* [PATCH v3 0/3] Properly handle DT_RUNPATH
@ 2021-12-08 15:24 H.J. Lu
2021-12-08 15:24 ` [PATCH v3 1/3] Add and use link-test-modules-rpath-link [BZ #28455] H.J. Lu
` (2 more replies)
0 siblings, 3 replies; 8+ messages in thread
From: H.J. Lu @ 2021-12-08 15:24 UTC (permalink / raw)
To: libc-alpha
DT_RUNPATH is only used to find the immediate dependencies of the
executable or shared object containing the DT_RUNPATH entry:
1. Define link-test-modules-rpath-link if $(build-hardcoded-path-in-tests)
is yes.
2. Use $(link-test-modules-rpath-link) in build-module-helper so that
test modules can dlopen modules with DT_RUNPATH.
3. Add a test to show why link-test-modules-rpath-link is needed.
4. The glibc internal NSS functions should always load NSS modules from
the system. For testing purpose, disable DT_RUNPATH on NSS tests so
that the glibc internal NSS functions can load testing NSS modules
via DT_RPATH.
5. Update glibc LD_AUDIT dlopen call to try the DT_RUNPATH entry of the
executable.
H.J. Lu (3):
Add and use link-test-modules-rpath-link [BZ #28455]
Disable DT_RUNPATH on NSS tests [BZ #28455]
elf: Also try DT_RUNPATH for LD_AUDIT dlopen [BZ #28455]
Makeconfig | 2 ++
Makerules | 1 +
elf/Makefile | 16 ++++++++++++++--
elf/dl-load.c | 15 +++++++++++++++
elf/tst-audit14a.c | 1 +
elf/tst-global2.c | 32 ++++++++++++++++++++++++++++++++
elf/tst-globalmod2.c | 41 +++++++++++++++++++++++++++++++++++++++++
nss/Makefile | 8 ++++++++
8 files changed, 114 insertions(+), 2 deletions(-)
create mode 100644 elf/tst-audit14a.c
create mode 100644 elf/tst-global2.c
create mode 100644 elf/tst-globalmod2.c
--
2.33.1
^ permalink raw reply [flat|nested] 8+ messages in thread* [PATCH v3 1/3] Add and use link-test-modules-rpath-link [BZ #28455] 2021-12-08 15:24 [PATCH v3 0/3] Properly handle DT_RUNPATH H.J. Lu @ 2021-12-08 15:24 ` H.J. Lu 2021-12-13 15:32 ` Carlos O'Donell 2021-12-08 15:25 ` [PATCH v3 2/3] Disable DT_RUNPATH on NSS tests " H.J. Lu 2021-12-08 15:25 ` [PATCH v3 3/3] elf: Also try DT_RUNPATH for LD_AUDIT dlopen " H.J. Lu 2 siblings, 1 reply; 8+ messages in thread From: H.J. Lu @ 2021-12-08 15:24 UTC (permalink / raw) To: libc-alpha DT_RUNPATH is only used to find the immediate dependencies of the executable or shared object containing the DT_RUNPATH entry: 1. Define link-test-modules-rpath-link if $(build-hardcoded-path-in-tests) is yes. 2. Use $(link-test-modules-rpath-link) in build-module-helper so that test modules can dlopen modules with DT_RUNPATH. 3. Add a test to show why link-test-modules-rpath-link is needed. This partially fixes BZ #28455. --- Makeconfig | 2 ++ Makerules | 1 + elf/Makefile | 7 +++++++ elf/tst-global2.c | 32 ++++++++++++++++++++++++++++++++ elf/tst-globalmod2.c | 41 +++++++++++++++++++++++++++++++++++++++++ 5 files changed, 83 insertions(+) create mode 100644 elf/tst-global2.c create mode 100644 elf/tst-globalmod2.c diff --git a/Makeconfig b/Makeconfig index 3fa2f13003..2e2b6dbdf9 100644 --- a/Makeconfig +++ b/Makeconfig @@ -569,8 +569,10 @@ link-libc-rpath-link = -Wl,-rpath-link=$(rpath-link) # build-hardcoded-path-in-tests. ifeq (yes,$(build-hardcoded-path-in-tests)) link-libc-tests-rpath-link = $(link-libc-rpath) +link-test-modules-rpath-link = $(link-libc-rpath) else link-libc-tests-rpath-link = $(link-libc-rpath-link) +link-test-modules-rpath-link = endif # build-hardcoded-path-in-tests link-libc-between-gnulib = $(common-objpfx)libc.so$(libc.so-version) \ diff --git a/Makerules b/Makerules index 8db0ca1296..7afba30039 100644 --- a/Makerules +++ b/Makerules @@ -591,6 +591,7 @@ $(LINK.o) -shared -static-libgcc $(sysdep-LDFLAGS) $(rtld-LDFLAGS) \ $(if $($(@F)-no-z-defs)$(no-z-defs),,-Wl,-z,defs) \ -B$(csu-objpfx) $(load-map-file) \ $(LDFLAGS.so) $(LDFLAGS-$(@F:%.so=%).so) \ + $(link-test-modules-rpath-link) \ -L$(subst :, -L,$(rpath-link)) -Wl,-rpath-link=$(rpath-link) endef diff --git a/elf/Makefile b/elf/Makefile index ef36008673..4b5bdcb08e 100644 --- a/elf/Makefile +++ b/elf/Makefile @@ -232,6 +232,7 @@ tests += restest1 preloadtest loadfail multiload origtest resolvfail \ tst-dl-is_dso tst-ro-dynamic \ tst-audit18 \ tst-rtld-run-static \ + tst-global2 \ # reldep9 tests-internal += loadtest unload unload2 circleload1 \ neededtest neededtest2 neededtest3 neededtest4 \ @@ -374,6 +375,7 @@ modules-names = testobj1 testobj2 testobj3 testobj4 testobj5 testobj6 \ tst-dlmopen-gethostbyname-mod tst-ro-dynamic-mod \ tst-auditmod18 \ tst-audit18mod \ + tst-globalmod2 \ # Most modules build with _ISOMAC defined, but those filtered out # depend on internal headers. @@ -1310,6 +1312,11 @@ tst-audit8-ENV = LD_AUDIT=$(objpfx)tst-auditmod1.so $(objpfx)tst-global1.out: $(objpfx)testobj6.so $(objpfx)testobj2.so +$(objpfx)tst-global2: $(objpfx)tst-globalmod2.so +$(objpfx)tst-global2.out: $(objpfx)reldepmod1.so $(objpfx)reldepmod4.so +LDFLAGS-tst-global2 = -Wl,--enable-new-dtags +LDFLAGS-tst-globalmod2.so = -Wl,--enable-new-dtags + $(objpfx)order2.out: $(objpfx)order2mod1.so $(objpfx)order2mod2.so $(objpfx)order2-cmp.out: $(objpfx)order2.out (echo "12345" | cmp $< -) > $@; \ diff --git a/elf/tst-global2.c b/elf/tst-global2.c new file mode 100644 index 0000000000..e929f526f4 --- /dev/null +++ b/elf/tst-global2.c @@ -0,0 +1,32 @@ +/* Test BZ #28455. + Copyright (C) 2021 Free Software Foundation, Inc. + This file is part of the GNU C Library. + + The GNU C Library is free software; you can redistribute it and/or + modify it under the terms of the GNU Lesser General Public + License as published by the Free Software Foundation; either + version 2.1 of the License, or (at your option) any later version. + + The GNU C Library is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public + License along with the GNU C Library; if not, see + <https://www.gnu.org/licenses/>. */ + +/* In glibc configured with --enable-hardcoded-path-in-tests, a test + program built with -Wl,--enable-new-dtags, which adds DT_RUNPATH, + instead of DT_RPATH, can call a function in a shared library, which + dlopens another shared library. */ + +extern int test (void); + +static int +do_test (void) +{ + return test (); +} + +#include <support/test-driver.c> diff --git a/elf/tst-globalmod2.c b/elf/tst-globalmod2.c new file mode 100644 index 0000000000..6fd70a72a8 --- /dev/null +++ b/elf/tst-globalmod2.c @@ -0,0 +1,41 @@ +/* Test BZ #28455. + Copyright (C) 2021 Free Software Foundation, Inc. + This file is part of the GNU C Library. + + The GNU C Library is free software; you can redistribute it and/or + modify it under the terms of the GNU Lesser General Public + License as published by the Free Software Foundation; either + version 2.1 of the License, or (at your option) any later version. + + The GNU C Library is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + Lesser General Public License for more details. + + You should have received a copy of the GNU Lesser General Public + License along with the GNU C Library; if not, see + <https://www.gnu.org/licenses/>. */ + +/* In glibc configured with --enable-hardcoded-path-in-tests, a test + program built with -Wl,--enable-new-dtags, which adds DT_RUNPATH, + instead of DT_RPATH, can call a function in a shared library, which + dlopens another shared library. */ + +#include <dlfcn.h> +#include <stdio.h> +#include <stdlib.h> + +extern int test (void); + +int +test (void) +{ + (void) dlopen ("reldepmod4.so", RTLD_LAZY | RTLD_GLOBAL); + if (dlsym (RTLD_DEFAULT, "call_me") != NULL) + { + puts ("found \"call_me\""); + return EXIT_SUCCESS; + } + puts ("didn't find \"call_me\""); + return EXIT_FAILURE; +} -- 2.33.1 ^ permalink raw reply [flat|nested] 8+ messages in thread
