BASH PATCH REPORT ================= Bash-Release: 4.3 Patch-ID: bash43-033 Bug-Reported-by: mickael9@gmail.com, Jan Rome 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 # 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_ */