+#define PATCHLEVEL 48
 
 #endif /* _PATCHLEVEL_H_ */
diff --git a/variables.c b/variables.c
index f39eb64..f816ffe 100644
--- a/variables.c
+++ b/variables.c
@@ -495,7 +495,11 @@ initialize_shell_variables (env, privmode)
 #endif
       set_if_not ("PS2", secondary_prompt);
     }
-  set_if_not ("PS4", "+ ");
+
+  if (current_user.euid == 0)
+    bind_variable ("PS4", "+ ", 0);
+  else
+    set_if_not ("PS4", "+ ");
 
   /* Don't allow IFS to be imported from the environment. */
   temp_var = bind_variable ("IFS", " \t\n", 0);
-- 
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