* Re: [PATCH v3 1/3] Add and use link-test-modules-rpath-link [BZ #28455] 2021-12-08 15:24 ` [PATCH v3 1/3] Add and use link-test-modules-rpath-link [BZ #28455] H.J. Lu @ 2021-12-13 15:32 ` Carlos O'Donell 0 siblings, 0 replies; 8+ messages in thread From: Carlos O'Donell @ 2021-12-13 15:32 UTC (permalink / raw) To: H.J. Lu, libc-alpha On 12/8/21 10:24, H.J. Lu wrote: > DT_RUNPATH is only used to find the immediate dependencies of the > executable or shared object containing the DT_RUNPATH entry: > > 1. Define link-test-modules-rpath-link if $(build-hardcoded-path-in-tests) > is yes. > 2. Use $(link-test-modules-rpath-link) in build-module-helper so that > test modules can dlopen modules with DT_RUNPATH. > 3. Add a test to show why link-test-modules-rpath-link is needed. I think should go in regardless of my suggestions in 3/3. Please post a v4 that is distinct from your series and I'll ACK that. > This partially fixes BZ #28455. > --- > Makeconfig | 2 ++ > Makerules | 1 + > elf/Makefile | 7 +++++++ > elf/tst-global2.c | 32 ++++++++++++++++++++++++++++++++ > elf/tst-globalmod2.c | 41 +++++++++++++++++++++++++++++++++++++++++ > 5 files changed, 83 insertions(+) > create mode 100644 elf/tst-global2.c > create mode 100644 elf/tst-globalmod2.c > > diff --git a/Makeconfig b/Makeconfig > index 3fa2f13003..2e2b6dbdf9 100644 > --- a/Makeconfig > +++ b/Makeconfig > @@ -569,8 +569,10 @@ link-libc-rpath-link = -Wl,-rpath-link=$(rpath-link) > # build-hardcoded-path-in-tests. > ifeq (yes,$(build-hardcoded-path-in-tests)) > link-libc-tests-rpath-link = $(link-libc-rpath) > +link-test-modules-rpath-link = $(link-libc-rpath) OK. Use $(link-libc-rpath) if we are using $(build-hardcoded-path-in-tests) because with DT_RUNPATH we may need to find the paths with DT_RUNPATH. > else > link-libc-tests-rpath-link = $(link-libc-rpath-link) > +link-test-modules-rpath-link = OK. Otherwise nothing. > endif # build-hardcoded-path-in-tests > > link-libc-between-gnulib = $(common-objpfx)libc.so$(libc.so-version) \ > diff --git a/Makerules b/Makerules > index 8db0ca1296..7afba30039 100644 > --- a/Makerules > +++ b/Makerules > @@ -591,6 +591,7 @@ $(LINK.o) -shared -static-libgcc $(sysdep-LDFLAGS) $(rtld-LDFLAGS) \ > $(if $($(@F)-no-z-defs)$(no-z-defs),,-Wl,-z,defs) \ > -B$(csu-objpfx) $(load-map-file) \ > $(LDFLAGS.so) $(LDFLAGS-$(@F:%.so=%).so) \ > + $(link-test-modules-rpath-link) \ OK. > -L$(subst :, -L,$(rpath-link)) -Wl,-rpath-link=$(rpath-link) > endef > > diff --git a/elf/Makefile b/elf/Makefile > index ef36008673..4b5bdcb08e 100644 > --- a/elf/Makefile > +++ b/elf/Makefile > @@ -232,6 +232,7 @@ tests += restest1 preloadtest loadfail multiload origtest resolvfail \ > tst-dl-is_dso tst-ro-dynamic \ > tst-audit18 \ > tst-rtld-run-static \ > + tst-global2 \ Please split and sort to reduce conflicts. > # reldep9 > tests-internal += loadtest unload unload2 circleload1 \ > neededtest neededtest2 neededtest3 neededtest4 \ > @@ -374,6 +375,7 @@ modules-names = testobj1 testobj2 testobj3 testobj4 testobj5 testobj6 \ > tst-dlmopen-gethostbyname-mod tst-ro-dynamic-mod \ > tst-auditmod18 \ > tst-audit18mod \ > + tst-globalmod2 \ Likewise. > > # Most modules build with _ISOMAC defined, but those filtered out > # depend on internal headers. > @@ -1310,6 +1312,11 @@ tst-audit8-ENV = LD_AUDIT=$(objpfx)tst-auditmod1.so > > $(objpfx)tst-global1.out: $(objpfx)testobj6.so $(objpfx)testobj2.so > > +$(objpfx)tst-global2: $(objpfx)tst-globalmod2.so OK. Dep is present for build. > +$(objpfx)tst-global2.out: $(objpfx)reldepmod1.so $(objpfx)reldepmod4.so OK. Dep on reldepmod4.so is present for correct buildordering. > +LDFLAGS-tst-global2 = -Wl,--enable-new-dtags > +LDFLAGS-tst-globalmod2.so = -Wl,--enable-new-dtags OK. Force DT_RUNPATH. > + > $(objpfx)order2.out: $(objpfx)order2mod1.so $(objpfx)order2mod2.so > $(objpfx)order2-cmp.out: $(objpfx)order2.out > (echo "12345" | cmp $< -) > $@; \ > diff --git a/elf/tst-global2.c b/elf/tst-global2.c > new file mode 100644 > index 0000000000..e929f526f4 > --- /dev/null > +++ b/elf/tst-global2.c > @@ -0,0 +1,32 @@ > +/* Test BZ #28455. OK. > + Copyright (C) 2021 Free Software Foundation, Inc. > + This file is part of the GNU C Library. > + > + The GNU C Library is free software; you can redistribute it and/or > + modify it under the terms of the GNU Lesser General Public > + License as published by the Free Software Foundation; either > + version 2.1 of the License, or (at your option) any later version. > + > + The GNU C Library is distributed in the hope that it will be useful, > + but WITHOUT ANY WARRANTY; without even the implied warranty of > + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU > + Lesser General Public