| Message ID | 9021f2f9e51e4c7a253d1993ea05f87d0718752f.1359627279.git.mprivozn@redhat.com |
|---|---|
| State | New |
| Headers | show |
Am 31.01.2013 11:15, schrieb Michal Privoznik: > Currently, we are enforcing the _FORTIFY_SOURCE=2 without any > previous detection if the macro has been already defined, e.g. > by environment, or is just enabled by compiler by default. > > Signed-off-by: Michal Privoznik <mprivozn@redhat.com> > --- > configure | 2 +- > 1 file changed, 1 insertion(+), 1 deletion(-) > > diff --git a/configure b/configure > index b7635e4..97070eb 100755 > --- a/configure > +++ b/configure > @@ -3159,7 +3159,7 @@ if test "$gcov" = "yes" ; then > CFLAGS="-fprofile-arcs -ftest-coverage -g $CFLAGS" > LDFLAGS="-fprofile-arcs -ftest-coverage $LDFLAGS" > elif test "$debug" = "no" ; then > - CFLAGS="-O2 -D_FORTIFY_SOURCE=2 $CFLAGS" > + CFLAGS="-O2 -U_FORTIFY_SOURCE -D_FORTIFY_SOURCE=2 $CFLAGS" > fi > > Should we maybe instead add a compile-test? #ifdef _FORTIFY_SOURCE #if _FORTIFY_SOURCE >= 2 #error Environment already has _FORTIFY_SOURCE #endif #endif I admit I have no clue what the number means and whether there are more fortified levels. Cheers, Andreas
On 01.02.2013 10:54, Andreas Färber wrote: > Am 31.01.2013 11:15, schrieb Michal Privoznik: >> Currently, we are enforcing the _FORTIFY_SOURCE=2 without any >> previous detection if the macro has been already defined, e.g. >> by environment, or is just enabled by compiler by default. >> >> Signed-off-by: Michal Privoznik <mprivozn@redhat.com> >> --- >> configure | 2 +- >> 1 file changed, 1 insertion(+), 1 deletion(-) >> >> diff --git a/configure b/configure >> index b7635e4..97070eb 100755 >> --- a/configure >> +++ b/configure >> @@ -3159,7 +3159,7 @@ if test "$gcov" = "yes" ; then >> CFLAGS="-fprofile-arcs -ftest-coverage -g $CFLAGS" >> LDFLAGS="-fprofile-arcs -ftest-coverage $LDFLAGS" >> elif test "$debug" = "no" ; then >> - CFLAGS="-O2 -D_FORTIFY_SOURCE=2 $CFLAGS" >> + CFLAGS="-O2 -U_FORTIFY_SOURCE -D_FORTIFY_SOURCE=2 $CFLAGS" >> fi >> >> > > Should we maybe instead add a compile-test? > > #ifdef _FORTIFY_SOURCE > #if _FORTIFY_SOURCE >= 2 > #error Environment already has _FORTIFY_SOURCE > #endif > #endif > > I admit I have no clue what the number means and whether there are more > fortified levels. > > Cheers, > Andreas > I don't think that's necessary. The 2nd level is the highest one [1] or [2]. It seems like in my case it's compiler who's defining the macro: $ echo "int main() {return 0;}" | gcc -D_FORTIFY_SOURCE=2 -x c - <command-line>:0:0: warning: "_FORTIFY_SOURCE" redefined [enabled by default] <stdin>:1:0: note: this is the location of the previous definition in which case we must undefine it. However, if the _FORTIFY_SOURCE is defined by environment, I think we should not override it. So maybe need a different approach. Anyway, with current state I cannot compile. I am using gcc version 4.7.2 (Gentoo 4.7.2 p1.3, pie-0.5.5) Michal 1: http://gcc.gnu.org/ml/gcc-patches/2004-09/msg02055.html 2: http://gcc.gnu.org/git/?p=gcc.git;a=blob;f=libssp/ssp/ssp.h.in
