2019-01-01 07:01:51 +01:00
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/* Copyright (C) 2016-2019 Free Software Foundation, Inc.
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2016-08-09 21:16:20 +02:00
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This file is part of GDB.
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This program is free software; you can redistribute it and/or modify
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it under the terms of the GNU General Public License as published by
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the Free Software Foundation; either version 3 of the License, or
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(at your option) any later version.
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This program is distributed in the hope that it will be useful,
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but WITHOUT ANY WARRANTY; without even the implied warranty of
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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GNU General Public License for more details.
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You should have received a copy of the GNU General Public License
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along with this program. If not, see <http://www.gnu.org/licenses/>. */
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#include "common-defs.h"
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#include "signals-state-save-restore.h"
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Add RAII class for blocking gdb signals
This adds configury support and an RAII class that can be used to
temporarily block signals that are used by gdb. (This class is not
used in this patch, but it split out for easier review.)
The idea of this patch is that these signals should only be delivered
to the main thread. So, when creating a background thread, they are
temporarily blocked; the blocked state is inherited by the new thread.
The sigprocmask man page says:
The use of sigprocmask() is unspecified in a multithreaded
process; see pthread_sigmask(3).
This patch changes gdb to use pthread_sigmask when appropriate, by
introducing a convenience define.
I've updated gdbserver as well, because I had to touch gdbsupport, and
because the threading patches will make it link against the thread
library.
I chose not to touch the NTO code, because I don't know anything about
that platform and because I cannot test it.
Finally, this modifies an existing spot in the Guile layer to use the
new facility.
gdb/ChangeLog
2019-11-26 Tom Tromey <tom@tromey.com>
* gdbsupport/signals-state-save-restore.c (original_signal_mask):
Remove comment.
(save_original_signals_state, restore_original_signals_state): Use
gdb_sigmask.
* linux-nat.c (block_child_signals, restore_child_signals_mask)
(_initialize_linux_nat): Use gdb_sigmask.
* guile/guile.c (_initialize_guile): Use block_signals.
* Makefile.in (HFILES_NO_SRCDIR): Add gdb-sigmask.h.
* gdbsupport/gdb-sigmask.h: New file.
* event-top.c (async_sigtstp_handler): Use gdb_sigmask.
* cp-support.c (gdb_demangle): Use gdb_sigmask.
* gdbsupport/common.m4 (GDB_AC_COMMON): Check for
pthread_sigmask.
* configure, config.in: Rebuild.
* gdbsupport/block-signals.h: New file.
gdb/gdbserver/ChangeLog
2019-11-26 Tom Tromey <tom@tromey.com>
* remote-utils.c (block_unblock_async_io): Use gdb_sigmask.
* linux-low.c (linux_wait_for_event_filtered, linux_async): Use
gdb_sigmask.
* configure, config.in: Rebuild.
Change-Id: If3f37dc57dd859c226e9e4d79458a0514746e8c6
2019-09-29 16:50:15 +02:00
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#include "gdbsupport/gdb-sigmask.h"
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2016-08-09 21:16:20 +02:00
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#include <signal.h>
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/* The original signal actions and mask. */
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#ifdef HAVE_SIGACTION
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static struct sigaction original_signal_actions[NSIG];
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static sigset_t original_signal_mask;
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#endif
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/* See signals-state-save-restore.h. */
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void
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Fix regression: cannot start with LD_PRELOAD=libSegFault.so (PR gdb/18653#c7)
At https://sourceware.org/bugzilla/show_bug.cgi?id=18653#c7, Andrew
reports that the fix for PR gdb/18653 made GDB useless if you preload
libSegFault.so, because GDB internal-errors on startup:
$ LD_PRELOAD=libSegFault.so gdb
src/gdb/common/signals-state-save-restore.c:64: internal-error: unexpected signal handler
A problem internal to GDB has been detected,
further debugging may prove unreliable.
Aborted (core dumped)
$
The internal error comes from the code saving the signal dispositions
inherited from gdb's parent:
(top-gdb) bt
#0 0x000000000056b001 in internal_error(char const*, int, char const*, ...) (file=0xaf5f38 "src/gdb/common/signals-state-save-restore.c", line=64, fmt=0xaf5f18 "unexpected signal handler") at src/gdb/common/errors.c:54
#1 0x00000000005752c9 in save_original_signals_state() () at src/gdb/common/signals-state-save-restore.c:64
#2 0x00000000007425de in captured_main_1(captured_main_args*) (context=0x7fffffffd860)
at src/gdb/main.c:509
#3 0x0000000000743622 in captured_main(void*) (data=0x7fffffffd860) at src/gdb/main.c:1145
During symbol reading, cannot get low and high bounds for subprogram DIE at 24065.