License for more details. > + > + You should have received a copy of the GNU Lesser General Public > + License along with the GNU C Library; if not, see > + <https://www.gnu.org/licenses/>. */ > + > +/* In glibc configured with --enable-hardcoded-path-in-tests, a test > + program built with -Wl,--enable-new-dtags, which adds DT_RUNPATH, > + instead of DT_RPATH, can call a function in a shared library, which > + dlopens another shared library. */ > + > +extern int test (void); > + > +static int > +do_test (void) > +{ > + return test (); > +} > + > +#include <support/test-driver.c> > diff --git a/elf/tst-globalmod2.c b/elf/tst-globalmod2.c > new file mode 100644 > index 0000000000..6fd70a72a8 > --- /dev/null > +++ b/elf/tst-globalmod2.c > @@ -0,0 +1,41 @@ > +/* Test BZ #28455. > + Copyright (C) 2021 Free Software Foundation, Inc. > + This file is part of the GNU C Library. > + > + The GNU C Library is free software; you can redistribute it and/or > + modify it under the terms of the GNU Lesser General Public > + License as published by the Free Software Foundation; either > + version 2.1 of the License, or (at your option) any later version. > + > + The GNU C Library is distributed in the hope that it will be useful, > + but WITHOUT ANY WARRANTY; without even the implied warranty of > + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU > + Lesser General Public License for more details. > + > + You should have received a copy of the GNU Lesser General Public > + License along with the GNU C Library; if not, see > + <https://www.gnu.org/licenses/>. */ > + > +/* In glibc configured with --enable-hardcoded-path-in-tests, a test > + program built with -Wl,--enable-new-dtags, which adds DT_RUNPATH, > + instead of DT_RPATH, can call a function in a shared library, which > + dlopens another shared library. */ > + > +#include <dlfcn.h> > +#include <stdio.h> > +#include <stdlib.h> > + > +extern int test (void); > + > +int > +test (void) > +{ > + (void) dlopen ("reldepmod4.so", RTLD_LAZY | RTLD_GLOBAL); OK. Will test that we can find the DSOs from build directory. > + if (dlsym (RTLD_DEFAULT, "call_me") != NULL) > + { > + puts ("found \"call_me\""); > + return EXIT_SUCCESS; > + } > + puts ("didn't find \"call_me\""); > + return EXIT_FAILURE; > +} > -- Cheers, Carlos. ^ permalink raw reply [flat|nested] 8+ messages in thread
* [PATCH v3 2/3] Disable DT_RUNPATH on NSS tests [BZ #28455] 2021-12-08 15:24 [PATCH v3 0/3] Properly handle DT_RUNPATH H.J. Lu 2021-12-08 15:24 ` [PATCH v3 1/3] Add and use link-test-modules-rpath-link [BZ #28455] H.J. Lu @ 2021-12-08 15:25 ` H.J. Lu 2021-12-13 15:29 ` Carlos O'Donell 2021-12-08 15:25 ` [PATCH v3 3/3] elf: Also try DT_RUNPATH for LD_AUDIT dlopen " H.J. Lu 2 siblings, 1 reply; 8+ messages in thread From: H.J. Lu @ 2021-12-08 15:25 UTC (permalink / raw) To: libc-alpha The glibc internal NSS functions should always load NSS modules from the system. For testing purpose, disable DT_RUNPATH on NSS tests so that the glibc internal NSS functions can load testing NSS modules via DT_RPATH. This partially fixes BZ #28455. --- nss/Makefile | 8 ++++++++ 1 file changed, 8 insertions(+) diff --git a/nss/Makefile b/nss/Makefile index bccf9f2806..757446f80a 100644 --- a/nss/Makefile +++ b/nss/Makefile @@ -189,3 +189,11 @@ endif $(objpfx)tst-nss-files-alias-leak.out: $(objpfx)/libnss_files.so $(objpfx)tst-nss-files-alias-truncated.out: $(objpfx)/libnss_files.so + +# Disable DT_RUNPATH on NSS tests so that the glibc internal NSS +# functions can load testing NSS modules via DT_RPATH. +LDFLAGS-tst-nss-test1 = -Wl,--disable-new-dtags +LDFLAGS-tst-nss-test2 = -Wl,--disable-new-dtags +LDFLAGS-tst-nss-test3 = -Wl,--disable-new-dtags +LDFLAGS-tst-nss-test4 = -Wl,--disable-new-dtags +LDFLAGS-tst-nss-test5 = -Wl,--disable-new-dtags -- 2.33.1 ^ permalink raw reply [flat|nested] 8+ messages in thread