On Fri, Feb 01, 2013 at 04:18:23PM +0100, Michal Privoznik wrote: > On 01.02.2013 10:54, Andreas Färber wrote: > > Am 31.01.2013 11:15, schrieb Michal Privoznik: > >> Currently, we are enforcing the _FORTIFY_SOURCE=2 without any > >> previous detection if the macro has been already defined, e.g. > >> by environment, or is just enabled by compiler by default. > >> > >> Signed-off-by: Michal Privoznik <mprivozn@redhat.com> > >> --- > >> configure | 2 +- > >> 1 file changed, 1 insertion(+), 1 deletion(-) > >> > >> diff --git a/configure b/configure > >> index b7635e4..97070eb 100755 > >> --- a/configure > >> +++ b/configure > >> @@ -3159,7 +3159,7 @@ if test "$gcov" = "yes" ; then > >> CFLAGS="-fprofile-arcs -ftest-coverage -g $CFLAGS" > >> LDFLAGS="-fprofile-arcs -ftest-coverage $LDFLAGS" > >> elif test "$debug" = "no" ; then > >> - CFLAGS="-O2 -D_FORTIFY_SOURCE=2 $CFLAGS" > >> + CFLAGS="-O2 -U_FORTIFY_SOURCE -D_FORTIFY_SOURCE=2 $CFLAGS" > >> fi > >> > >> > > > > Should we maybe instead add a compile-test? > > > > #ifdef _FORTIFY_SOURCE > > #if _FORTIFY_SOURCE >= 2 > > #error Environment already has _FORTIFY_SOURCE > > #endif > > #endif > > > > I admit I have no clue what the number means and whether there are more > > fortified levels. > > > > Cheers, > > Andreas > > > > I don't think that's necessary. The 2nd level is the highest one [1] or [2]. > It seems like in my case it's compiler who's defining the macro: > > $ echo "int main() {return 0;}" | gcc -D_FORTIFY_SOURCE=2 -x c - > <command-line>:0:0: warning: "_FORTIFY_SOURCE" redefined [enabled by default] > <stdin>:1:0: note: this is the location of the previous definition > > in which case we must undefine it. However, if the _FORTIFY_SOURCE is > defined by environment, I think we should not override it. So maybe need > a different approach. Anyway, with current state I cannot compile. I am using > gcc version 4.7.2 (Gentoo 4.7.2 p1.3, pie-0.5.5) It would be nice to fix this for QEMU 1.4 but my gcc FORTIFY_SOURCE foo is not strong enough to know what the best approach is here. Reviews from anyone else? Stefan
Il 06/02/2013 15:49, Stefan Hajnoczi ha scritto: >> > I don't think that's necessary. The 2nd level is the highest one [1] or [2]. >> > It seems like in my case it's compiler who's defining the macro: >> > >> > $ echo "int main() {return 0;}" | gcc -D_FORTIFY_SOURCE=2 -x c - >> > <command-line>:0:0: warning: "_FORTIFY_SOURCE" redefined [enabled by default] >> > <stdin>:1:0: note: this is the location of the previous definition >> > >> > in which case we must undefine it. However, if the _FORTIFY_SOURCE is >> > defined by environment, I think we should not override it. So maybe need >> > a different approach. Anyway, with current state I cannot compile. I am using >> > gcc version 4.7.2 (Gentoo 4.7.2 p1.3, pie-0.5.5) > It would be nice to fix this for QEMU 1.4 but my gcc FORTIFY_SOURCE foo > is not strong enough to know what the best approach is here. > > Reviews from anyone else? I would prefer to avoid having _FORTIFY_SOURCE completely, and let distros do it. Alternatively, tie it to a new --enable switch which would do -U -D. But if there is a real problem for 1.4 the patch looks good. Paolo
On 2013-02-06 06:49, Stefan Hajnoczi wrote: >> $ echo "int main() {return 0;}" | gcc -D_FORTIFY_SOURCE=2 -x c - >> <command-line>:0:0: warning: "_FORTIFY_SOURCE" redefined [enabled by default] >> <stdin>:1:0: note: this is the location of the previous definition >> >> in which case we must undefine it. However, if the _FORTIFY_SOURCE is >> defined by environment, I think we should not override it. So maybe need >> a different approach. Anyway, with current state I cannot compile. I am using >> gcc version 4.7.2 (Gentoo 4.7.2 p1.3, pie-0.5.5) > > It would be nice to fix this for QEMU 1.4 but my gcc FORTIFY_SOURCE foo > is not strong enough to know what the best approach is here. Using -U -D is just fine to override something that the distro turned on by default. r~