#4 0x00000000007436f9 in gdb_main(captured_main_args*) (args=0x7fffffffd860) at src/gdb/main.c:1171
#5 0x0000000000413acd in main(int, char**) (argc=1, argv=0x7fffffffd968) at src/gdb/gdb.c:32
This commit downgrades the internal error to a warning. You'll get
instead:
~~~
$ LD_PRELOAD=libSegFault.so gdb
warning: Found custom handler for signal 11 (Segmentation fault) preinstalled.
Some signal dispositions inherited from the environment (SIG_DFL/SIG_IGN)
won't be propagated to spawned programs.
GNU gdb (GDB) 8.0.50.20171213-git
Copyright (C) 2017 Free Software Foundation, Inc.
License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html>
This is free software: you are free to change and redistribute it.
There is NO WARRANTY, to the extent permitted by law. Type "show copying"
and "show warranty" for details.
This GDB was configured as "x86_64-pc-linux-gnu".
Type "show configuration" for configuration details.
For bug reporting instructions, please see:
<http://www.gnu.org/software/gdb/bugs/>.
Find the GDB manual and other documentation resources online at:
<http://www.gnu.org/software/gdb/documentation/>.
For help, type "help".
Type "apropos word" to search for commands related to "word"...
(gdb)
~~~
This also moves the location where save_original_signals_state is
called a bit further below (to after option processing), so that "-q"
disables the warning:
~~~
$ LD_PRELOAD=libSegFault.so gdb -q
(gdb)
~~~
New testcase included.
gdb/ChangeLog:
2018-01-05 Pedro Alves <palves@redhat.com>
PR gdb/18653
* common/signals-state-save-restore.c
(save_original_signals_state): New parameter 'quiet'. Warn if we
find a custom handler preinstalled, instead of internal erroring.
But only warn if !quiet.
* common/signals-state-save-restore.h
(save_original_signals_state): New parameter 'quiet'.
* main.c (captured_main_1): Move save_original_signals_state call
after option handling, and pass QUIET.
gdb/gdbserver/ChangeLog:
2018-01-05 Pedro Alves <palves@redhat.com>
PR gdb/18653
* server.c (captured_main): Pass quiet=false to
save_original_signals_state.
gdb/testsuite/ChangeLog:
2018-01-05 Pedro Alves <palves@redhat.com>
PR gdb/18653
* gdb.base/libsegfault.exp: New.
2018-01-05 19:26:18 +01:00
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save_original_signals_state (bool quiet)
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2016-08-09 21:16:20 +02:00
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{
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#ifdef HAVE_SIGACTION
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int i;
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int res;
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Add RAII class for blocking gdb signals
This adds configury support and an RAII class that can be used to
temporarily block signals that are used by gdb. (This class is not
used in this patch, but it split out for easier review.)
The idea of this patch is that these signals should only be delivered
to the main thread. So, when creating a background thread, they are
temporarily blocked; the blocked state is inherited by the new thread.
The sigprocmask man page says:
The use of sigprocmask() is unspecified in a multithreaded
process; see pthread_sigmask(3).
This patch changes gdb to use pthread_sigmask when appropriate, by
introducing a convenience define.
I've updated gdbserver as well, because I had to touch gdbsupport, and
because the threading patches will make it link against the thread
library.
I chose not to touch the NTO code, because I don't know anything about
that platform and because I cannot test it.
Finally, this modifies an existing spot in the Guile layer to use the
new facility.
gdb/ChangeLog
2019-11-26 Tom Tromey <tom@tromey.com>
* gdbsupport/signals-state-save-restore.c (original_signal_mask):
Remove comment.
(save_original_signals_state, restore_original_signals_state): Use
gdb_sigmask.
* linux-nat.c (block_child_signals, restore_child_signals_mask)
(_initialize_linux_nat): Use gdb_sigmask.
* guile/guile.c (_initialize_guile): Use block_signals.
* Makefile.in (HFILES_NO_SRCDIR): Add gdb-sigmask.h.
* gdbsupport/gdb-sigmask.h: New file.
* event-top.c (async_sigtstp_handler): Use gdb_sigmask.
* cp-support.c (gdb_demangle): Use gdb_sigmask.
