BASH PATCH REPORT
=================
Bash-Release: 5.2
Patch-ID: bash52-015
Bug-Reported-by: Frode Nordahl <frode.nordahl@canonical.com>
Bug-Reference-ID: <20221119070714.351759-1-frode.nordahl@canonical.com>
Bug-Reference-URL: https://lists.gnu.org/archive/html/bug-bash/2022-11/msg00078.html
Bug-Description:
There are several cases where bash is too aggressive when optimizing out forks
in subshells. For example, `eval' and traps should never be optimized.
Patch (apply with `patch -p0'):
*** ../bash-5.2-patched/builtins/common.h 2022-11-23 17:09:18.000000000 -0500
--- builtins/common.h 2022-11-19 18:03:59.000000000 -0500
***************
*** 52,55 ****
--- 52,56 ----
#define SEVAL_ONECMD 0x100 /* only allow a single command */
#define SEVAL_NOHISTEXP 0x200 /* inhibit history expansion */
+ #define SEVAL_NOOPTIMIZE 0x400 /* don't try to set optimization flags */
/* Flags for describe_command, shared between type.def and command.def */
*** ../bash-5.2-patched/builtins/evalstring.c 2022-11-05 17:27:44.000000000 -0400
--- builtins/evalstring.c 2022-11-19 18:23:21.000000000 -0500
***************
*** 133,138 ****
(command->value.Connection->connector == AND_AND || command->value.Connection->connector == OR_OR || command->value.Connection->connector == ';') &&
(command->value.Connection->second->flags & CMD_TRY_OPTIMIZING) &&
! ((startup_state == 2 && should_suppress_fork (command->value.Connection->second)) ||
! ((subshell_environment & SUBSHELL_PAREN) && should_optimize_fork (command->value.Connection->second, 0))))
{
command->value.Connection->second->flags |= CMD_NO_FORK;
--- 133,138 ----
(command->value.Connection->connector == AND_AND || command->value.Connection->connector == OR_OR || command->value.Connection->connector == ';') &&
(command->value.Connection->second->flags & CMD_TRY_OPTIMIZING) &&
! (should_suppress_fork (command->value.Connection->second) ||
! ((subshell_environment & SUBSHELL_PAREN) && should_optimize_fork (command->value.Connection->second, 0))))
{
command->value.Connection->second->flags |= CMD_NO_FORK;
***************
*** 291,294 ****
--- 291,295 ----
(flags & SEVAL_RESETLINE) -> reset line_number to 1
(flags & SEVAL_NOHISTEXP) -> history_expansion_inhibited -> 1
+ (flags & SEVAL_NOOPTIMIZE) -> don't try to turn on optimizing flags
*/
***************
*** 503,507 ****
series of connection commands is
command->value.Connection->second. */
! else if (command->type == cm_connection && can_optimize_connection (command))
{
command->value.Connection->second->flags |= CMD_TRY_OPTIMIZING;
--- 504,510 ----
series of connection commands is
command->value.Connection->second. */
! else if (command->type == cm_connection &&
! (flags & SEVAL_NOOPTIMIZE) == 0 &&
! can_optimize_connection (command))
{
command->value.Connection->second->flags |= CMD_TRY_OPTIMIZING;
*** ../bash-5.2-patched/builtins/eval.def 2016-01-25 13:28:37.000000000 -0500
--- builtins/eval.def 2022-11-19 18:04:25.000000000 -0500
***************
*** 54,57 ****
list = loptend; /* skip over possible `--' */
! return (list ? evalstring (string_list (list), "eval", SEVAL_NOHIST) : EXECUTION_SUCCESS);
}
--- 54,57 ----
list = loptend; /* skip over possible `--' */
! return (list ? evalstring (string_list (list), "eval", SEVAL_NOHIST|SEVAL_NOOPTIMIZE) : EXECUTION_SUCCESS);
}
*** ../bash-5.2-patched/trap.c 2022-08-10 08:59:45.000000000 -0400
--- trap.c 2022-12-12 10:57:51.000000000 -0500
***************
*** 305,308 ****
--- 305,309 ----
volatile int save_return_catch_flag, function_code;
procenv_t save_return_catch;
+ char *trap_command, *old_trap;
#if defined (ARRAY_VARS)
ARRAY *ps;
***************
*** 420,423 ****
--- 421,427 ----
else
{
+ old_trap = trap_list[sig];
