[PATCH] NULL dereference on EOF in heredoc with history on

[Lubomir Rintel]

Configuration Information [Automatically generated, do not change]:
Machine: i386
OS: linux-gnu
Compiler: gcc
Compilation CFLAGS:  -DPROGRAM='bash' -DCONF_HOSTTYPE='i386' 
-DCONF_OSTYPE='linux-gnu' -DCONF_MACHTYPE='i386-redhat-linux-gnu' 
-DCONF_VENDOR='redhat' -DLOCALEDIR='/usr/share/locale' -DPACKAGE='bash' -DSHELL 
-DHAVE_CONFIG_H   -I.  -I. -I./include -I./lib  -D_GNU_SOURCE 
-D_LARGEFILE_SOURCE -D_FILE_OFFSET_BITS=64 -O2 -g -pipe -Wall 
-Wp,-D_FORTIFY_SOURCE=2 -fexceptions -fstack-protector 
--param=ssp-buffer-size=4 -m32 -march=i586 -mtune=generic 
-fasynchronous-unwind-tables
uname output: Linux bimbo.lan 2.6.29-0.237.rc7.git4.fc11.i586 #1 SMP Wed Mar 11 
18:55:21 EDT 2009 i686 i686 i386 GNU/Linux
Machine Type: i386-redhat-linux-gnu

Bash Version: 4.0
Patch Level: 10
Release Status: release

Description:
        If the heredoc input is terminted with end-of-file by pressing ^D
        while history is on, bash enters an infinite loop (due to NULL
        dereference along with a rather sick SIGSEGV handling, which will
        probably be subject to a subsequent patch).

Repeat-By:
        A simple test case is attached. Here's how to reproduce the problem
        in an interactive shell session:

        $ set -o history
        $ true <<DEGE
        > ^D
        ... (looping)

Fix:

diff -urp bash-4.0.orig/parse.y bash-4.0/parse.y
--- bash-4.0.orig/parse.y       2009-03-21 16:52:00.937619544 +0100
+++ bash-4.0/parse.y    2009-03-21 16:54:12.990620212 +0100
@@ -1879,7 +1879,7 @@ read_secondary_line (remove_quoted_newli
     prompt_again ();
   ret = read_a_line (remove_quoted_newline);
 #if defined (HISTORY)
-  if (remember_on_history && (parser_state & PST_HEREDOC))
+  if (ret && remember_on_history && (parser_state & PST_HEREDOC))
     {
       /* To make adding the the here-document body right, we need to rely
         on history_delimiting_chars() returning \n for the first line of
diff -urp bash-4.0.orig/tests/heredoc.right bash-4.0/tests/heredoc.right
--- bash-4.0.orig/tests/heredoc.right   2009-02-19 21:25:53.000000000 +0100
+++ bash-4.0/tests/heredoc.right        2009-03-21 16:57:29.827625342 +0100
@@ -58,6 +58,7 @@ qux
 
 bar
 qux
-./heredoc.tests: line 96: warning: here-document at line 94 delimited by 
end-of-file (wanted `EOF')
+OK: unterminated heredoc spanning end-of-file dealt with correctly
+./heredoc.tests: line 107: warning: here-document at line 105 delimited by 
end-of-file (wanted `EOF')
 hi
 there
diff -urp bash-4.0.orig/tests/heredoc.tests bash-4.0/tests/heredoc.tests
--- bash-4.0.orig/tests/heredoc.tests   2009-02-19 21:25:45.000000000 +0100
+++ bash-4.0/tests/heredoc.tests        2009-03-21 16:57:21.024630685 +0100
@@ -88,6 +88,17 @@ ${THIS_SH} -c 'type fff'
 
 ${THIS_SH} ./heredoc1.sub
 
+# If the above doesn't finish in 4 seconds, then we're
+# almost certainly stuck in an infinite loop
+
+echo 'true <<EOF' |${THIS_SH} -i >/dev/null 2>&1 &
+PID=$!
+sleep 4
+kill -KILL $! 2>/dev/null &&
+  echo 'FAIL: unterminated heredoc spanning end-of-file probably stuck in an 
endless loop' ||
+  echo 'OK: unterminated heredoc spanning end-of-file dealt with correctly'
+wait 2>/dev/null
+
 # check that end of file delimits a here-document
 # THIS MUST BE LAST!
 
-- 
Lubomir Rintel <lkundrak@v3.sk>