* gdbsupport/common.m4 (GDB_AC_COMMON): Check for
pthread_sigmask.
* configure, config.in: Rebuild.
* gdbsupport/block-signals.h: New file.
gdb/gdbserver/ChangeLog
2019-11-26 Tom Tromey <tom@tromey.com>
* remote-utils.c (block_unblock_async_io): Use gdb_sigmask.
* linux-low.c (linux_wait_for_event_filtered, linux_async): Use
gdb_sigmask.
* configure, config.in: Rebuild.
Change-Id: If3f37dc57dd859c226e9e4d79458a0514746e8c6
2019-09-29 16:50:15 +02:00
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res = gdb_sigmask (0, NULL, &original_signal_mask);
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2016-08-09 21:16:20 +02:00
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if (res == -1)
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2016-08-10 17:06:57 +02:00
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perror_with_name (("sigprocmask"));
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2016-08-09 21:16:20 +02:00
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Fix regression: cannot start with LD_PRELOAD=libSegFault.so (PR gdb/18653#c7)
At https://sourceware.org/bugzilla/show_bug.cgi?id=18653#c7, Andrew
reports that the fix for PR gdb/18653 made GDB useless if you preload
libSegFault.so, because GDB internal-errors on startup:
$ LD_PRELOAD=libSegFault.so gdb
src/gdb/common/signals-state-save-restore.c:64: internal-error: unexpected signal handler
A problem internal to GDB has been detected,
further debugging may prove unreliable.
Aborted (core dumped)
$
The internal error comes from the code saving the signal dispositions
inherited from gdb's parent:
(top-gdb) bt
#0 0x000000000056b001 in internal_error(char const*, int, char const*, ...) (file=0xaf5f38 "src/gdb/common/signals-state-save-restore.c", line=64, fmt=0xaf5f18 "unexpected signal handler") at src/gdb/common/errors.c:54
#1 0x00000000005752c9 in save_original_signals_state() () at src/gdb/common/signals-state-save-restore.c:64
#2 0x00000000007425de in captured_main_1(captured_main_args*) (context=0x7fffffffd860)
at src/gdb/main.c:509
#3 0x0000000000743622 in captured_main(void*) (data=0x7fffffffd860) at src/gdb/main.c:1145
During symbol reading, cannot get low and high bounds for subprogram DIE at 24065.
#4 0x00000000007436f9 in gdb_main(captured_main_args*) (args=0x7fffffffd860) at src/gdb/main.c:1171
#5 0x0000000000413acd in main(int, char**) (argc=1, argv=0x7fffffffd968) at src/gdb/gdb.c:32
This commit downgrades the internal error to a warning. You'll get
instead:
~~~
$ LD_PRELOAD=libSegFault.so gdb
warning: Found custom handler for signal 11 (Segmentation fault) preinstalled.
Some signal dispositions inherited from the environment (SIG_DFL/SIG_IGN)
won't be propagated to spawned programs.
GNU gdb (GDB) 8.0.50.20171213-git
Copyright (C) 2017 Free Software Foundation, Inc.
License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html>
This is free software: you are free to change and redistribute it.
There is NO WARRANTY, to the extent permitted by law. Type "show copying"
and "show warranty" for details.
This GDB was configured as "x86_64-pc-linux-gnu".
Type "show configuration" for configuration details.
For bug reporting instructions, please see:
<http://www.gnu.org/software/gdb/bugs/>.
Find the GDB manual and other documentation resources online at:
<http://www.gnu.org/software/gdb/documentation/>.
For help, type "help".
Type "apropos word" to search for commands related to "word"...
(gdb)
~~~
This also moves the location where save_original_signals_state is
called a bit further below (to after option processing), so that "-q"
disables the warning:
~~~
$ LD_PRELOAD=libSegFault.so gdb -q
(gdb)
~~~
New testcase included.
gdb/ChangeLog:
2018-01-05 Pedro Alves <palves@redhat.com>
PR gdb/18653
* common/signals-state-save-restore.c
(save_original_signals_state): New parameter 'quiet'. Warn if we
find a custom handler preinstalled, instead of internal erroring.
But only warn if !quiet.
* common/signals-state-save-restore.h
(save_original_signals_state): New parameter 'quiet'.
