BASH PATCH REPORT
=================
Bash-Release: 4.3
Patch-ID: bash43-033
Bug-Reported-by: mickael9@gmail.com, Jan Rome <jan.rome@gmail.com>
Bug-Reference-ID: <20140907224046.382ED3610CC@mickael-laptop.localdomain>,
<540D661D.50908@gmail.com>
Bug-Reference-URL: http://lists.gnu.org/archive/html/bug-bash/2014-09/msg00029.html
http://lists.gnu.org/archive/html/bug-bash/2014-09/msg00030.html
Bug-Description:
Bash does not clean up the terminal state in all cases where bash or
readline modifies it and bash is subsequently terminated by a fatal signal.
This happens when the `read' builtin modifies the terminal settings, both
when readline is active and when it is not. It occurs most often when a script
installs a trap that exits on a signal without re-sending the signal to itself.
Patch (apply with `patch -p0'):
--- a/shell.c
+++ b/shell.c
@@ -73,6 +73,7 @@
#endif
#if defined (READLINE)
+# include <readline/readline.h>
# include "bashline.h"
#endif
@@ -909,6 +910,14 @@ exit_shell (s)
fflush (stdout); /* XXX */
fflush (stderr);
+ /* Clean up the terminal if we are in a state where it's been modified. */
+#if defined (READLINE)
+ if (RL_ISSTATE (RL_STATE_TERMPREPPED) && rl_deprep_term_function)
+ (*rl_deprep_term_function) ();
+#endif
+ if (read_tty_modified ())
+ read_tty_cleanup ();
+
/* Do trap[0] if defined. Allow it to override the exit status
passed to us. */
if (signal_is_trapped (0))
--- a/builtins/read.def
+++ b/builtins/read.def
@@ -140,10 +140,12 @@ static void reset_alarm __P((void));
procenv_t alrmbuf;
int sigalrm_seen;
-static int reading;
+static int reading, tty_modified;
static SigHandler *old_alrm;
static unsigned char delim;
+static struct ttsave termsave;
+
/* In all cases, SIGALRM just sets a flag that we check periodically. This
avoids problems with the semi-tricky stuff we do with the xfree of
input_string at the top of the unwind-protect list (see below). */
@@ -188,7 +190,6 @@ read_builtin (list)
struct stat tsb;
SHELL_VAR *var;
TTYSTRUCT ttattrs, ttset;
- struct ttsave termsave;
#if defined (ARRAY_VARS)
WORD_LIST *alist;
#endif
@@ -221,7 +222,7 @@ read_builtin (list)
USE_VAR(ps2);
USE_VAR(lastsig);
- sigalrm_seen = reading = 0;
+ sigalrm_seen = reading = tty_modified = 0;
i = 0; /* Index into the string that we are reading. */
raw = edit = 0; /* Not reading raw input by default. */
@@ -438,6 +439,8 @@ read_builtin (list)
retval = 128+SIGALRM;
goto assign_vars;
}
+ if (interactive_shell == 0)
+ initialize_terminating_signals ();
old_alrm = set_signal_handler (SIGALRM, sigalrm);
add_unwind_protect (reset_alarm, (char *)NULL);
#if defined (READLINE)
@@ -482,7 +485,10 @@ read_builtin (list)
i = silent ? ttfd_cbreak (fd, &ttset) : ttfd_onechar (fd, &ttset);
if (i < 0)
sh_ttyerror (1);
+ tty_modified = 1;
add_unwind_protect ((Function *)ttyrestore, (char *)&termsave);
+ if (interactive_shell == 0)
+ initialize_terminating_signals ();
}
}
else if (silent) /* turn off echo but leave term in canonical mode */
@@ -497,7 +503,10 @@ read_builtin (list)
if (i < 0)
sh_ttyerror (1);
+ tty_modified = 1;
add_unwind_protect ((Function *)ttyrestore, (char *)&termsave);
+ if (interactive_shell == 0)
+ initialize_terminating_signals ();
}
/* This *must* be the top unwind-protect on the stack, so the manipulation
@@ -588,6 +597,8 @@ read_builtin (list)
}
else
lastsig = 0;
+ if (terminating_signal && tty_modified)
+ ttyrestore (&termsave); /* fix terminal before exiting */
CHECK_TERMSIG;
eof = 1;
break;
@@ -978,6 +989,20 @@ ttyrestore (ttp)
struct ttsave *ttp;
{
ttsetattr (ttp->fd, ttp->attrs);
+ tty_modified = 0;
+}
+
+void
+read_tty_cleanup ()
+{
+ if (tty_modified)
+ ttyrestore (&termsave);
+}
+
+int
+read_tty_modified ()
+{
+ return (tty_modified);
}
#if defined (READLINE)
--- a/builtins/common.h
+++ b/builtins/common.h
@@ -122,6 +122,10 @@ extern void bash_logout __P((void));
/* Functions from getopts.def */
extern void getopts_reset __P((int));
+/* Functions from read.def */
+extern void read_tty_cleanup __P((void));
+extern int read_tty_modified __P((void));
+
/* Functions from set.def */
extern int minus_o_option_value __P((char *));
extern void list_minus_o_opts __P((int, int));
--- a/bashline.c
+++ b/bashline.c
@@ -202,6 +202,7 @@ extern int current_command_line_count, s
extern int last_command_exit_value;
extern int array_needs_making;
extern int posixly_correct, no_symbolic_links;
+extern int sigalrm_seen;
extern char *current_prompt_string, *ps1_prompt;
extern STRING_INT_ALIST word_token_alist[];
extern sh_builtin_func_t *last_shell_builtin, *this_shell_builtin;
@@ -4208,8 +4209,9 @@ bash_event_hook ()
{
/* If we're going to longjmp to top_level, make sure we clean up readline.
check_signals will call QUIT, which will eventually longjmp to top_level,
- calling run_interrupt_trap along the way. */
- if (interrupt_state)
+ calling run_interrupt_trap along the way. The check for sigalrm_seen is
+ to clean up the read builtin's state. */
+ if (terminating_signal || interrupt_state || sigalrm_seen)
rl_cleanup_after_signal ();
bashline_reset_event_hook ();
check_signals_and_traps (); /* XXX */
--- a/sig.c
+++ b/sig.c
@@ -532,8 +532,10 @@ termsig_sighandler (sig)
#if defined (READLINE)
/* Set the event hook so readline will call it after the signal handlers
finish executing, so if this interrupted character input we can get
- quick response. */
- if (interactive_shell && interactive && no_line_editing == 0)
+ quick response. If readline is active or has modified the terminal we
+ need to set this no matter what the signal is, though the check for
+ RL_STATE_TERMPREPPED is possibly redundant. */
+ if (RL_ISSTATE (RL_STATE_SIGHANDLER) || RL_ISSTATE (RL_STATE_TERMPREPPED))
bashline_set_event_hook ();
#endif
--- 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 32
+#define PATCHLEVEL 33
#endif /* _PATCHLEVEL_H_ */