* Re: [PATCH v3 2/3] Disable DT_RUNPATH on NSS tests [BZ #28455] 2021-12-08 15:25 ` [PATCH v3 2/3] Disable DT_RUNPATH on NSS tests " H.J. Lu @ 2021-12-13 15:29 ` Carlos O'Donell 0 siblings, 0 replies; 8+ messages in thread From: Carlos O'Donell @ 2021-12-13 15:29 UTC (permalink / raw) To: H.J. Lu, libc-alpha On 12/8/21 10:25, H.J. Lu wrote: > The glibc internal NSS functions should always load NSS modules from > the system. For testing purpose, disable DT_RUNPATH on NSS tests so > that the glibc internal NSS functions can load testing NSS modules > via DT_RPATH. I agree that we should have a consistent tests that are not impacted by the specific choices of the system toolchain. Using --disable-new-dtags is sufficient to make this consistent. If we need *more* tests then we can add them. This change should go in regardless of my comments in 3/3. LGTM. Reviewed-by: Carlos O'Donell <carlos@redhat.com> > This partially fixes BZ #28455. > --- > nss/Makefile | 8 ++++++++ > 1 file changed, 8 insertions(+) > > diff --git a/nss/Makefile b/nss/Makefile > index bccf9f2806..757446f80a 100644 > --- a/nss/Makefile > +++ b/nss/Makefile > @@ -189,3 +189,11 @@ endif > > $(objpfx)tst-nss-files-alias-leak.out: $(objpfx)/libnss_files.so > $(objpfx)tst-nss-files-alias-truncated.out: $(objpfx)/libnss_files.so > + > +# Disable DT_RUNPATH on NSS tests so that the glibc internal NSS > +# functions can load testing NSS modules via DT_RPATH. > +LDFLAGS-tst-nss-test1 = -Wl,--disable-new-dtags > +LDFLAGS-tst-nss-test2 = -Wl,--disable-new-dtags > +LDFLAGS-tst-nss-test3 = -Wl,--disable-new-dtags > +LDFLAGS-tst-nss-test4 = -Wl,--disable-new-dtags > +LDFLAGS-tst-nss-test5 = -Wl,--disable-new-dtags OK. I agree that this is one solution, and that it will work. > -- Cheers, Carlos. ^ permalink raw reply [flat|nested] 8+ messages in thread
* [PATCH v3 3/3] elf: Also try DT_RUNPATH for LD_AUDIT dlopen [BZ #28455] 2021-12-08 15:24 [PATCH v3 0/3] Properly handle DT_RUNPATH H.J. Lu 2021-12-08 15:24 ` [PATCH v3 1/3] Add and use link-test-modules-rpath-link [BZ #28455] H.J. Lu 2021-12-08 15:25 ` [PATCH v3 2/3] Disable DT_RUNPATH on NSS tests " H.J. Lu @ 2021-12-08 15:25 ` H.J. Lu 2021-12-13 22:07 ` Carlos O'Donell 2 siblings, 1 reply; 8+ messages in thread From: H.J. Lu @ 2021-12-08 15:25 UTC (permalink / raw) To: libc-alpha DT_RUNPATH is only used to find the immediate dependencies of the executable or shared object containing the DT_RUNPATH entry. Update the glibc LD_AUDIT dlopen call to try the DT_RUNPATH entry of the executable. This partially fixes BZ #28455. --- elf/Makefile | 9 +++++++-- elf/dl-load.c | 15 +++++++++++++++ elf/tst-audit14a.c | 1 + 3 files changed, 23 insertions(+), 2 deletions(-) create mode 100644 elf/tst-audit14a.c diff --git a/elf/Makefile b/elf/Makefile index 4b5bdcb08e..aa6b24d790 100644 --- a/elf/Makefile +++ b/elf/Makefile @@ -247,10 +247,10 @@ ifneq ($(selinux-enabled),1) tests-execstack-yes = tst-execstack tst-execstack-needed tst-execstack-prog endif ifeq ($(have-depaudit),yes) -tests += tst-audit14 tst-audit15 tst-audit16 +tests += tst-audit14 tst-audit15 tst-audit16 tst-audit14a ifeq ($(run-built-tests),yes) tests-special += $(objpfx)tst-audit14-cmp.out $(objpfx)tst-audit15-cmp.out \ - $(objpfx)tst-audit16-cmp.out + $(objpfx)tst-audit16-cmp.out $(objpfx)tst-audit14a-cmp.out endif endif endif @@ -1521,6 +1521,8 @@ tst-auditmany-ENV = \ LDFLAGS-tst-audit14 = -Wl,--audit=tst-auditlogmod-1.so $(objpfx)tst-auditlogmod-1.so: $(libsupport) $(objpfx)tst-audit14.out: $(objpfx)tst-auditlogmod-1.so +LDFLAGS-tst-audit14a = -Wl,--audit=tst-auditlogmod-1.so,--enable-new-dtags +$(objpfx)tst-audit14a.out: $(objpfx)tst-auditlogmod-1.so LDFLAGS-tst-audit15 = \ -Wl,--audit=tst-auditlogmod-1.so,--depaudit=tst-auditlogmod-2.so $(objpfx)tst-auditlogmod-2.so: $(libsupport) @@ -1547,6 +1549,9 @@ tst-audit17-ENV = LD_AUDIT=$(objpfx)tst-auditmod17.so $(objpfx)tst-audit14-cmp.out: tst-audit14.exp $(objpfx)tst-audit14.out cmp $^ > $@; \ $(evaluate-test) +$(objpfx)tst-audit14a-cmp.out: tst-audit14.exp $(objpfx)tst-audit14a.out + cmp $^ > $@; \ + $(evaluate-test) $(objpfx)tst-audit15-cmp.out: tst-audit15.exp $(objpfx)tst-audit15.out cmp $^ > $@; \ $(evaluate-test) diff --git a/elf/dl-load.c b/elf/dl-load.c index bf8957e73c..1f424ea7c8 100644 --- a/elf/dl-load.c +++ b/elf/dl-load.c @@ -2175,6 +2175,21 @@ _dl_map_object (struct link_map *loader, const char *name, &main_map->l_rpath_dirs, &realname, &fb, loader ?: main_map, LA_SER_RUNPATH, &found_other_class); + + /* Also try DT_RUNPATH in the executable for glibc internal + dlopen call. */ + if (__glibc_unlikely (mode & __RTLD_AUDIT) + && fd == -1 && !did_main_map + && main_map != NULL && main_map->l_type != lt_loaded) + { + struct r_search_path_struct l_rpath_dirs; + l_rpath_dirs.dirs = NULL; + if (cache_rpath (main_map, &l_rpath_dirs, + DT_RUNPATH, "RUNPATH")) + fd = open_path (name, namelen, mode, &l_rpath_dirs, + &realname, &fb, loader ?: main_map, + LA_SER_RUNPATH, &found_other_class); + } } /* Try the LD_LIBRARY_PATH environment variable. */ diff --git a/elf/tst-audit14a.c b/elf/tst-audit14a.c new file mode 100644 index 0000000000..c6232eacf2 --- /dev/null +++ b/elf/tst-audit14a.c @@ -0,0 +1 @@ +#include "tst-audit14.c" -- 2.33.1 ^ permalink raw reply [flat|nested] 8+ messages in thread
* Re: [PATCH v3 3/3] elf: Also try DT_RUNPATH for LD_AUDIT dlopen [BZ #28455] 2021-12-08 15:25 ` [PATCH v3 3/3] elf: Also try DT_RUNPATH for LD_AUDIT dlopen " H.J. Lu @ 2021-12-13 22:07 ` Carlos O'Donell 2021-12-16 2:07 ` H.J. Lu 0 siblings, 1 reply; 8+ messages in thread From: Carlos O'Donell @ 2021-12-13 22:07 UTC (permalink / raw) To: H.J. Lu, libc-alpha On 12/8/21 10:25, H.J. Lu wrote: > DT_RUNPATH is only used to find the immediate dependencies of the > executable or shared object containing the DT_RUNPATH entry. Update > the glibc LD_AUDIT dlopen call to try the DT_RUNPATH entry of the > executable. This partially fixes BZ #28455. Please post v4 split out. > --- > elf/Makefile | 9 +++++++-- > elf/dl-load.c | 15 +++++++++++++++ > elf/tst-audit14a.c | 1 + > 3 files changed, 23 insertions(+), 2 deletions(-) > create mode 100644 elf/tst-audit14a.c > > diff --git a/elf/Makefile b/elf/Makefile > index 4b5bdcb08e..aa6b24d790 100644 > --- a/elf/Makefile > +++ b/elf/Makefile > @@ -247,10 +247,10 @@ ifneq ($(selinux-enabled),1) > tests-execstack-yes = tst-execstack tst-execstack-needed tst-execstack-prog > endif > ifeq ($(have-depaudit),yes) > -tests += tst-audit14 tst-audit15 tst-audit16 > +tests += tst-audit14 tst-audit15 tst-audit16 tst-audit14a Please split one test per line and sort. > ifeq ($(run-built-tests),yes) > tests-special += $(objpfx)tst-audit14-cmp.out $(objpfx)tst-audit15-cmp.out \ > - $(objpfx)tst-audit16-cmp.out > + $(objpfx)tst-audit16-cmp.out $(objpfx)tst-audit14a-cmp.out Please split one test per line and sort. > endif > endif > endif > @@ -1521,6 +1521,8 @@ tst-auditmany-ENV = \ > LDFLAGS-tst-audit14 = -Wl,--audit=tst-auditlogmod-1.so > $(objpfx)tst-auditlogmod-1.so: $(libsupport) > $(objpfx)tst-audit14.out: $(objpfx)tst-auditlogmod-1.so > +LDFLAGS-tst-audit14a = -Wl,--audit=tst-auditlogmod-1.so,--enable-new-dtags > +$(objpfx)tst-audit14a.out: $(objpfx)tst-auditlogmod-1.so OK. > LDFLAGS-tst-audit15 = \ > -Wl,--audit=tst-auditlogmod-1.so,--depaudit=tst-auditlogmod-2.so > $(objpfx)tst-auditlogmod-2.so: $(libsupport) > @@ -1547,6 +1549,9 @@ tst-audit17-ENV = LD_AUDIT=$(objpfx)tst-auditmod17.so > $(objpfx)tst-audit14-cmp.out: tst-audit14.exp $(objpfx)tst-audit14.out > cmp $^ > $@; \ > $(evaluate-test) > +$(objpfx)tst-audit14a-cmp.out: tst-audit14.exp $(objpfx)tst-audit14a.out > + cmp $^ > $@; \ > + $(evaluate-test) OK. > $(objpfx)tst-audit15-cmp.out: tst-audit15.exp $(objpfx)tst-audit15.out > cmp $^ > $@; \ > $(evaluate-test) > diff --git a/elf/dl-load.c b/elf/dl-load.c > index bf8957e73c..1f424ea7c8 100644 > --- a/elf/dl-load.c > +++ b/elf/dl-load.c The preceding block is like this: 2146 /* When the object has the RUNPATH information we don't use any 2147 RPATHs. */ 2148 if (loader == NULL || loader->l_info[DT_RUNPATH] == NULL) 2149 { The entire design of this block is to look into DT_RPATH specifically under two conditions: (a) We don't know anything about the loading module, it is NULL, and therefore we don't know if DT_RUNPATH was present, which if it was present, would prevent the use of DT_RPATH. (b) We have a loader, and we know it doesn't have DT_RUNPATH and so we will look for