* main.c (captured_main_1): Move save_original_signals_state call
after option handling, and pass QUIET.
gdb/gdbserver/ChangeLog:
2018-01-05 Pedro Alves <palves@redhat.com>
PR gdb/18653
* server.c (captured_main): Pass quiet=false to
save_original_signals_state.
gdb/testsuite/ChangeLog:
2018-01-05 Pedro Alves <palves@redhat.com>
PR gdb/18653
* gdb.base/libsegfault.exp: New.
2018-01-05 19:26:18 +01:00
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bool found_preinstalled = false;
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2016-08-09 21:16:20 +02:00
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for (i = 1; i < NSIG; i++)
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{
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struct sigaction *oldact = &original_signal_actions[i];
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res = sigaction (i, NULL, oldact);
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if (res == -1 && errno == EINVAL)
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{
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/* Some signal numbers in the range are invalid. */
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continue;
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}
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else if (res == -1)
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2016-08-10 17:06:57 +02:00
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perror_with_name (("sigaction"));
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2016-08-09 21:16:20 +02:00
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/* If we find a custom signal handler already installed, then
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Fix regression: cannot start with LD_PRELOAD=libSegFault.so (PR gdb/18653#c7)
At https://sourceware.org/bugzilla/show_bug.cgi?id=18653#c7, Andrew
reports that the fix for PR gdb/18653 made GDB useless if you preload
libSegFault.so, because GDB internal-errors on startup:
$ LD_PRELOAD=libSegFault.so gdb
src/gdb/common/signals-state-save-restore.c:64: internal-error: unexpected signal handler
A problem internal to GDB has been detected,
further debugging may prove unreliable.
Aborted (core dumped)
$
The internal error comes from the code saving the signal dispositions
inherited from gdb's parent:
(top-gdb) bt
#0 0x000000000056b001 in internal_error(char const*, int, char const*, ...) (file=0xaf5f38 "src/gdb/common/signals-state-save-restore.c", line=64, fmt=0xaf5f18 "unexpected signal handler") at src/gdb/common/errors.c:54
#1 0x00000000005752c9 in save_original_signals_state() () at src/gdb/common/signals-state-save-restore.c:64
#2 0x00000000007425de in captured_main_1(captured_main_args*) (context=0x7fffffffd860)
at src/gdb/main.c:509
#3 0x0000000000743622 in captured_main(void*) (data=0x7fffffffd860) at src/gdb/main.c:1145
During symbol reading, cannot get low and high bounds for subprogram DIE at 24065.
#4 0x00000000007436f9 in gdb_main(captured_main_args*) (args=0x7fffffffd860) at src/gdb/main.c:1171
#5 0x0000000000413acd in main(int, char**) (argc=1, argv=0x7fffffffd968) at src/gdb/gdb.c:32
This commit downgrades the internal error to a warning. You'll get
instead:
~~~
$ LD_PRELOAD=libSegFault.so gdb
warning: Found custom handler for signal 11 (Segmentation fault) preinstalled.
Some signal dispositions inherited from the environment (SIG_DFL/SIG_IGN)
won't be propagated to spawned programs.
GNU gdb (GDB) 8.0.50.20171213-git
Copyright (C) 2017 Free Software Foundation, Inc.
License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html>
This is free software: you are free to change and redistribute it.
There is NO WARRANTY, to the extent permitted by law. Type "show copying"
and "show warranty" for details.
This GDB was configured as "x86_64-pc-linux-gnu".
Type "show configuration" for configuration details.
For bug reporting instructions, please see:
<http://www.gnu.org/software/gdb/bugs/>.
Find the GDB manual and other documentation resources online at:
<http://www.gnu.org/software/gdb/documentation/>.
For help, type "help".
Type "apropos word" to search for commands related to "word"...
(gdb)
~~~
This also moves the location where save_original_signals_state is
called a bit further below (to after option processing), so that "-q"
disables the warning:
~~~
$ LD_PRELOAD=libSegFault.so gdb -q
(gdb)
~~~
New testcase included.
gdb/ChangeLog:
2018-01-05 Pedro Alves <palves@redhat.com>
PR gdb/18653
* common/signals-state-save-restore.c
(save_original_signals_state): New parameter 'quiet'. Warn if we
find a custom handler preinstalled, instead of internal erroring.
But only warn if !quiet.
* common/signals-state-save-restore.h
(save_original_signals_state): New parameter 'quiet'.