On 06.02.2013 16:09, Paolo Bonzini wrote: > Il 06/02/2013 15:49, Stefan Hajnoczi ha scritto: >>>> I don't think that's necessary. The 2nd level is the highest one [1] or [2]. >>>> It seems like in my case it's compiler who's defining the macro: >>>> >>>> $ echo "int main() {return 0;}" | gcc -D_FORTIFY_SOURCE=2 -x c - >>>> <command-line>:0:0: warning: "_FORTIFY_SOURCE" redefined [enabled by default] >>>> <stdin>:1:0: note: this is the location of the previous definition >>>> >>>> in which case we must undefine it. However, if the _FORTIFY_SOURCE is >>>> defined by environment, I think we should not override it. So maybe need >>>> a different approach. Anyway, with current state I cannot compile. I am using >>>> gcc version 4.7.2 (Gentoo 4.7.2 p1.3, pie-0.5.5) >> It would be nice to fix this for QEMU 1.4 but my gcc FORTIFY_SOURCE foo >> is not strong enough to know what the best approach is here. >> >> Reviews from anyone else? > > I would prefer to avoid having _FORTIFY_SOURCE completely, and let > distros do it. Alternatively, tie it to a new --enable switch which > would do -U -D. > > But if there is a real problem for 1.4 the patch looks good. > > Paolo > Sorry for resurrecting such old thread, but what's the conclusion then? I keep hitting this problem and I am tired of having one single patch on the top of HEAD. And I bet others ran into this as well. Michal
Michal Privoznik <mprivozn@redhat.com> writes: > On 06.02.2013 16:09, Paolo Bonzini wrote: >> Il 06/02/2013 15:49, Stefan Hajnoczi ha scritto: >>>>> I don't think that's necessary. The 2nd level is the highest one >>>>> [1] or [2]. >>>>> It seems like in my case it's compiler who's defining the macro: >>>>> >>>>> $ echo "int main() {return 0;}" | gcc -D_FORTIFY_SOURCE=2 -x c - >>>>> <command-line>:0:0: warning: "_FORTIFY_SOURCE" redefined [enabled >>>>> by default] >>>>> <stdin>:1:0: note: this is the location of the previous definition >>>>> >>>>> in which case we must undefine it. However, if the _FORTIFY_SOURCE is >>>>> defined by environment, I think we should not override it. So maybe need >>>>> a different approach. Anyway, with current state I cannot >>>>> compile. I am using >>>>> gcc version 4.7.2 (Gentoo 4.7.2 p1.3, pie-0.5.5) >>> It would be nice to fix this for QEMU 1.4 but my gcc FORTIFY_SOURCE foo >>> is not strong enough to know what the best approach is here. >>> >>> Reviews from anyone else? >> >> I would prefer to avoid having _FORTIFY_SOURCE completely, and let >> distros do it. Alternatively, tie it to a new --enable switch which >> would do -U -D. >> >> But if there is a real problem for 1.4 the patch looks good. >> >> Paolo >> > > Sorry for resurrecting such old thread, but what's the conclusion then? Thread petered out without a conclusion? > I keep hitting this problem and I am tired of having one single patch on > the top of HEAD. And I bet others ran into this as well. Few things focus discussions as well as a patch does. Suggest to post one to get things going again.
diff --git a/configure b/configure index b7635e4..97070eb 100755 --- a/configure +++ b/configure @@ -3159,7 +3159,7 @@ if test "$gcov" = "yes" ; then CFLAGS="-fprofile-arcs -ftest-coverage -g $CFLAGS" LDFLAGS="-fprofile-arcs -ftest-coverage $LDFLAGS" elif test "$debug" = "no" ; then - CFLAGS="-O2 -D_FORTIFY_SOURCE=2 $CFLAGS" + CFLAGS="-O2 -U_FORTIFY_SOURCE -D_FORTIFY_SOURCE=2 $CFLAGS" fi
Currently, we are enforcing the _FORTIFY_SOURCE=2 without any previous detection if the macro has been already defined, e.g. by environment, or is just enabled by compiler by default. Signed-off-by: Michal Privoznik <mprivozn@redhat.com> --- configure | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-)