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2023-01-16Update copyright years.Jakub Jelinek1-1/+1
2022-10-17x86: Check corrupted return address when unwinding stackH.J. Lu1-2/+2
If shadow stack is enabled, when unwinding stack, we count how many stack frames we pop to reach the landing pad and adjust shadow stack by the same amount. When counting the stack frame, we compare the return address on normal stack against the return address on shadow stack. If they don't match, return _URC_FATAL_PHASE2_ERROR for the corrupted return address on normal stack. Don't check the return address for 1. Non-catchable exception where exception_class == 0. Process will be terminated. 2. Zero return address which marks the outermost stack frame. 3. Signal stack frame since kernel puts a restore token on shadow stack. * unwind-generic.h (_Unwind_Frames_Increment): Add the EXC argument. * unwind.inc (_Unwind_RaiseException_Phase2): Pass EXC to _Unwind_Frames_Increment. (_Unwind_ForcedUnwind_Phase2): Likewise. * config/i386/shadow-stack-unwind.h (_Unwind_Frames_Increment): Take the EXC argument. Return _URC_FATAL_PHASE2_ERROR if the return address on normal stack doesn't match the return address on shadow stack.
2022-01-03Update copyright years.Jakub Jelinek1-1/+1
2021-11-11libgcc: Fix backtrace fallback on PowerPC Big-endianRaphael Moreira Zinsly1-2/+3
At the end of the backtrace stream _Unwind_Find_FDE() may not be able to find the frame unwind info and will later call the backtrace fallback instead of finishing. This occurs when using an old libc on ppc64 due to dl_iterate_phdr() not being able to set the fde in the last trace. When this occurs the cfa of the trace will be behind of context's cfa. Also, libgo’s probestackmaps() calls the backtrace with a null pointer and can get to the backchain fallback with the same problem, in this case we are only interested in find a stack map, we don't need nor can do a backchain. _Unwind_ForcedUnwind_Phase2() can hit the same issue as it uses uw_frame_state_for(), so we need to treat _URC_NORMAL_STOP. libgcc/ChangeLog: PR libgcc/103044 * config/rs6000/linux-unwind.h (ppc_backchain_fallback): Check if it's called with a null argument or at the end of the backtrace and return. * unwind.inc (_Unwind_ForcedUnwind_Phase2): Treat _URC_NORMAL_STOP.
2021-10-14libgcc: Add a backchain fallback to _Unwind_Backtrace() on PowerPCRaphael Moreira Zinsly1-2/+12
Without dwarf2 unwind tables available _Unwind_Backtrace() is not able to return the full backtrace. This patch adds a fallback function on powerpc to get the backtrace by doing a backchain, this code was originally at glibc. libgcc/ChangeLog: * config/rs6000/linux-unwind.h (struct rt_sigframe): Move it to outside of get_regs() in order to use it in another function, this is done twice: for __powerpc64__ and for !__powerpc64__. (struct trace_arg): New struct. (struct layout): New struct. (ppc_backchain_fallback): New function. * unwind.inc (_Unwind_Backtrace): Look for _URC_NORMAL_STOP code state and call MD_BACKCHAIN_FALLBACK. gcc/testsuite/ChangeLog: * gcc.target/powerpc/unwind-backchain.c: New test.