* main.c (captured_main_1): Move save_original_signals_state call
after option handling, and pass QUIET.
gdb/gdbserver/ChangeLog:
2018-01-05 Pedro Alves <palves@redhat.com>
PR gdb/18653
* server.c (captured_main): Pass quiet=false to
save_original_signals_state.
gdb/testsuite/ChangeLog:
2018-01-05 Pedro Alves <palves@redhat.com>
PR gdb/18653
* gdb.base/libsegfault.exp: New.
2018-01-05 19:26:18 +01:00
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this function was called too late. This is a warning instead
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of an internal error because this can also happen if you
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LD_PRELOAD a library that installs a signal handler early via
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__attribute__((constructor)), like libSegFault.so. */
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if (!quiet
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&& oldact->sa_handler != SIG_DFL
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&& oldact->sa_handler != SIG_IGN)
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{
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found_preinstalled = true;
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/* Use raw fprintf here because we're being called in early
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2018-01-15 21:03:20 +01:00
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startup, before GDB's filtered streams are created. */
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Fix regression: cannot start with LD_PRELOAD=libSegFault.so (PR gdb/18653#c7)
At https://sourceware.org/bugzilla/show_bug.cgi?id=18653#c7, Andrew
reports that the fix for PR gdb/18653 made GDB useless if you preload
libSegFault.so, because GDB internal-errors on startup:
$ LD_PRELOAD=libSegFault.so gdb
src/gdb/common/signals-state-save-restore.c:64: internal-error: unexpected signal handler
A problem internal to GDB has been detected,
further debugging may prove unreliable.
Aborted (core dumped)
$
The internal error comes from the code saving the signal dispositions
inherited from gdb's parent:
(top-gdb) bt
#0 0x000000000056b001 in internal_error(char const*, int, char const*, ...) (file=0xaf5f38 "src/gdb/common/signals-state-save-restore.c", line=64, fmt=0xaf5f18 "unexpected signal handler") at src/gdb/common/errors.c:54
#1 0x00000000005752c9 in save_original_signals_state() () at src/gdb/common/signals-state-save-restore.c:64
#2 0x00000000007425de in captured_main_1(captured_main_args*) (context=0x7fffffffd860)
at src/gdb/main.c:509
#3 0x0000000000743622 in captured_main(void*) (data=0x7fffffffd860) at src/gdb/main.c:1145
During symbol reading, cannot get low and high bounds for subprogram DIE at 24065.
#4 0x00000000007436f9 in gdb_main(captured_main_args*) (args=0x7fffffffd860) at src/gdb/main.c:1171
#5 0x0000000000413acd in main(int, char**) (argc=1, argv=0x7fffffffd968) at src/gdb/gdb.c:32
This commit downgrades the internal error to a warning. You'll get
instead:
~~~
$ LD_PRELOAD=libSegFault.so gdb
warning: Found custom handler for signal 11 (Segmentation fault) preinstalled.
Some signal dispositions inherited from the environment (SIG_DFL/SIG_IGN)
won't be propagated to spawned programs.
GNU gdb (GDB) 8.0.50.20171213-git
Copyright (C) 2017 Free Software Foundation, Inc.
License GPLv3+: GNU GPL version 3 or later <http://gnu.org/licenses/gpl.html>
This is free software: you are free to change and redistribute it.
There is NO WARRANTY, to the extent permitted by law. Type "show copying"
and "show warranty" for details.
This GDB was configured as "x86_64-pc-linux-gnu".
Type "show configuration" for configuration details.
For bug reporting instructions, please see:
<http://www.gnu.org/software/gdb/bugs/>.
Find the GDB manual and other documentation resources online at:
<http://www.gnu.org/software/gdb/documentation/>.
For help, type "help".
Type "apropos word" to search for commands related to "word"...
(gdb)
~~~
This also moves the location where save_original_signals_state is
called a bit further below (to after option processing), so that "-q"
disables the warning:
~~~
$ LD_PRELOAD=libSegFault.so gdb -q
(gdb)
~~~
New testcase included.
gdb/ChangeLog:
2018-01-05 Pedro Alves <palves@redhat.com>
PR gdb/18653
* common/signals-state-save-restore.c
(save_original_signals_state): New parameter 'quiet'. Warn if we
find a custom handler preinstalled, instead of internal erroring.
But only warn if !quiet.
* common/signals-state-save-restore.h
(save_original_signals_state): New parameter 'quiet'.
* main.c (captured_main_1): Move save_original_signals_state call
after option handling, and pass QUIET.
gdb/gdbserver/ChangeLog:
2018-01-05 Pedro Alves <palves@redhat.com>
PR gdb/18653
* server.c (captured_main): Pass quiet=false to
save_original_signals_state.
gdb/testsuite/ChangeLog:
2018-01-05 Pedro Alves <palves@redhat.com>
PR gdb/18653
* gdb.base/libsegfault.exp: New.