DT_RPATH. Your changes adds (c) to this case in which DT_RUNPATH is used, and this seems to be logically distinct from the above two cases. My suggestion is that the code you are adding should be in a distinct block *after* the above block starting around line 2189. We already have a block like this: 2189 /* Look at the RUNPATH information for this binary. */ 2190 if (fd == -1 && loader != NULL 2191 && cache_rpath (loader, &loader->l_runpath_dirs, 2192 DT_RUNPATH, "RUNPATH")) 2193 fd = open_path (name, namelen, mode, 2194 &loader->l_runpath_dirs, &realname, &fb, loader, 2195 LA_SER_RUNPATH, &found_other_class); I think it is logically more correct to add to this DT_RUNPATH handling than ato add to the DT_RPATH handling above. So after this block you might add: /* When processing the lookup we may need to additionally try DT_RUNPATH in the executable for a glibc internal dlopen call when looking for audit modules. */ if (__glibc_unlikely (mode & __RTLD_AUDIT) && fd == -1) { ... } The hard part is that you may want to know a few things: (a) main_map (unavailable, but computable via GL(dl_ns)[LM_ID_BASE]._ns_loaded) (b) did_main_map (unavailable) * This seems like an optimization because if you already looked up via main_map and it failed, doing it twice won't help, so you can refactor did_main_map to function scope and retain the fact that you did this check already if you want to keep the optimization. Otherwise everything else is there to implement the fix. > @@ -2175,6 +2175,21 @@ _dl_map_object (struct link_map *loader, const char *name, > &main_map->l_rpath_dirs, > &realname, &fb, loader ?: main_map, LA_SER_RUNPATH, > &found_other_class); > + > + /* Also try DT_RUNPATH in the executable for glibc internal > + dlopen call. */ > + if (__glibc_unlikely (mode & __RTLD_AUDIT) > + && fd == -1 && !did_main_map > + && main_map != NULL && main_map->l_type != lt_loaded) > + { > + struct r_search_path_struct l_rpath_dirs; > + l_rpath_dirs.dirs = NULL; > + if (cache_rpath (main_map, &l_rpath_dirs, > + DT_RUNPATH, "RUNPATH")) > + fd = open_path (name, namelen, mode, &l_rpath_dirs, > + &realname, &fb, loader ?: main_map, > + LA_SER_RUNPATH, &found_other_class); > + } > } > > /* Try the LD_LIBRARY_PATH environment variable. */ > diff --git a/elf/tst-audit14a.c b/elf/tst-audit14a.c > new file mode 100644 > index 0000000000..c6232eacf2 > --- /dev/null > +++ b/elf/tst-audit14a.c > @@ -0,0 +1 @@ > +#include "tst-audit14.c" > -- Cheers, Carlos. ^ permalink raw reply [flat|nested] 8+ messages in thread
* Re: [PATCH v3 3/3] elf: Also try DT_RUNPATH for LD_AUDIT dlopen [BZ #28455] 2021-12-13 22:07 ` Carlos O'Donell @ 2021-12-16 2:07 ` H.J. Lu 0 siblings, 0 replies; 8+ messages in thread From: H.J. Lu @ 2021-12-16 2:07 UTC (permalink / raw) To: Carlos O'Donell; +Cc: GNU C Library On Mon, Dec 13, 2021 at 2:07 PM Carlos O'Donell <carlos@redhat.com> wrote: > > On 12/8/21 10:25, H.J. Lu wrote: > > DT_RUNPATH is only used to find the immediate dependencies of the > > executable or shared object containing the DT_RUNPATH entry. Update > > the glibc LD_AUDIT dlopen call to try the DT_RUNPATH entry of the > > executable. This partially fixes BZ #28455. > > Please post v4 split out. > > > --- > > elf/Makefile | 9 +++++++-- > > elf/dl-load.c | 15 +++++++++++++++ > > elf/tst-audit14a.c | 1 + > > 3 files changed, 23 insertions(+), 2 deletions(-) > > create mode 100644 elf/tst-audit14a.c > > > > diff --git a/elf/Makefile b/elf/Makefile > > index 4b5bdcb08e..aa6b24d790 100644 > > --- a/elf/Makefile > > +++ b/elf/Makefile > > @@ -247,10 +247,10 @@ ifneq ($(selinux-enabled),1) > > tests-execstack-yes = tst-execstack tst-execstack-needed tst-execstack-prog > > endif > > ifeq ($(have-depaudit),yes) > > -tests += tst-audit14 tst-audit15 tst-audit16 > > +tests += tst-audit14 tst-audit15 tst-audit16 tst-audit14a > > Please split one test per line and sort. Fixed. > > ifeq ($(run-built-tests),yes) > > tests-special += $(objpfx)tst-audit14-cmp.out $(objpfx)tst-audit15-cmp.out \ > > - $(objpfx)tst-audit16-cmp.out > > + $(objpfx)tst-audit16-cmp.out $(objpfx)tst-audit14a-cmp.out > > Please split one test per line and sort. Fixed. > > endif > > endif > > endif > > @@ -1521,6 +1521,8 @@ tst-auditmany-ENV = \ > > LDFLAGS-tst-audit14 = -Wl,--audit=tst-auditlogmod-1.so > > $(objpfx)tst-auditlogmod-1.so: $(libsupport) > > $(objpfx)tst-audit14.out: $(objpfx)tst-auditlogmod-1.so > > +LDFLAGS-tst-audit14a = -Wl,--audit=tst-auditlogmod-1.so,--enable-new-dtags > > +$(objpfx)tst-audit14a.out: $(objpfx)tst-auditlogmod-1.so > > OK. > > > LDFLAGS-tst-audit15 = \ > > -Wl,--audit=tst-auditlogmod-1.so,--depaudit=tst-auditlogmod-2.so > > $(objpfx)tst-auditlogmod-2.so: $(libsupport) > > @@ -1547,6 +1549,9 @@ tst-audit17-ENV = LD_AUDIT=$(objpfx)tst-auditmod17.so > > $(objpfx)tst-audit14-cmp.out: tst-audit14.exp $(objpfx)tst-audit14.out > > cmp $^ > $@; \ > > $(evaluate-test) > > +$(objpfx)tst-audit14a-cmp.out: tst-audit14.exp $(objpfx)tst-audit14a.out > > + cmp $^ > $@; \ > > + $(evaluate-test) > > OK. > > > $(objpfx)tst-audit15-cmp.out: tst-audit15.exp $(objpfx)tst-audit15.out > > cmp $^ > $@; \ > > $(evaluate-test) > > diff --git a/elf/dl-load.c b/elf/dl-load.c > > index bf8957e73c..1f424ea7c8 100644 > > --- a/elf/dl-load.c > > +++ b/elf/dl-load.c > > The preceding block is like this: > > 2146 /* When the object has the RUNPATH information we don't use any > 2147 RPATHs. */ > 2148 if (loader == NULL || loader->l_info[DT_RUNPATH] == NULL) > 2149 { > > The entire design of this block is to look into DT_RPATH specifically > under two conditions: > > (a) We don't know anything about the loading module, it is NULL, and > therefore we don't know if DT_RUNPATH was present, which if it > was present, would prevent the use of DT_RPATH. > > (b) We have a loader, and we know it doesn't have DT_RUNPATH and so > we will look for DT_RPATH. > > Your changes adds (c) to this case in which DT_RUNPATH is used, and > this seems to be logically distinct from the above two cases. > > My suggestion is that the code you are adding should be in a distinct > block *after* the above block starting around line 2189. > > We already have a block like this: > 2189 /* Look at the RUNPATH information for this binary. */ > 2190 if (fd == -1 && loader != NULL > 2191 && cache_rpath (loader, &loader->l_runpath_dirs, > 2192 DT_RUNPATH, "RUNPATH")) > 2193 fd = open_path (name, namelen, mode, > 2194 &loader->l_runpath_dirs, &realname, &fb, loader, > 2195 LA_SER_RUNPATH, &found_other_class); > > I think it is logically more correct to add to this DT_RUNPATH handling > than ato add to the DT_RPATH handling above. > > So after this block you might add: > > /* When processing the lookup we may need to additionally try DT_RUNPATH > in the executable for a glibc internal dlopen call when looking for > audit modules. */ > if (__glibc_unlikely (mode & __RTLD_AUDIT) > && fd == -1) > { > ... > } Fixed. > The hard part is that you may want to know a few things: > (a) main_map (unavailable, but computable via GL(dl_ns)[LM_ID_BASE]._ns_loaded) > (b) did_main_map (unavailable) > * This seems like an optimization because if you already looked up via > main_map and it failed, doing it twice won't help, so you can refactor > did_main_map to function scope and retain the fact that you did this > check already if you want to keep the optimization. Fixed. > Otherwise everything else is there to implement the fix. > Sent out the v4 patch. Thanks. -- H.J. ^ permalink raw reply [flat|nested] 8+ messages in thread
end of thread, other threads:[~2021-12-16 2:07 UTC | newest] Thread overview: 8+ messages (download: mbox.gz / follow: Atom feed) -- links below jump to the message on this page -- 2021-12-08 15:24 [PATCH v3 0/3] Properly handle DT_RUNPATH H.J. Lu 2021-12-08 15:24 ` [PATCH v3 1/3] Add and use link-test-modules-rpath-link [BZ #28455] H.J. Lu 2021-12-13 15:32 ` Carlos O'Donell 2021-12-08 15:25 ` [PATCH v3 2/3] Disable DT_RUNPATH on NSS tests " H.J. Lu 2021-12-13 15:29 ` Carlos O'Donell 2021-12-08 15:25 ` [PATCH v3 3/3] elf: Also try DT_RUNPATH for LD_AUDIT dlopen " H.J. Lu 2021-12-13 22:07 ` Carlos O'Donell 2021-12-16 2:07 ` H.J. Lu
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