+ trap_command = savestring (old_trap);
+
save_parser_state (&pstate);
save_subst_varlist = subst_assign_varlist;
***************
*** 442,446 ****
if (function_code == 0)
! x = parse_and_execute (savestring (trap_list[sig]), "trap", SEVAL_NONINT|SEVAL_NOHIST|SEVAL_RESETLINE);
else
{
--- 446,451 ----
if (function_code == 0)
! /* XXX is x always last_command_exit_value? */
! x = parse_and_execute (trap_command, "trap", SEVAL_NONINT|SEVAL_NOHIST|SEVAL_RESETLINE|SEVAL_NOOPTIMIZE);
else
{
***************
*** 1003,1007 ****
{
reset_parser ();
! parse_and_execute (trap_command, "exit trap", SEVAL_NONINT|SEVAL_NOHIST|SEVAL_RESETLINE);
}
else if (code == ERREXIT)
--- 1008,1012 ----
{
reset_parser ();
! parse_and_execute (trap_command, "exit trap", SEVAL_NONINT|SEVAL_NOHIST|SEVAL_RESETLINE|SEVAL_NOOPTIMIZE);
}
else if (code == ERREXIT)
***************
*** 1110,1114 ****
}
! flags = SEVAL_NONINT|SEVAL_NOHIST;
if (sig != DEBUG_TRAP && sig != RETURN_TRAP && sig != ERROR_TRAP)
flags |= SEVAL_RESETLINE;
--- 1115,1119 ----
}
! flags = SEVAL_NONINT|SEVAL_NOHIST|SEVAL_NOOPTIMIZE;
if (sig != DEBUG_TRAP && sig != RETURN_TRAP && sig != ERROR_TRAP)
flags |= SEVAL_RESETLINE;
*** ../bash-5.2-patched/parse.y 2022-11-23 17:09:18.000000000 -0500
--- parse.y 2022-11-19 18:15:34.000000000 -0500
***************
*** 2828,2832 ****
last_lastarg = savestring (last_lastarg);
! parse_and_execute (savestring (command), vname, SEVAL_NONINT|SEVAL_NOHIST);
restore_parser_state (&ps);
--- 2844,2848 ----
last_lastarg = savestring (last_lastarg);
! parse_and_execute (savestring (command), vname, SEVAL_NONINT|SEVAL_NOHIST|SEVAL_NOOPTIMIZE);
restore_parser_state (&ps);
*** ../bash-5.2-patched/jobs.c 2022-07-18 10:19:56.000000000 -0400
--- jobs.c 2022-11-19 18:10:24.000000000 -0500
***************
*** 4221,4225 ****
for (i = 0; i < nchild; i++)
{
! parse_and_execute (savestring (trap_command), "trap", SEVAL_NOHIST|SEVAL_RESETLINE);
}
--- 4243,4247 ----
for (i = 0; i < nchild; i++)
{
! parse_and_execute (savestring (trap_command), "trap", SEVAL_NOHIST|SEVAL_RESETLINE|SEVAL_NOOPTIMIZE);
}
*** ../bash-5.2-patched/y.tab.c 2022-11-23 17:09:18.000000000 -0500
--- y.tab.c 2022-11-23 17:21:17.000000000 -0500
***************
*** 5139,5143 ****
last_lastarg = savestring (last_lastarg);
! parse_and_execute (savestring (command), vname, SEVAL_NONINT|SEVAL_NOHIST);
restore_parser_state (&ps);
--- 5154,5158 ----
last_lastarg = savestring (last_lastarg);
! parse_and_execute (savestring (command), vname, SEVAL_NONINT|SEVAL_NOHIST|SEVAL_NOOPTIMIZE);
restore_parser_state (&ps);
*** ../bash-5.2-patched/execute_cmd.c 2022-11-05 17:27:41.000000000 -0400
--- execute_cmd.c 2022-11-22 17:09:38.000000000 -0500
***************
*** 1655,1659 ****
and set CMD_TRY_OPTIMIZING for simple commands on the right side of an
and-or or `;' list to test for optimizing forks when they are executed. */
! if (user_subshell && command->type == cm_subshell)
optimize_subshell_command (command->value.Subshell->command);
--- 1665,1670 ----
and set CMD_TRY_OPTIMIZING for simple commands on the right side of an
and-or or `;' list to test for optimizing forks when they are executed. */
! if (user_subshell && command->type == cm_subshell &&
! (command->flags & (CMD_TIME_PIPELINE|CMD_INVERT_RETURN)) == 0)
optimize_subshell_command (command->value.Subshell->command);
*** ../bash-5.2/patchlevel.h 2020-06-22 14:51:03.000000000 -0400
--- patchlevel.h 2020-10-01 11:01:28.000000000 -0400
***************
*** 26,30 ****
looks for to find the patch level (for the sccs version string). */
! #define PATCHLEVEL 14
#endif /* _PATCHLEVEL_H_ */
--- 26,30 ----
looks for to find the patch level (for the sccs version string). */
! #define PATCHLEVEL 15
#endif /* _PATCHLEVEL_H_ */