2018-01-05 19:26:18 +01:00
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fprintf (stderr,
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_("warning: Found custom handler for signal "
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"%d (%s) preinstalled.\n"), i,
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strsignal (i));
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}
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}
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|
|
if (found_preinstalled)
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|
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|
{
|
|
|
|
fprintf (stderr, _("\
|
|
|
|
Some signal dispositions inherited from the environment (SIG_DFL/SIG_IGN)\n\
|
|
|
|
won't be propagated to spawned programs.\n"));
|
2016-08-09 21:16:20 +02:00
|
|
|
}
|
|
|
|
#endif
|
|
|
|
}
|
|
|
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|
|
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|
/* See signals-state-save-restore.h. */
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|
|
|
|
|
|
|
void
|
|
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|
restore_original_signals_state (void)
|
|
|
|
{
|
|
|
|
#ifdef HAVE_SIGACTION
|
|
|
|
int i;
|
|
|
|
int res;
|
|
|
|
|
|
|
|
for (i = 1; i < NSIG; i++)
|
|
|
|
{
|
|
|
|
res = sigaction (i, &original_signal_actions[i], NULL);
|
|
|
|
if (res == -1 && errno == EINVAL)
|
|
|
|
{
|
|
|
|
/* Some signal numbers in the range are invalid. */
|
|
|
|
continue;
|
|
|
|
}
|
|
|
|
else if (res == -1)
|
2016-08-10 17:06:57 +02:00
|
|
|
perror_with_name (("sigaction"));
|
2016-08-09 21:16:20 +02:00
|
|
|
}
|
|
|
|
|
Add RAII class for blocking gdb signals
This adds configury support and an RAII class that can be used to
temporarily block signals that are used by gdb. (This class is not
used in this patch, but it split out for easier review.)
The idea of this patch is that these signals should only be delivered
to the main thread. So, when creating a background thread, they are
temporarily blocked; the blocked state is inherited by the new thread.
The sigprocmask man page says:
The use of sigprocmask() is unspecified in a multithreaded
process; see pthread_sigmask(3).
This patch changes gdb to use pthread_sigmask when appropriate, by
introducing a convenience define.
I've updated gdbserver as well, because I had to touch gdbsupport, and
because the threading patches will make it link against the thread
library.
I chose not to touch the NTO code, because I don't know anything about
that platform and because I cannot test it.
Finally, this modifies an existing spot in the Guile layer to use the
new facility.
gdb/ChangeLog
2019-11-26 Tom Tromey <tom@tromey.com>
* gdbsupport/signals-state-save-restore.c (original_signal_mask):
Remove comment.
(save_original_signals_state, restore_original_signals_state): Use
gdb_sigmask.
* linux-nat.c (block_child_signals, restore_child_signals_mask)
(_initialize_linux_nat): Use gdb_sigmask.
* guile/guile.c (_initialize_guile): Use block_signals.
* Makefile.in (HFILES_NO_SRCDIR): Add gdb-sigmask.h.
* gdbsupport/gdb-sigmask.h: New file.
* event-top.c (async_sigtstp_handler): Use gdb_sigmask.
* cp-support.c (gdb_demangle): Use gdb_sigmask.
* gdbsupport/common.m4 (GDB_AC_COMMON): Check for
pthread_sigmask.
* configure, config.in: Rebuild.
* gdbsupport/block-signals.h: New file.
gdb/gdbserver/ChangeLog
2019-11-26 Tom Tromey <tom@tromey.com>
* remote-utils.c (block_unblock_async_io): Use gdb_sigmask.
* linux-low.c (linux_wait_for_event_filtered, linux_async): Use
gdb_sigmask.
* configure, config.in: Rebuild.
Change-Id: If3f37dc57dd859c226e9e4d79458a0514746e8c6
2019-09-29 16:50:15 +02:00
|
|
|
res = gdb_sigmask (SIG_SETMASK, &original_signal_mask, NULL);
|
2016-08-09 21:16:20 +02:00
|
|
|
if (res == -1)
|
2016-08-10 17:06:57 +02:00
|
|
|
perror_with_name (("sigprocmask"));
|
2016-08-09 21:16:20 +02:00
|
|
|
#endif
|
|
|
|
}
|