From patchwork Tue May 22 18:40:54 2018 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 8bit X-Patchwork-Submitter: rcardoso@linux.vnet.ibm.com X-Patchwork-Id: 27406 Received: (qmail 71843 invoked by alias); 22 May 2018 18:41:25 -0000 Mailing-List: contact libc-alpha-help@sourceware.org; run by ezmlm Precedence: bulk List-Id: List-Unsubscribe: List-Subscribe: List-Archive: List-Post: List-Help: , Sender: libc-alpha-owner@sourceware.org Delivered-To: mailing list libc-alpha@sourceware.org Received: (qmail 71799 invoked by uid 89); 22 May 2018 18:41:22 -0000 Authentication-Results: sourceware.org; auth=none X-Virus-Found: No X-Spam-SWARE-Status: No, score=-26.5 required=5.0 tests=AWL, BAYES_00, GIT_PATCH_0, GIT_PATCH_1, GIT_PATCH_2, GIT_PATCH_3, KAM_LAZY_DOMAIN_SECURITY, KAM_SHORT, RCVD_IN_DNSWL_LOW autolearn=ham version=3.3.2 spammy= X-HELO: mx0a-001b2d01.pphosted.com Subject: Re: [RFC] powerpc: restore TOC when static longjmp to shared object References: To: libc-alpha@sourceware.org From: Rogerio Alves X-Forwarded-Message-Id: Date: Tue, 22 May 2018 15:40:54 -0300 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101 Thunderbird/52.4.0 MIME-Version: 1.0 In-Reply-To: X-TM-AS-GCONF: 00 x-cbid: 18052218-0004-0000-0000-00001422EC11 X-IBM-SpamModules-Scores: X-IBM-SpamModules-Versions: BY=3.00009067; HX=3.00000241; KW=3.00000007; PH=3.00000004; SC=3.00000261; SDB=6.01036126; UDB=6.00530024; IPR=6.00815254; MB=3.00021242; MTD=3.00000008; XFM=3.00000015; UTC=2018-05-22 18:41:15 X-IBM-AV-DETECTION: SAVI=unused REMOTE=unused XFE=unused x-cbparentid: 18052218-0005-0000-0000-0000874FD6F3 Message-Id: <4c67a306-d447-1158-1b92-22ed1cfcfa0a@linux.vnet.ibm.com> X-Proofpoint-Virus-Version: vendor=fsecure engine=2.50.10434:, , definitions=2018-05-22_06:, , signatures=0 X-Proofpoint-Spam-Details: rule=outbound_notspam policy=outbound score=0 priorityscore=1501 malwarescore=0 suspectscore=3 phishscore=0 bulkscore=0 spamscore=0 clxscore=1011 lowpriorityscore=0 impostorscore=0 adultscore=0 classifier=spam adjust=0 reason=mlx scancount=1 engine=8.0.1-1709140000 definitions=main-1805220197 I've attached patch v2 to this email with the fixes suggested by Adhemerval. One last issue is regard to the copyright on the tests. I put a copyright there but, the test is based on a test the user reported in bugzilla. I've adapted to libsupport and changed some of the code. What should I do in that case? I have to get the permission from the author first since the test is a derivative work? Some of the tests doesn't have copyright, and some of them mention the person who reports the test like stdio-common/tstscanf.c but I can't find a standard. Em 16-05-2018 21:42, libc-alpha-digest-help@sourceware.org escreveu: > > On 16/05/2018 16:36, Rogerio Alves wrote: >> Attached to this email I am sending the first version of the patch but I have a problem with this patch. I can't make the test work. By some reason it can't find the .so needed by the test: >> >> FAIL: >> ./setjmp-bug21895.so: cannot open shared object file: No such file or directory >> >> Notice that if I manually execute the command on make check stdout inside the folder it works fine. I'd appreciate any help on that. >> >> Regards >> >> Em 15-05-2018 17:48, Tulio Magno Quites Machado Filho escreveu: >>> Florian Weimer writes: >>> >>>> * Rogerio Alves: >>>> >>>>> One simple solution would be always restore the TOC pointer by uncomment >>>>> the line bellow: >>>>> >>>>> /*     std r2,FRAME_TOC_SAVE(r1)       Restore the TOC save area.  */ >>>>> >>>>> Or maybe we can check if we have a valid TOC pointer before restore it, >>>>> instead #if defined SHARED. >>>> Is the register reserved for the TOC pointer in static builds, too? >>>> Then I suggest to unconditionally save nad restore it; not doing so >>>> looks like a pointless micro-optimization. >>>> >>>> Another problem with sharing jump buffers across static dlopen is that >>>> you might not have identical pointer guard values. >>>> >>>>> I would like to request for comments on this matter: Should we fix/work >>>>> this? Is feasible to change longjmp to always restore TOC pointer? >>>> Does setjmp already save it unonditionally? >>>> >>>> Removal of static dlopen is still some time away; it's likely not >>>> going to happen in this cycle, and the fix looks simple enough. >>> If static dlopen is still going to be supported for some cycles, I also agree >>> it should be saved and restored unconditionally. >>> >> 0001-PATCH-v1-powerpc-Always-restore-TOC-on-longjmp.patch >> >> >> From eb9895f1548c8f6e1826095aee3221eaf9ce84c9 Mon Sep 17 00:00:00 2001 >> From: Rogerio Alves >> Date: Wed, 16 May 2018 14:20:53 -0500 >> Subject: [PATCH] [PATCH v1] powerpc: Always restore TOC on longjmp. >> >> This patch change longjmp to always restore the TOC pointer (r2 register) >> to the caller frame on powerpc. This is related to bug 21895[1] that reports >> a situation where you have a static longjmp to a shared object file. >> >> [1]https://sourceware.org/bugzilla/show_bug.cgi?id=21895 > Please indicate where you actually tested this patch (since the make check > is broken). > I've fixed the test thanks to your suggestion. >> 2018-05-16 Rogerio A. Cardoso >> >> *sysdeps/powerpc/powerpc64/__longjmp-common.S: Remove condition code for >> restore r2 on longjmp. >> *setjmp/Makefile: Include test build directives. > You need to add each rules you might add, the ones you are changing, and > removing (check other ChangeLog for example). > Done. >> *setjmp/setjmp-bug21895.c: new test file. >> *setjmp/tst-setjmp-bug21895.c: new test file. > Capitalize the new. > Done. >> --- >> setjmp/Makefile | 18 ++++++-- >> setjmp/setjmp-bug21895.c | 42 ++++++++++++++++++ >> setjmp/tst-setjmp-bug21895.c | 65 ++++++++++++++++++++++++++++ >> sysdeps/powerpc/powerpc64/__longjmp-common.S | 5 +-- >> 4 files changed, 123 insertions(+), 7 deletions(-) >> create mode 100644 setjmp/setjmp-bug21895.c >> create mode 100644 setjmp/tst-setjmp-bug21895.c >> >> diff --git a/setjmp/Makefile b/setjmp/Makefile >> index dc2fcc6..e715ee6 100644 >> --- a/setjmp/Makefile >> +++ b/setjmp/Makefile >> @@ -22,16 +22,28 @@ subdir := setjmp >> >> include ../Makeconfig >> >> -headers := setjmp.h bits/setjmp.h bits/setjmp2.h >> +headers := setjmp.h bits/setjmp.h bits/setjmp2.h bits/dlfcn.h dlfcn/dlfcn.h > Why does it require adding more headers here? This is meant be installed afaik > and I am not following the requirement here. > >> >> routines := setjmp sigjmp bsd-setjmp bsd-_setjmp \ >> longjmp __longjmp jmp-unwind >> >> tests := tst-setjmp jmpbug bug269-setjmp tst-setjmp-fp \ >> - tst-sigsetjmp tst-setjmp-static >> + tst-sigsetjmp tst-setjmp-static tst-setjmp-bug21895 >> + > Since the idea is test for static build I would recommend