2021-01-04Update copyright years.Jakub Jelinek1-1/+1
2020-01-01Update copyright years.Jakub Jelinek1-1/+1
From-SVN: r279813
2019-01-01Update copyright years.Jakub Jelinek1-1/+1
From-SVN: r267494
2018-04-19libgcc/CET: Skip signal frames when unwinding shadow stackH.J. Lu1-2/+2
When -fcf-protection -mcet is used, I got FAIL: g++.dg/eh/sighandle.C (gdb) bt #0 _Unwind_RaiseException (exc=exc@entry=0x416ed0) at /export/gnu/import/git/sources/gcc/libgcc/unwind.inc:140 #1 0x00007ffff7d9936b in __cxxabiv1::__cxa_throw (obj=<optimized out>, tinfo=0x403dd0 <typeinfo for int@@CXXABI_1.3>, dest=0x0) at /export/gnu/import/git/sources/gcc/libstdc++-v3/libsupc++/eh_throw.cc:90 #2 0x0000000000401255 in sighandler (signo=11, si=0x7fffffffd6f8, uc=0x7fffffffd5c0) at /export/gnu/import/git/sources/gcc/gcc/testsuite/g++.dg/eh/sighandle.C:9 #3 <signal handler called> <<<< Signal frame which isn't on shadow stack #4 dosegv () at /export/gnu/import/git/sources/gcc/gcc/testsuite/g++.dg/eh/sighandle.C:14 #5 0x00000000004012e3 in main () at /export/gnu/import/git/sources/gcc/gcc/testsuite/g++.dg/eh/sighandle.C:30 (gdb) p frames $6 = 5 (gdb) frame count should be 4, not 5. This patch skips signal frames when unwinding shadow stack. gcc/testsuite/ PR libgcc/85334 * g++.dg/torture/pr85334.C: New test. libgcc/ PR libgcc/85334 * unwind-generic.h (_Unwind_Frames_Increment): New. * config/i386/shadow-stack-unwind.h (_Unwind_Frames_Increment): Likewise. * unwind.inc (_Unwind_RaiseException_Phase2): Increment frame count with _Unwind_Frames_Increment. (_Unwind_ForcedUnwind_Phase2): Likewise. From-SVN: r259502
2018-01-03Update copyright years.Jakub Jelinek1-1/+1
From-SVN: r256169
2017-11-17Add Intel CET support for EH in libgcc.Igor Tsimbalist1-11/+23
Control-flow Enforcement Technology (CET), published by Intel, introduces the Shadow Stack feature, which ensures a return from a function is done to exactly the same location from where the function was called. When EH is present the control-flow transfer may skip some stack frames and the shadow stack has to be adjusted not to signal a violation of a control-flow transfer. It's done by counting a number of skiping frames and adjasting shadow stack pointer by this number. Having new semantic of the 'ret' instruction if CET is supported in HW the 'ret' instruction cannot be generated in ix86_expand_epilogue when we are returning after EH is processed. Added a code in ix86_expand_epilogue to adjust Shadow Stack pointer and to generate an indirect jump instead of 'ret'. As sp register is used during this adjustment thus the argument in pro_epilogue_adjust_stack is changed to update cfa_reg based on whether control-flow instrumentation is set. Without updating the cfa_reg field there is an assert later in dwarf2 pass related to mismatch the stack register and cfa_reg value. gcc/ * config/i386/i386.c (ix86_expand_epilogue): Change simple return to indirect jump for EH return if control-flow protection is enabled. Change explicit 'false' argument in pro_epilogue_adjust_stack with a value of flag_cf_protection. * config/i386/i386.md (simple_return_indirect_internal): Remove SImode restriction to support 64-bit. libgcc/ * config/i386/linux-unwind.h: Include config/i386/shadow-stack-unwind.h. * config/i386/shadow-stack-unwind.h: New file. * unwind-dw2.c: (uw_install_context): Add a frame parameter and pass it to _Unwind_Frames_Extra. * unwind-generic.h (_Unwind_Frames_Extra): New. * unwind.inc (_Unwind_RaiseException_Phase2): Add frames_p parameter. Add local variable frames to count number of frames. (_Unwind_ForcedUnwind_Phase2): Likewise. (_Unwind_RaiseException): Add local variable frames to count number of frames, pass it to _Unwind_RaiseException_Phase2 and uw_install_context. (_Unwind_ForcedUnwind): Likewise. (_Unwind_Resume): Likewise. (_Unwind_Resume_or_Rethrow): Likewise. From-SVN: r254876
