On Mon, 14 Apr 2025, Jakub Jelinek wrote:
> Hi!
>
> Andi had a useful comment that even with the PR119727 workaround to
> ignore differences in libbacktrace printed addresses, it is still better
> to turn off ASLR when easily possible, e.g. in case some address leaks
> in somewhere in the ICE message elsewhere, or to verify the ICE doesn't
> depend on a particular library/binary load addresses.
>
> The following patch adds a configure check and uses personality syscall
> to turn off randomization for further -freport-bug subprocesses.
>
> Bootstrapped/regtested on x86_64-linux and i686-linux, plus verified
> -freport-bug in --enable-host-pie built gcc now prepares bitwise identical
> /tmp/cc*.out dump (previously the libbacktrace addresses in it differed
> between subsequent gcc ... -freport-bug invocations).
> Ok for trunk?
LGTM.
Richard.
> 2025-04-14 Jakub Jelinek <ja...@redhat.com>
>
> PR driver/119727
> * configure.ac (HOST_HAS_PERSONALITY_ADDR_NO_RANDOMIZE): New check.
> * gcc.cc: Include sys/personality.h if
> HOST_HAS_PERSONALITY_ADDR_NO_RANDOMIZE is defined.
> (try_generate_repro): Call
> personality (personality (0xffffffffU) | ADDR_NO_RANDOMIZE)
> if HOST_HAS_PERSONALITY_ADDR_NO_RANDOMIZE is defined.
> * config.in: Regenerate.
> * configure: Regenerate.
>
> --- gcc/configure.ac.jj 2025-04-08 14:08:50.033298821 +0200
> +++ gcc/configure.ac 2025-04-12 17:00:45.773692708 +0200
> @@ -1781,6 +1781,21 @@ if test $ac_cv_have_decl_O_NONBLOCK = ye
> [Define if O_NONBLOCK supported by fcntl.])
> fi
>
> +# Check if personality and ADDR_NO_RANDOMIZE are declared
> +# in sys/personality.h
> +AC_CACHE_CHECK(for personality ADDR_NO_RANDOMIZE,
> + ac_cv_personality_addr_no_randomize, [
> +AC_COMPILE_IFELSE([AC_LANG_PROGRAM([[
> +#include <sys/personality.h>]], [[
> +personality (personality (0xffffffffU) | ADDR_NO_RANDOMIZE);]])],
> +[ac_cv_personality_addr_no_randomize=yes],
> +[ac_cv_personality_addr_no_randomize=no])])
> +if test $ac_cv_personality_addr_no_randomize = yes; then
> + AC_DEFINE(HOST_HAS_PERSONALITY_ADDR_NO_RANDOMIZE, 1,
> + [Define if personality and ADDR_NO_RANDOMIZE are declared in
> +sys/personality.h.])
> +fi
> +
>
> # C++ Modules would like some networking features to provide the mapping
> # server. You can still use modules without them though.
> --- gcc/gcc.cc.jj 2025-04-12 13:15:10.468668500 +0200
> +++ gcc/gcc.cc 2025-04-12 17:08:49.165065782 +0200
> @@ -30,6 +30,9 @@ compilation is specified by a string cal
> #define INCLUDE_STRING
> #include "config.h"
> #include "system.h"
> +#ifdef HOST_HAS_PERSONALITY_ADDR_NO_RANDOMIZE
> +#include <sys/personality.h>
> +#endif
> #include "coretypes.h"
> #include "multilib.h" /* before tm.h */
> #include "tm.h"
> @@ -8003,6 +8006,10 @@ try_generate_repro (const char **argv)
> else
> new_argv[out_arg] = "-o-";
>
> +#ifdef HOST_HAS_PERSONALITY_ADDR_NO_RANDOMIZE
> + personality (personality (0xffffffffU) | ADDR_NO_RANDOMIZE);
> +#endif
> +
> int status;
> for (attempt = 0; attempt < RETRY_ICE_ATTEMPTS; ++attempt)
> {
> --- gcc/config.in.jj 2025-04-08 14:08:48.883314831 +0200
> +++ gcc/config.in 2025-04-12 17:01:17.071263552 +0200
> @@ -2320,6 +2320,13 @@
> #endif
>
>
> +/* Define if personality and ADDR_NO_RANDOMIZE are declared in
> + sys/personality.h. */
> +#ifndef USED_FOR_TARGET
> +#undef HOST_HAS_PERSONALITY_ADDR_NO_RANDOMIZE
> +#endif
> +
> +
> /* Define which stat syscall is able to handle 64bit indodes. */
> #ifndef USED_FOR_TARGET
> #undef HOST_STAT_FOR_64BIT_INODES
> --- gcc/configure.jj 2025-04-08 14:08:50.031298849 +0200
> +++ gcc/configure 2025-04-12 17:01:13.034318999 +0200
> @@ -12694,6 +12694,42 @@ $as_echo "#define HOST_HAS_O_NONBLOCK 1"
>
> fi
>
> +# Check if personality and ADDR_NO_RANDOMIZE are declared
> +# in sys/personality.h
> +{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for personality
> ADDR_NO_RANDOMIZE" >&5
> +$as_echo_n "checking for personality ADDR_NO_RANDOMIZE... " >&6; }
> +if ${ac_cv_personality_addr_no_randomize+:} false; then :
> + $as_echo_n "(cached) " >&6
> +else
> +
> +cat confdefs.h - <<_ACEOF >conftest.$ac_ext
> +/* end confdefs.h. */
> +
> +#include <sys/personality.h>
> +int
> +main ()
> +{
> +
> +personality (personality (0xffffffffU) | ADDR_NO_RANDOMIZE);
> + ;
> + return 0;
> +}
> +_ACEOF
> +if ac_fn_cxx_try_compile "$LINENO"; then :
> + ac_cv_personality_addr_no_randomize=yes
> +else
> + ac_cv_personality_addr_no_randomize=no
> +fi
> +rm -f core conftest.err conftest.$ac_objext conftest.$ac_ext
> +fi
> +{ $as_echo "$as_me:${as_lineno-$LINENO}: result:
> $ac_cv_personality_addr_no_randomize" >&5
> +$as_echo "$ac_cv_personality_addr_no_randomize" >&6; }
> +if test $ac_cv_personality_addr_no_randomize = yes; then
> +
> +$as_echo "#define HOST_HAS_PERSONALITY_ADDR_NO_RANDOMIZE 1" >>confdefs.h
> +
> +fi
> +
>
> # C++ Modules would like some networking features to provide the mapping
> # server. You can still use modules without them though.
> @@ -21484,7 +21520,7 @@ else
> lt_dlunknown=0; lt_dlno_uscore=1; lt_dlneed_uscore=2
> lt_status=$lt_dlunknown
> cat > conftest.$ac_ext <<_LT_EOF
> -#line 21487 "configure"
> +#line 21523 "configure"
> #include "confdefs.h"
>
> #if HAVE_DLFCN_H
> @@ -21590,7 +21626,7 @@ else
> lt_dlunknown=0; lt_dlno_uscore=1; lt_dlneed_uscore=2
> lt_status=$lt_dlunknown
> cat > conftest.$ac_ext <<_LT_EOF
> -#line 21593 "configure"
> +#line 21629 "configure"
> #include "confdefs.h"
>
> #if HAVE_DLFCN_H
>
> Jakub
>
>
--
Richard Biener <rguent...@suse.de>
SUSE Software Solutions Germany GmbH,
Frankenstrasse 146, 90461 Nuernberg, Germany;
GF: Ivo Totev, Andrew McDonald, Werner Knoblich; (HRB 36809, AG Nuernberg)