to follow the other > static naming, i.e, tst-setjmp-bug21895-static. > Done. Added static suffix. >> tests-static := tst-setjmp-static >> >> +modules-names = setjmp-bug21895 >> >> include ../Rules >> >> -$(objpfx)tst-setjmp-fp: $(libm) > I do not think you meant to remove this rule. > It was not removed I've write the new rules before this rule. Anyway I've fixed it on v2. >> +test-modules = $(addprefix $(objpfx),$(addsuffix .so,$(modules-names))) >> + >> +ifeq ($(build-shared),yes) >> +tests: $(test-modules) >> +endif >> + >> +$(objpfx)setjmp-bug21895.so: $(libdl) >> +$(objpfx)tst-setjmp-bug21895: $(libdl) >> +$(objpfx)tst-setjmp-bug21895.out: $(objpfx)setjmp-bug21895.so >> + >> +$(objpfx)ts-tsetjmp-fp: $(libm) > I think the idea is to build the test even if build-shared is set to no (since > you are testing static linking). I think what you want is: > > --- > > diff --git a/setjmp/Makefile b/setjmp/Makefile > index dc2fcc6..231474b 100644 > --- a/setjmp/Makefile > +++ b/setjmp/Makefile > @@ -28,10 +28,17 @@ routines := setjmp sigjmp bsd-setjmp bsd-_setjmp \ > longjmp __longjmp jmp-unwind > > tests := tst-setjmp jmpbug bug269-setjmp tst-setjmp-fp \ > - tst-sigsetjmp tst-setjmp-static > -tests-static := tst-setjmp-static > + tst-sigsetjmp tst-setjmp-static tst-setjmp-bug21895-static > > +tests-static := tst-setjmp-static tst-setjmp-bug21895-static > + > +modules-names = setjmp-bug21895 > > include ../Rules > > $(objpfx)tst-setjmp-fp: $(libm) > +$(objpfx)tst-setjmp-bug21895-static: $(common-objpfx)dlfcn/libdl.a > +$(objpfx)tst-setjmp-bug21895-static.out: $(objpfx)setjmp-bug21895.so > + > +tst-setjmp-bug21895-static-ENV = \ > + LD_LIBRARY_PATH=$(objpfx):$(common-objpfx):$(common-objpfx)setjmp:$(common-objpfx)elf > > --- > > At least with qemu-static it seems to work with your patch. > > Thanks to your help it's working now. That's exactly what I wanted. >> diff --git a/setjmp/setjmp-bug21895.c b/setjmp/setjmp-bug21895.c >> new file mode 100644 >> index 0000000..d6f5516 >> --- /dev/null >> +++ b/setjmp/setjmp-bug21895.c >> @@ -0,0 +1,42 @@ >> +/* Copyright (C) 2013-2018 Free Software Foundation, Inc. > Wrong Copyright date span and missing one line description. > Fixed. >> + 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 >> +. */ >> + >> +/* Test that setjmp/longjmp interoperability with static dlopen. >> + Bugzila #21895. */ >> +#include >> +#include >> +#include >> + >> +jmp_buf jb; >> +void (*bar)(jmp_buf); >> + >> +void >> +lbar (int i, ...) >> +{ >> + bar(jb); >> + for(;;); >> +} >> + >> +void >> +foo (void) >> +{ >> + int i = setjmp(jb); >> + char *c = alloca(256); >> + memset(c, 0, 256); >> + lbar(i); >> + for(;;); >> +} >> diff --git a/setjmp/tst-setjmp-bug21895.c b/setjmp/tst-setjmp-bug21895.c >> new file mode 100644 >> index 0000000..5333494 >> --- /dev/null >> +++ b/setjmp/tst-setjmp-bug21895.c >> @@ -0,0 +1,65 @@ >> +/* Copyright (C) 2013-2018 Free Software Foundation, Inc. > Wrong Copyright date span and missing one line description. > Fixed. >> + 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 >> +. */ >> + >> +/* Test that setjmp/longjmp interoperability with static dlopen. >> + Bugzila #21895. */ >> + >> +#include >> +#include >> +#include >> +#include >> + >> +static void >> +bar (jmp_buf jb) >> +{ >> + static int i; >> + if (i++==1) exit(0); >> + longjmp(jb, i); >> +} >> + >> +static int >> +do_test (void) >> +{ >> + void *h = dlopen("./setjmp-bug21895.so", RTLD_NOW); > Better to just use name, since on test environment variable in Makefile > change I proposed the path to build setjmp folder is already on the > LD_LIBRARY_PATH list. > >> + if (!h) { >> + puts ("FAIL: "); >> + puts (dlerror()); >> + return 1; >> + } > Wrong indentation and please use libsupport macros. > Fixed. Using libsupport now. >> + >> + void (*pfoo)(void) = dlsym(h, "foo"); >> + if (!pfoo) { >> + puts ("FAIL: "); >> + puts (dlerror()); >> + return 1; >> + } >> + >> + void (**ppbar)(jmp_buf) = dlsym(h, "bar"); >> + if (!ppbar) { >> + puts ("FAIL: "); >> + puts (dlerror()); >> + return 1; >> + } >> + >> + *ppbar = bar; >> + pfoo(); >> + >> + for(;;); >> +} >> + >> +#define TEST_FUNCTION do_test () >> +#include "../test-skeleton.c" > We do not use test-skeleton.c inclusion any longer, use libsupport > (support/test-driver.c). > Done. >> diff --git a/sysdeps/powerpc/powerpc64/__longjmp-common.S b/sysdeps/powerpc/powerpc64/__longjmp-common.S >> index 0e10b8d..a5973c9 100644 >> --- a/sysdeps/powerpc/powerpc64/__longjmp-common.S >> +++ b/sysdeps/powerpc/powerpc64/__longjmp-common.S >> @@ -130,9 +130,6 @@ L(no_vmx): >> ld r0,(JB_LR*8)(r3) >> ld r14,((JB_GPRS+0)*8)(r3) >> lfd fp14,((JB_FPRS+0)*8)(r3) >> -#if defined SHARED && !IS_IN (rtld) >> - std r2,FRAME_TOC_SAVE(r1) /* Restore the callers TOC save area. */ >> -#endif >> ld r15,((JB_GPRS+1)*8)(r3) >> lfd fp15,((JB_FPRS+1)*8)(r3) >> ld r16,((JB_GPRS+2)*8)(r3) >> @@ -152,7 +149,7 @@ L(no_vmx): >> second argument (-4@4), and target address (8@0), respectively. */ >> LIBC_PROBE (longjmp, 3, 8@3, -4@4, 8@0) >> mtlr r0 >> -/* std r2,FRAME_TOC_SAVE(r1) Restore the TOC save area. */ >> + std r2,FRAME_TOC_SAVE(r1) /* Restore the TOC save area. */ > Space before tab in indent. > Done. >> ld r21,((JB_GPRS+7)*8)(r3) >> lfd fp21,((JB_FPRS+7)*8)(r3) >> ld r22,((JB_GPRS+8)*8)(r3) >> -- 2.7.4 >> From 989f90132a77d8f1199881d88f51384f25d452fb Mon Sep 17 00:00:00 2001 From: Rogerio Alves Date: Wed, 16 May 2018 14:20:53 -0500 Subject: [PATCH v2] powerpc: Always restore TOC on longjmp. This patch change longjmp to always restore the TOC pointer (r2 register) to the caller frame on powerpc. This is related to bug 21895[1] that reports a situation where you have a static longjmp to a shared object file. [1] https://sourceware.org/bugzilla/show_bug.cgi?id=21895 2018-05-16 Rogerio A. Cardoso *sysdeps/powerpc/powerpc64/__longjmp-common.S: Remove condition code for restore r2 on longjmp. *setjmp/Makefile: Added tst-setjmp-bug21895-static to test list. Added rules to build test tst-setjmp-bug21895-static Added module setjmp-bug21895 and rules to build a shared object from it. *setjmp/setjmp-bug21895.c: New test file. *setjmp/tst-setjmp-bug21895-static.c: New test file. --- Changes in v2: Per Adhemerval Zanella. Fix test fail using the suggestions given. Fix changelog. Fix copyright and indentation for new tests. Change tests to use libsupport instead old test-skeleton. Fix a extra space in __longjmp-common. setjmp/Makefile | 16 ++++++- setjmp/setjmp-bug21895.c | 44 ++++++++++++++++++ setjmp/tst-setjmp-bug21895-static.c | 67 ++++++++++++++++++++++++++++ sysdeps/powerpc/powerpc64/__longjmp-common.S | 5 +-- 4 files changed, 127 insertions(+), 5 deletions(-) create mode 100644 setjmp/setjmp-bug21895.c create mode 100644 