2017-01-01Update copyright years.Jakub Jelinek1-1/+1
From-SVN: r243994
2016-01-04Update copyright years.Jakub Jelinek1-1/+1
From-SVN: r232055
2015-01-05Update copyright years.Jakub Jelinek1-1/+1
From-SVN: r219188
2014-01-02Update copyright years in libgcc/Richard Sandiford1-1/+1
From-SVN: r206295
2013-02-04Update copyright in libgcc.Richard Sandiford1-1/+1
From-SVN: r195731
2011-08-05Makefile.in (UNWIND_H): Remove.Rainer Orth1-0/+307
gcc: * Makefile.in (UNWIND_H): Remove. (LIB2ADDEH, LIB2ADDEHSTATIC, LIB2ADDEHSHARED): Move to ../libgcc/Makefile.in. (LIBUNWIND, SHLIBUNWIND_LINK, SHLIBUNWIND_INSTALL): Likewise. (LIBUNWINDDEP): Remove. (libgcc-support): Remove LIB2ADDEH, $(srcdir)/emutls.c dependencies. (libgcc.mvars): Remove LIB2ADDEH, LIB2ADDEHSTATIC, LIB2ADDEHSHARED, LIBUNWIND, SHLIBUNWIND_LINK, SHLIBUNWIND_INSTALL. (stmp-int-hdrs): Remove $(UNWIND_H) dependency. Don't copy $(UNWIND_H). * config.gcc (ia64*-*-linux*): Remove with_system_libunwind handling. * configure.ac (GCC_CHECK_UNWIND_GETIPINFO): Remove. * aclocal.m4: Regenerate. * configure: Regenerate. * emutls.c, unwind-c.c, unwind-compat.c, unwind-compat.h, unwind-dw2-fde-compat.c, unwind-dw2-fde-glibc.c, unwind-dw2-fde.c, unwind-dw2-fde.h, unwind-dw2.c, unwind-dw2.h, unwind-generic.h, unwind-pe.h, unwind-sjlj.c, unwind.inc: Move to ../libgcc. * unwind-dw2-fde-darwin.c: Move to ../libgcc/config. * config/arm/libunwind.S, config/arm/pr-support.c, config/arm/unwind-arm.c, config/arm/unwind-arm.h: Move to ../libgcc/config/arm. * config/arm/t-bpabi (UNWIND_H, LIB2ADDEH): Remove. * config/arm/t-symbian (UNWIND_H, LIB2ADDEH): Remove. * config/frv/t-frv ($(T)frvbegin$(objext)): Use $(srcdir)/../libgcc to refer to unwind-dw2-fde.h. ($(T)frvend$(objext)): Likewise. * config/ia64/t-glibc (LIB2ADDEH): Remove. * config/ia64/t-glibc-libunwind: Move to ../libgcc/config/ia64. * config/ia64/fde-glibc.c, config/ia64/fde-vms.c, config/ia64/unwind-ia64.c, config/ia64/unwind-ia64.h: Move to ../libgcc/config/ia64. * config/ia64/t-hpux (LIB2ADDEH): Remove. * config/ia64/t-ia64 (LIB2ADDEH): Remove. * config/ia64/t-vms (LIB2ADDEH): Remove. * config/ia64/vms.h (UNW_IVMS_MODE, MD_UNW_COMPATIBLE_PERSONALITY_P): Remove. * config/picochip/t-picochip (LIB2ADDEH): Remove. * config/rs6000/aix.h (R_LR, MD_FROB_UPDATE_CONTEXT): Remove. * config/rs6000/t-darwin (LIB2ADDEH): Remove. * config/rs6000/darwin-fallback.c: Move to ../libgcc/config/rs6000. * config/sh/t-sh ($(T)unwind-dw2-Os-4-200.o): Use $(srcdir)/../libgcc to refer to unwinder sources. * config/spu/t-spu-elf (LIB2ADDEH): Remove. * config/t-darwin (LIB2ADDEH): Remove. * config/t-freebsd (LIB2ADDEH): Remove. * config/t-libunwind (LIB2ADDEH, LIB2ADDEHSTATIC): Remove. * config/t-libunwind-elf: Move to ../libgcc/config. * config/t-linux (LIB2ADDEH): Remove. * config/t-sol2 (LIB2ADDEH): Remove. * config/xtensa/t-xtensa (LIB2ADDEH): Remove. * system.h (MD_FROB_UPDATE_CONTEXT): Poison. gcc/po: * EXCLUDES (unwind-c.c, unwind-dw2-fde-darwin.c) (unwind-dw2-fde-glibc.c, unwind-dw2-fde.c, unwind-dw2-fde.h) (unwind-dw2.c, unwind-pe.h, unwind-sjlj.c, unwind.h): Remove. libgcc: * Makefile.in (LIB2ADDEH, LIB2ADDEHSTATIC, LIB2ADDEHSHARED): New variables. (LIBUNWIND, SHLIBUNWIND_LINK, SHLIBUNWIND_INSTALL): New variables. (LIB2ADDEH, LIB2ADDEHSTATIC, LIB2ADDEHSHARED): Add $(srcdir)/emutls.c. (install-unwind_h): New target. (all): Depend on it. * config.host (unwind_header): New variable. (*-*-freebsd*): Set tmake_file to t-eh-dw2-dip. (*-*-linux*, frv-*-*linux*, *-*-kfreebsd*-gnu, *-*-knetbsd*-gnu, *-*-gnu*): Likewise, also for *-*-kopensolaris*-gnu. (*-*-solaris2*): Add t-eh-dw2-dip to tmake_file. (arm*-*-linux*): Add arm/t-bpabi for arm*-*-linux-*eabi. Set unwind_header. (arm*-*-uclinux*): Add arm/t-bpabi for arm*-*-uclinux*eabi. Set unwind_header. (arm*-*-eabi*, arm*-*-symbianelf*): Add arm/t-bpabi for arm*-*-eabi*. Add arm/t-symbian to tmake_file for arm*-*-symbianelf*. Set unwind_header. (ia64*-*-elf*): Add ia64/t-eh-ia64 to tmake_file. (ia64*-*-freebsd*): Likewise. (ia64*-*-linux*): Add ia64/t-glibc, ia64/t-eh-ia64, t-libunwind to tmake_file. Add t-libunwind-elf, ia64/t-glibc-libunwind unless $with_system_libunwind. (ia64*-*-hpux*): Set tmake_file. (ia64-hp-*vms*): Add ia64/t-eh-ia64 to tmake_file. (picochip-*-*): Set tmake_file. (rs6000-ibm-aix4.[3456789]*, powerpc-ibm-aix4.[3456789]*): Set md_unwind_header. (rs6000-ibm-aix5.1.*, powerpc-ibm-aix5.1.*): Likewise. (rs6000-ibm-aix[56789].*, powerpc-ibm-aix[56789].*): Likewise. (s390x-ibm-tpf*): Add t-eh-dw2-dip to tmake_file. (xtensa*-*-elf*): Set tmake_file. (xtensa*-*-linux*): Likewise. * configure.ac: Include ../config/unwind_ipinfo.m4. Call GCC_CHECK_UNWIND_GETIPINFO. Link unwind.h to $unwind_header. * configure: Regenerate. * emutls.c, unwind-c.c, unwind-compat.c, unwind-compat.h, unwind-dw2-fde-compat.c, unwind-dw2-fde-dip.c, unwind-dw2-fde.c, unwind-dw2-fde.h, unwind-dw2.c, unwind-dw2.h, unwind-generic.h, unwind-pe.h, unwind-sjlj.c, unwind.inc: New files. * config/unwind-dw2-fde-darwin.c: New file. * config/arm/libunwind.S, config/arm/pr-support.c, config/arm/t-bpabi, config/arm/t-symbian, config/arm/unwind-arm.c, config/arm/unwind-arm.h,: New files. * config/ia64/fde-glibc.c, config/ia64/fde-vms.c, config/ia64/t-eh-ia64, config/ia64/t-glibc, config/ia64/t-glibc-libunwind, config/ia64/t-hpux, config/ia64/t-vms, config/ia64/unwind-ia64.c, config/ia64/unwind-ia64.h: New files. * config/picochip/t-picochip: New file. * config/rs6000/aix-unwind.h, config/rs6000/darwin-fallback.c: New files. * config/rs6000/t-darwin (LIB2ADDEH): Set. * config/s390/t-tpf (LIB2ADDEH): Remove. * config/t-darwin (LIB2ADDEH): Set. * config/t-eh-dw2-dip: New file. * config/t-libunwind, config/t-libunwind-elf: New files. * config/t-sol2 (LIB2ADDEH): Remove. * config/xtensa/t-xtensa: New file. gcc/ada: * gcc-interface/Makefile.in (raise-gcc.o): Search $(srcdir)/../libgcc. libgo: * Makefile.am (AM_CFLAGS): Search $(srcdir)/../libgcc. * Makefile.in: Regenerate. libjava: * configure.ac (GCC_UNWIND_INCLUDE): Rename to LIBGCC_UNWIND_INCLUDE. Point to $(multi_basedir)/./libjava/../libgcc. * configure: Regenerate. * Makefile.am (GCC_UNWIND_INCLUDE): Reflect this. * Makefile.in: Regenerate. libobjc: * Makefile.in (INCLUDES): Search $(srcdir)/$(MULTISRCTOP)../libgcc. libstdc++-v3: * acinclude.m4 (GLIBCXX_EXPORT_INCLUDES): Point TOPLEVEL_INCLUDES to $(toplevel_srcdir)/libgcc. * configure: Regenerate. From-SVN: r177447