setjmp/tst-setjmp-bug21895-static.c diff --git a/setjmp/Makefile b/setjmp/Makefile index dc2fcc6..d70daa2 100644 --- a/setjmp/Makefile +++ b/setjmp/Makefile @@ -29,9 +29,23 @@ routines := setjmp sigjmp bsd-setjmp bsd-_setjmp \ tests := tst-setjmp jmpbug bug269-setjmp tst-setjmp-fp \ tst-sigsetjmp tst-setjmp-static -tests-static := tst-setjmp-static +tests-static := tst-setjmp-static tst-setjmp-bug21895-static + +modules-names = setjmp-bug21895 include ../Rules $(objpfx)tst-setjmp-fp: $(libm) + +test-modules = $(addprefix $(objpfx),$(addsuffix .so,$(modules-names))) + +ifeq ($(build-shared),yes) +tests: $(test-modules) +endif + +$(objpfx)tst-setjmp-bug21895-static: $(common-objpfx)dlfcn/libdl.a +$(objpfx)tst-setjmp-bug21895-static.out: $(objpfx)setjmp-bug21895.so + +tst-setjmp-bug21895-static-ENV = \ + LD_LIBRARY_PATH=$(objpfx):$(common-objpfx):$(common-objpfx)setjmp:$(common-objpfx)elf diff --git a/setjmp/setjmp-bug21895.c b/setjmp/setjmp-bug21895.c new file mode 100644 index 0000000..f8f3016 --- /dev/null +++ b/setjmp/setjmp-bug21895.c @@ -0,0 +1,44 @@ +/* Shared object part of test for setjmp interoperability with static + dlopen BZ #21895. + Copyright (C) 2017-2018 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 + . */ + +#include +#include +#include + +jmp_buf jb; +void (*bar)(jmp_buf); + +void +lbar (int i, ...) +{ + bar(jb); + for(;;); +} + +void +foo (void) +{ + int i = setjmp(jb); + char *c = alloca(256); + memset(c, 0, 256); + + lbar(i); + + for(;;); +} diff --git a/setjmp/tst-setjmp-bug21895-static.c b/setjmp/tst-setjmp-bug21895-static.c new file mode 100644 index 0000000..5338499 --- /dev/null +++ b/setjmp/tst-setjmp-bug21895-static.c @@ -0,0 +1,67 @@ +/* Test setjmp interoperability with static dlopen BZ #21895. + Copyright (C) 2017-2018 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 + . */ + +#include +#include +#include +#include + +static void +bar (jmp_buf jb) +{ + static int i; + if (i++==1) + exit(0); /* Success. */ + + longjmp(jb, i); +} + +static int +do_test (void) +{ + void *h = dlopen("setjmp-bug21895.so", RTLD_NOW); + if (!h) + { + puts(dlerror()); + return 1; + } + + void (*pfoo)(void) = dlsym(h, "foo"); + if (!pfoo) + { + puts(dlerror()); + return 1; + } + + void (**ppbar)(jmp_buf) = dlsym(h, "bar"); + if (!ppbar) + { + puts(dlerror()); + return 1; + } + + *ppbar = bar; + pfoo(); + + for(;;); +} + +/* Make sure the test will not stuck if jmp fails and fall into one of + for(;;). */ +#define TIMEOUT 100 +#include diff --git a/sysdeps/powerpc/powerpc64/__longjmp-common.S b/sysdeps/powerpc/powerpc64/__longjmp-common.S index 0e10b8d..99c17c5 100644 --- a/sysdeps/powerpc/powerpc64/__longjmp-common.S +++ b/sysdeps/powerpc/powerpc64/__longjmp-common.S @@ -130,9 +130,6 @@ L(no_vmx): ld r0,(JB_LR*8)(r3) ld r14,((JB_GPRS+0)*8)(r3) lfd fp14,((JB_FPRS+0)*8)(r3) -#if defined SHARED && !IS_IN (rtld) - std r2,FRAME_TOC_SAVE(r1) /* Restore the callers TOC save area. */ -#endif ld r15,((JB_GPRS+1)*8)(r3) lfd fp15,((JB_FPRS+1)*8)(r3) ld r16,((JB_GPRS+2)*8)(r3) @@ -152,7 +149,7 @@ L(no_vmx): second argument (-4@4), and target address (8@0), respectively. */ LIBC_PROBE (longjmp, 3, 8@3, -4@4, 8@0) mtlr r0 -/* std r2,FRAME_TOC_SAVE(r1) Restore the TOC save area. */ + std r2,FRAME_TOC_SAVE(r1) /* Restore the TOC save area. */ ld r21,((JB_GPRS+7)*8)(r3) lfd fp21,((JB_FPRS+7)*8)(r3) ld r22,((JB_GPRS+8)*8)(r3) -- 2.7.4