Message ID | ee96e132dc4218741552c1220f9b81af3084f9e9.1613577607.git.fweimer@redhat.com |
---|---|
State | New |
Headers | show |
Series | Unwinder interface consolidation | expand |
On 2/17/21 11:02 AM, Florian Weimer via Libc-alpha wrote: > This will be used to consolidate the libgcc_s access for backtrace > and pthread_cancel. > > Unlike the existing backtrace implementations, it provides some > hardening based on pointer mangling. LGTM. Creates unwind-link.h framework. Adds __libc_unwind_link_get@@GLIBC_PRIVATE for use by libpthread. Reviewed-by: Carlos O'Donell <carlos@redhat.com> > --- > debug/backtrace.c | 2 +- > malloc/set-freeres.c | 5 + > misc/Makefile | 2 +- > misc/Versions | 1 + > misc/unwind-link.c | 145 ++++++++++++++++++ > sysdeps/alpha/unwind-arch.h | 28 ++++ > sysdeps/arm/unwind-arch.h | 35 +++++ > sysdeps/generic/unwind-arch.h | 27 ++-- > sysdeps/generic/unwind-link.h | 106 +++++++++++++ > sysdeps/i386/unwind-arch.h | 39 +++++ > sysdeps/ia64/unwind-arch.h | 32 ++++ > sysdeps/m68k/m680x0/unwind-arch.h | 26 ++++ > sysdeps/m68k/unwind-arch.h | 35 +++++ > sysdeps/mach/hurd/fork.c | 3 + > .../{unix/sysv/linux => }/mips/unwind-arch.h | 17 +- > sysdeps/nptl/fork.c | 3 + > sysdeps/powerpc/powerpc32/unwind-arch.h | 28 ++++ > sysdeps/s390/unwind-arch.h | 28 ++++ > sysdeps/sh/unwind-arch.h | 28 ++++ > sysdeps/sparc/unwind-arch.h | 28 ++++ > 20 files changed, 600 insertions(+), 18 deletions(-) > create mode 100644 misc/unwind-link.c > create mode 100644 sysdeps/alpha/unwind-arch.h > create mode 100644 sysdeps/arm/unwind-arch.h > create mode 100644 sysdeps/generic/unwind-link.h > create mode 100644 sysdeps/i386/unwind-arch.h > create mode 100644 sysdeps/ia64/unwind-arch.h > create mode 100644 sysdeps/m68k/m680x0/unwind-arch.h > create mode 100644 sysdeps/m68k/unwind-arch.h > rename sysdeps/{unix/sysv/linux => }/mips/unwind-arch.h (85%) > create mode 100644 sysdeps/powerpc/powerpc32/unwind-arch.h > create mode 100644 sysdeps/s390/unwind-arch.h > create mode 100644 sysdeps/sh/unwind-arch.h > create mode 100644 sysdeps/sparc/unwind-arch.h > > diff --git a/debug/backtrace.c b/debug/backtrace.c > index 9449c51f06..5ded57bfc4 100644 > --- a/debug/backtrace.c > +++ b/debug/backtrace.c > @@ -23,7 +23,7 @@ > #include <gnu/lib-names.h> > #include <stdlib.h> > #include <unwind.h> > -#include <unwind-arch.h> > +#include <unwind-link.h> > > struct trace_arg > { > diff --git a/malloc/set-freeres.c b/malloc/set-freeres.c > index 24c7194aa8..817fbea8b8 100644 > --- a/malloc/set-freeres.c > +++ b/malloc/set-freeres.c > @@ -19,6 +19,7 @@ > #include <stdlib.h> > #include <set-hooks.h> > #include <libc-internal.h> > +#include <unwind-link.h> > > #include "../nss/nsswitch.h" > #include "../libio/libioP.h" > @@ -61,6 +62,10 @@ __libc_freeres (void) > if (&__libpthread_freeres != NULL) > __libpthread_freeres (); > > +#ifdef SHARED > + __libc_unwind_link_freeres (); > +#endif > + > for (p = symbol_set_first_element (__libc_freeres_ptrs); > !symbol_set_end_p (__libc_freeres_ptrs, p); ++p) > free (*p); > diff --git a/misc/Makefile b/misc/Makefile > index b08d7c68ab..cfc15355d6 100644 > --- a/misc/Makefile > +++ b/misc/Makefile > @@ -73,7 +73,7 @@ routines := brk sbrk sstk ioctl \ > fgetxattr flistxattr fremovexattr fsetxattr getxattr \ > listxattr lgetxattr llistxattr lremovexattr lsetxattr \ > removexattr setxattr getauxval ifunc-impl-list makedev \ > - allocate_once fd_to_filename single_threaded > + allocate_once fd_to_filename single_threaded unwind-link > > generated += tst-error1.mtrace tst-error1-mem.out \ > tst-allocate_once.mtrace tst-allocate_once-mem.out > diff --git a/misc/Versions b/misc/Versions > index 95666f6548..d5b348e83a 100644 > --- a/misc/Versions > +++ b/misc/Versions > @@ -172,5 +172,6 @@ libc { > __mmap; __munmap; __mprotect; > __sched_get_priority_min; __sched_get_priority_max; > __libc_allocate_once_slow; > + __libc_unwind_link_get; > } > } > diff --git a/misc/unwind-link.c b/misc/unwind-link.c > new file mode 100644 > index 0000000000..ad3d02bf32 > --- /dev/null > +++ b/misc/unwind-link.c > @@ -0,0 +1,145 @@ > +/* Dynamic loading of the libgcc unwinder. > + 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/>. */ > + > +#ifdef SHARED > + > +#include <assert.h> > +#include <dlfcn.h> > +#include <gnu/lib-names.h> > +#include <unwind-link.h> > +#include <libc-lock.h> > + > +/* Statically allocate the object, so that we do not have to deal with > + malloc failure. __libc_unwind_link_get must not fail if libgcc_s > + has already been loaded by other means. */ > +static struct unwind_link global; > + > +/* dlopen handle. Also used for the double-checked locking idiom. */ > +static void *global_libgcc_handle; > + > +/* We cannot use __libc_once because the pthread_once implementation > + may depend on unwinding. */ > +__libc_lock_define (static, lock); > + > +struct unwind_link * > +__libc_unwind_link_get (void) > +{ > + /* Double-checked locking idiom. Synchronizes with the release MO > + store at the end of this function. */ > + if (atomic_load_acquire (&global_libgcc_handle) != NULL) > + return &global; > + > + /* Initialize a copy of the data, so that we do not need about > + unlocking in case the dynamic loader somehow triggers > + unwinding. */ > + void *local_libgcc_handle = __libc_dlopen (LIBGCC_S_SO); > + if (local_libgcc_handle == NULL) > + { > + __libc_lock_unlock (lock); > + return NULL; > + } > + > + struct unwind_link local; > + local.ptr__Unwind_Backtrace > + = __libc_dlsym (local_libgcc_handle, "_Unwind_Backtrace"); > + local.ptr__Unwind_ForcedUnwind > + = __libc_dlsym (local_libgcc_handle, "_Unwind_ForcedUnwind"); > + local.ptr__Unwind_GetCFA > + = __libc_dlsym (local_libgcc_handle, "_Unwind_GetCFA"); > +#if UNWIND_LINK_GETIP > + local.ptr__Unwind_GetIP > + = __libc_dlsym (local_libgcc_handle, "_Unwind_GetIP"); > +#endif > + local.ptr__Unwind_Resume > + = __libc_dlsym (local_libgcc_handle, "_Unwind_Resume"); > +#if UNWIND_LINK_FRAME_STATE_FOR > + local.ptr___frame_state_for > + = __libc_dlsym (local_libgcc_handle, "__frame_state_for"); > +#endif > + local.ptr_personality > + = __libc_dlsym (local_libgcc_handle, "__gcc_personality_v0"); > + UNWIND_LINK_EXTRA_INIT > + > + /* If a symbol is missing, libgcc_s has somehow been corrupted. */ > + assert (local.ptr__Unwind_Backtrace != NULL); > + assert (local.ptr__Unwind_ForcedUnwind != NULL); > + assert (local.ptr__Unwind_GetCFA != NULL); > +#if UNWIND_LINK_GETIP > + assert (local.ptr__Unwind_GetIP != NULL); > +#endif > + assert (local.ptr__Unwind_Resume != NULL); > + assert (local.ptr_personality != NULL); > + > +#ifdef PTR_MANGLE > + PTR_MANGLE (local.ptr__Unwind_Backtrace); > + PTR_MANGLE (local.ptr__Unwind_ForcedUnwind); > + PTR_MANGLE (local.ptr__Unwind_GetCFA); > +# if UNWIND_LINK_GETIP > + PTR_MANGLE (local.ptr__Unwind_GetIP); > +# endif > + PTR_MANGLE (local.ptr__Unwind_Resume); > +# if UNWIND_LINK_FRAME_STATE_FOR > + PTR_MANGLE (local.ptr___frame_state_for); > +# endif > + PTR_MANGLE (local.ptr_personality); > +#endif > + > + __libc_lock_lock (lock); > + if (atomic_load_relaxed (&global_libgcc_handle) != NULL) > + /* This thread lost the race. Clean up. */ > + __libc_dlclose (local_libgcc_handle); > + else > + { > + global = local; > + > + /* Completes the double-checked locking idiom. */ > + atomic_store_release (&global_libgcc_handle, local_libgcc_handle); > + } > + > + __libc_lock_unlock (lock); > + return &global; > +} > +libc_hidden_def (__libc_unwind_link_get) > + > +void > +__libc_unwind_link_after_fork (void) > +{ > + if (__libc_lock_trylock (lock) == 0) > + /* The lock was not acquired during the fork. This covers both > + the initialized and uninitialized case. */ > + __libc_lock_unlock (lock); > + else > + { > + /* Initialization was in progress in another thread. > + Reinitialize the lock. */ > + __libc_lock_init (lock); > + global_libgcc_handle = NULL; > + } > +} > + > +void __libc_freeres_fn_section > +__libc_unwind_link_freeres (void) > +{ > + if (global_libgcc_handle != NULL) > + { > + __libc_dlclose (global_libgcc_handle ); > + global_libgcc_handle = NULL; > + } > +} OK. > + > +#endif /* SHARED */ > diff --git a/sysdeps/alpha/unwind-arch.h b/sysdeps/alpha/unwind-arch.h > new file mode 100644 > index 0000000000..9cb37fa604 > --- /dev/null > +++ b/sysdeps/alpha/unwind-arch.h > @@ -0,0 +1,28 @@ > +/* Dynamic loading of the libgcc unwinder. alpha customization. > + 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/>. */ > + > +#ifndef _ARCH_UNWIND_LINK_H > +#define _ARCH_UNWIND_LINK_H > + > +#define UNWIND_LINK_GETIP 1 > +#define UNWIND_LINK_FRAME_STATE_FOR 1 > +#define UNWIND_LINK_FRAME_ADJUSTMENT 0 > +#define UNWIND_LINK_EXTRA_FIELDS > +#define UNWIND_LINK_EXTRA_INIT OK. > + > +#endif /* _ARCH_UNWIND_LINK_H */ > diff --git a/sysdeps/arm/unwind-arch.h b/sysdeps/arm/unwind-arch.h > new file mode 100644 > index 0000000000..fcf889b3c7 > --- /dev/null > +++ b/sysdeps/arm/unwind-arch.h > @@ -0,0 +1,35 @@ > +/* Dynamic loading of the libgcc unwinder. Arm customization. > + 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/>. */ > + > +#ifndef _ARCH_UNWIND_LINK_H > +#define _ARCH_UNWIND_LINK_H > + > +/* On arm, _Unwind_GetIP is a macro. */ > +#define UNWIND_LINK_GETIP 0 > + > +#define UNWIND_LINK_FRAME_STATE_FOR 0 > +#define UNWIND_LINK_FRAME_ADJUSTMENT 0 > +#define UNWIND_LINK_EXTRA_FIELDS \ > + __typeof (_Unwind_VRS_Get) *ptr__Unwind_VRS_Get; > +#define UNWIND_LINK_EXTRA_INIT \ > + local.ptr__Unwind_VRS_Get \ > + = __libc_dlsym (local_libgcc_handle, "_Unwind_VRS_Get"); \ > + assert (local.ptr__Unwind_VRS_Get != NULL); \ > + PTR_MANGLE (local.ptr__Unwind_VRS_Get); > + > +#endif /* _ARCH_UNWIND_LINK_H */ > diff --git a/sysdeps/generic/unwind-arch.h b/sysdeps/generic/unwind-arch.h > index feda585e8d..ead6674279 100644 > --- a/sysdeps/generic/unwind-arch.h > +++ b/sysdeps/generic/unwind-arch.h > @@ -1,5 +1,5 @@ > -/* Return backtrace of current program state. Arch-specific bits. > - Copyright (C) 2020-2021 Free Software Foundation, Inc. > +/* Dynamic loading of the libgcc unwinder. Generic version of parameters. > + 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 > @@ -16,15 +16,20 @@ > License along with the GNU C Library; if not, see > <https://www.gnu.org/licenses/>. */ > > -#ifndef _UNWIND_ARCH_H > -#define _UNWIND_ARCH_H > +#ifndef _ARCH_UNWIND_LINK_H > +#define _ARCH_UNWIND_LINK_H > > -#include <unwind.h> > +/* The _Unwind_GetIP function is supported. */ > +#define UNWIND_LINK_GETIP 1 > > -static inline void * > -unwind_arch_adjustment (void *prev, void *addr) > -{ > - return addr; > -} > +/* The __frame_state_for function is needed and re-exported from glibc. */ > +#define UNWIND_LINK_FRAME_STATE_FOR 0 > > -#endif > +/* No adjustment of the is needed. */ > +#define UNWIND_LINK_FRAME_ADJUSTMENT 0 > + > +/* There are no extra fields in struct unwind_link in the generic version. */ > +#define UNWIND_LINK_EXTRA_FIELDS > +#define UNWIND_LINK_EXTRA_INIT > + > +#endif /* _ARCH_UNWIND_LINK_H */ > diff --git a/sysdeps/generic/unwind-link.h b/sysdeps/generic/unwind-link.h > new file mode 100644 > index 0000000000..3527cebe2d > --- /dev/null > +++ b/sysdeps/generic/unwind-link.h > @@ -0,0 +1,106 @@ > +/* Dynamic loading of the libgcc unwinder. Generic version. > + 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/>. */ > + > +#ifndef _UNWIND_LINK_H > +#define _UNWIND_LINK_H > + > +#include <unwind.h> > +#include <unwind-arch.h> > + > +#if !UNWIND_LINK_FRAME_ADJUSTMENT > +static inline void * > +unwind_arch_adjustment (void *prev, void *addr) > +{ > + return addr; > +} > +#endif > + > +#ifdef SHARED > +# include <sysdep.h> > +# include <unwind-resume.h> > + > +# if UNWIND_LINK_FRAME_STATE_FOR > +struct frame_state; > +# endif > + > +struct unwind_link > +{ > + __typeof (_Unwind_Backtrace) *ptr__Unwind_Backtrace; > + __typeof (_Unwind_ForcedUnwind) *ptr__Unwind_ForcedUnwind; > + __typeof (_Unwind_GetCFA) *ptr__Unwind_GetCFA; > +# if UNWIND_LINK_GETIP > + __typeof (_Unwind_GetIP) *ptr__Unwind_GetIP; > +# endif > + __typeof (_Unwind_Resume) *ptr__Unwind_Resume; > +#if UNWIND_LINK_FRAME_STATE_FOR > + struct frame_state *(*ptr___frame_state_for) (void *, struct frame_state *); > +#endif > + _Unwind_Reason_Code (*ptr_personality) PERSONALITY_PROTO; > + UNWIND_LINK_EXTRA_FIELDS > +}; > + > +/* Return a pointer to the implementation, or NULL on failure. */ > +struct unwind_link *__libc_unwind_link_get (void); > +libc_hidden_proto (__libc_unwind_link_get) > + > +/* UNWIND_LINK_PTR returns the stored function pointer NAME from the > + cached unwind link OBJ (which was previously returned by > + __libc_unwind_link_get). */ > +# ifdef PTR_DEMANGLE > +# define UNWIND_LINK_PTR(obj, name, ...) \ > + ({ \ > + __typeof ((obj)->ptr_##name) __unwind_fptr = (obj)->ptr_##name; \ > + PTR_DEMANGLE (__unwind_fptr); \ > + __unwind_fptr; \ > + }) > +# else /* !PTR_DEMANGLE */ > +# define UNWIND_LINK_PTR(obj, name, ...) ((obj)->ptr_##name) > +# endif > + > +/* Called from fork, in the new subprocess. */ > +void __libc_unwind_link_after_fork (void); > + > +/* Called from __libc_freeres. */ > +void __libc_unwind_link_freeres (void) attribute_hidden; > + > +#else /* !SHARED */ > + > +/* Dummy implementation so that the code can be shared with the SHARED > + version. */ > +struct unwind_link; > +static inline struct unwind_link * > +__libc_unwind_link_get (void) > +{ > + /* Return something that is not a null pointer, so that error checks > + succeed. */ > + return (struct unwind_link *) 1; > +} > + > +/* Directly call the static implementation. */ > +# define UNWIND_LINK_PTR(obj, name, ...) \ > + ((void) (obj), &name) > + > +static inline void > +__libc_unwind_link_after_fork (void) > +{ > + /* No need to clean up if the unwinder is statically linked. */ > +} > + > +#endif /* !SHARED */ > + > +#endif /* _UNWIND_LINK_H */ > diff --git a/sysdeps/i386/unwind-arch.h b/sysdeps/i386/unwind-arch.h > new file mode 100644 > index 0000000000..01c74fe814 > --- /dev/null > +++ b/sysdeps/i386/unwind-arch.h > @@ -0,0 +1,39 @@ > +/* Dynamic loading of the libgcc unwinder. i386 customization. > + 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/>. */ > + > +#ifndef _ARCH_UNWIND_LINK_H > +#define _ARCH_UNWIND_LINK_H > + > +#define UNWIND_LINK_GETIP 1 > +#define UNWIND_LINK_FRAME_STATE_FOR 1 > +#define UNWIND_LINK_FRAME_ADJUSTMENT 0 > +#define UNWIND_LINK_EXTRA_FIELDS \ > + __typeof (_Unwind_GetGR) *ptr__Unwind_GetGR; > +#define UNWIND_LINK_EXTRA_INIT_SHARED \ > + local.ptr__Unwind_GetGR \ > + = __libc_dlsym (local_libgcc_handle, "_Unwind_GetGR"); \ > + assert (local.ptr__Unwind_GetGR != NULL); > +#ifdef PTR_MANGLE > +# define UNWIND_LINK_EXTRA_INIT \ > + UNWIND_LINK_EXTRA_INIT_SHARED \ > + PTR_MANGLE (local.ptr__Unwind_GetGR); > +#else > +# define UNWIND_LINK_EXTRA_INIT UNWIND_LINK_EXTRA_INIT_SHARED > +#endif > + > +#endif /* _ARCH_UNWIND_LINK_H */ > diff --git a/sysdeps/ia64/unwind-arch.h b/sysdeps/ia64/unwind-arch.h > new file mode 100644 > index 0000000000..df294dedbe > --- /dev/null > +++ b/sysdeps/ia64/unwind-arch.h > @@ -0,0 +1,32 @@ > +/* Dynamic loading of the libgcc unwinder. ia64 customization. > + 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/>. */ > + > +#ifndef _ARCH_UNWIND_LINK_H > + > +#define UNWIND_LINK_GETIP 1 > +#define UNWIND_LINK_FRAME_STATE_FOR 1 > +#define UNWIND_LINK_FRAME_ADJUSTMENT 0 > +#define UNWIND_LINK_EXTRA_FIELDS \ > + __typeof (_Unwind_GetBSP) *ptr__Unwind_GetBSP; > +#define UNWIND_LINK_EXTRA_INIT \ > + local.ptr__Unwind_GetBSP \ > + = __libc_dlsym (local_libgcc_handle, "_Unwind_GetBSP"); \ > + assert (local.ptr__Unwind_GetBSP != NULL); \ > + PTR_MANGLE (local.ptr__Unwind_GetBSP); > + > +#endif /* _ARCH_UNWIND_LINK_H */ > diff --git a/sysdeps/m68k/m680x0/unwind-arch.h b/sysdeps/m68k/m680x0/unwind-arch.h > new file mode 100644 > index 0000000000..fea71d45ce > --- /dev/null > +++ b/sysdeps/m68k/m680x0/unwind-arch.h > @@ -0,0 +1,26 @@ > +/* Dynamic loading of the libgcc unwinder. Baseline m68k customization. > + 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/>. */ > + > +#ifndef _ARCH_UNWIND_LINK_H > + > +#include <sysdeps/m68k/unwind-arch.h> > + > +#undef UNWIND_LINK_FRAME_STATE_FOR > +#define UNWIND_LINK_FRAME_STATE_FOR 1 > + > +#endif /* _ARCH_UNWIND_LINK_H */ > diff --git a/sysdeps/m68k/unwind-arch.h b/sysdeps/m68k/unwind-arch.h > new file mode 100644 > index 0000000000..37f1013c7e > --- /dev/null > +++ b/sysdeps/m68k/unwind-arch.h > @@ -0,0 +1,35 @@ > +/* Dynamic loading of the libgcc unwinder. m68k customization. > + 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/>. */ > + > +#ifndef _ARCH_UNWIND_LINK_H > +#define _ARCH_UNWIND_LINK_H > + > +#define UNWIND_LINK_GETIP 1 > +#define UNWIND_LINK_FRAME_ADJUSTMENT 0 > +#define UNWIND_LINK_EXTRA_FIELDS \ > + __typeof (_Unwind_GetGR) *ptr__Unwind_GetGR; > +#define UNWIND_LINK_EXTRA_INIT \ > + local.ptr__Unwind_GetGR \ > + = __libc_dlsym (local_libgcc_handle, "_Unwind_GetGR"); \ > + assert (local.ptr__Unwind_GetGR != NULL); \ > + PTR_MANGLE (local.ptr__Unwind_GetGR); > + > +/* This is overriden by the m680x0 variant. */ > +#define UNWIND_LINK_FRAME_STATE_FOR 0 > + > +#endif /* _ARCH_UNWIND_LINK_H */ > diff --git a/sysdeps/mach/hurd/fork.c b/sysdeps/mach/hurd/fork.c > index fb6c7ee8b7..2b39f4e8b5 100644 > --- a/sysdeps/mach/hurd/fork.c > +++ b/sysdeps/mach/hurd/fork.c > @@ -29,6 +29,7 @@ > #include <tls.h> > #include <malloc/malloc-internal.h> > #include <nss/nss_database.h> > +#include <unwind-link.h> > > #undef __fork > > @@ -667,6 +668,8 @@ __fork (void) > __sigemptyset (&_hurd_global_sigstate->pending); > __sigemptyset (&ss->pending); > > + __libc_unwind_link_after_fork (); > + > /* Release malloc locks. */ > _hurd_malloc_fork_child (); > call_function_static_weak (__malloc_fork_unlock_child); > diff --git a/sysdeps/unix/sysv/linux/mips/unwind-arch.h b/sysdeps/mips/unwind-arch.h > similarity index 85% > rename from sysdeps/unix/sysv/linux/mips/unwind-arch.h > rename to sysdeps/mips/unwind-arch.h > index 38bc60cde6..78de42e001 100644 > --- a/sysdeps/unix/sysv/linux/mips/unwind-arch.h > +++ b/sysdeps/mips/unwind-arch.h > @@ -1,4 +1,4 @@ > -/* Return backtrace of current program state. Arch-specific bits. > +/* Dynamic loading of the libgcc unwinder. MIPS customization. > Copyright (C) 2020-2021 Free Software Foundation, Inc. > This file is part of the GNU C Library. > > @@ -16,10 +16,17 @@ > License along with the GNU C Library; if not, see > <https://www.gnu.org/licenses/>. */ > > -#ifndef _UNWIND_ARCH_H > -#define _UNWIND_ARCH_H > +#ifndef _ARCH_UNWIND_LINK_H > +#define _ARCH_UNWIND_LINK_H > > #include <stdint.h> > +#include <sys/syscall.h> > + > +#define UNWIND_LINK_GETIP 1 > +#define UNWIND_LINK_FRAME_STATE_FOR 1 > +#define UNWIND_LINK_FRAME_ADJUSTMENT 1 > +#define UNWIND_LINK_EXTRA_FIELDS > +#define UNWIND_LINK_EXTRA_INIT > > /* MIPS fallback code handle a frame where its FDE can not be obtained > (for instance a signal frame) by reading the kernel allocated signal frame > @@ -49,7 +56,7 @@ unwind_arch_adjustment (void *prev, void *addr) > > 24021061 li v0, 0x1061 (rt_sigreturn) > 0000000c syscall > - or > + or > 24021017 li v0, 0x1017 (sigreturn) > 0000000c syscall */ > if (pc[1] != 0x0000000c) > @@ -64,4 +71,4 @@ unwind_arch_adjustment (void *prev, void *addr) > return addr; > } > > -#endif > +#endif /* _ARCH_UNWIND_LINK_H */ > diff --git a/sysdeps/nptl/fork.c b/sysdeps/nptl/fork.c > index 26703d958f..4fb4c2d254 100644 > --- a/sysdeps/nptl/fork.c > +++ b/sysdeps/nptl/fork.c > @@ -33,6 +33,7 @@ > #include <futex-internal.h> > #include <malloc/malloc-internal.h> > #include <nss/nss_database.h> > +#include <unwind-link.h> > > static void > fresetlockfiles (void) > @@ -116,6 +117,8 @@ __libc_fork (void) > /* Reset the lock state in the multi-threaded case. */ > if (multiple_threads) > { > + __libc_unwind_link_after_fork (); > + > /* Release malloc locks. */ > call_function_static_weak (__malloc_fork_unlock_child); > > diff --git a/sysdeps/powerpc/powerpc32/unwind-arch.h b/sysdeps/powerpc/powerpc32/unwind-arch.h > new file mode 100644 > index 0000000000..f2869ac3ae > --- /dev/null > +++ b/sysdeps/powerpc/powerpc32/unwind-arch.h > @@ -0,0 +1,28 @@ > +/* Dynamic loading of the libgcc unwinder. powerpc customization. > + 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/>. */ > + > +#ifndef _ARCH_UNWIND_LINK_H > +#define _ARCH_UNWIND_LINK_H > + > +#define UNWIND_LINK_GETIP 1 > +#define UNWIND_LINK_FRAME_STATE_FOR 1 > +#define UNWIND_LINK_FRAME_ADJUSTMENT 0 > +#define UNWIND_LINK_EXTRA_FIELDS > +#define UNWIND_LINK_EXTRA_INIT > + > +#endif /* _ARCH_UNWIND_LINK_H */ > diff --git a/sysdeps/s390/unwind-arch.h b/sysdeps/s390/unwind-arch.h > new file mode 100644 > index 0000000000..64d976de03 > --- /dev/null > +++ b/sysdeps/s390/unwind-arch.h > @@ -0,0 +1,28 @@ > +/* Dynamic loading of the libgcc unwinder. S/390 customization. > + 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/>. */ > + > +#ifndef _ARCH_UNWIND_LINK_H > +#define _ARCH_UNWIND_LINK_H > + > +#define UNWIND_LINK_GETIP 1 > +#define UNWIND_LINK_FRAME_STATE_FOR 1 > +#define UNWIND_LINK_FRAME_ADJUSTMENT 0 > +#define UNWIND_LINK_EXTRA_FIELDS > +#define UNWIND_LINK_EXTRA_INIT > + > +#endif /* _ARCH_UNWIND_LINK_H */ > diff --git a/sysdeps/sh/unwind-arch.h b/sysdeps/sh/unwind-arch.h > new file mode 100644 > index 0000000000..8fdac6322b > --- /dev/null > +++ b/sysdeps/sh/unwind-arch.h > @@ -0,0 +1,28 @@ > +/* Dynamic loading of the libgcc unwinder. SH customization. > + 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/>. */ > + > +#ifndef _ARCH_UNWIND_LINK_H > +#define _ARCH_UNWIND_LINK_H > + > +#define UNWIND_LINK_GETIP 1 > +#define UNWIND_LINK_FRAME_STATE_FOR 1 > +#define UNWIND_LINK_FRAME_ADJUSTMENT 0 > +#define UNWIND_LINK_EXTRA_FIELDS > +#define UNWIND_LINK_EXTRA_INIT > + > +#endif /* _ARCH_UNWIND_LINK_H */ > diff --git a/sysdeps/sparc/unwind-arch.h b/sysdeps/sparc/unwind-arch.h > new file mode 100644 > index 0000000000..299fa006be > --- /dev/null > +++ b/sysdeps/sparc/unwind-arch.h > @@ -0,0 +1,28 @@ > +/* Dynamic loading of the libgcc unwinder. SPARC customization. > + 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/>. */ > + > +#ifndef _ARCH_UNWIND_LINK_H > +#define _ARCH_UNWIND_LINK_H > + > +#define UNWIND_LINK_GETIP 1 > +#define UNWIND_LINK_FRAME_STATE_FOR 1 > +#define UNWIND_LINK_FRAME_ADJUSTMENT 0 > +#define UNWIND_LINK_EXTRA_FIELDS > +#define UNWIND_LINK_EXTRA_INIT > + > +#endif /* _ARCH_UNWIND_LINK_H */ >
diff --git a/debug/backtrace.c b/debug/backtrace.c index 9449c51f06..5ded57bfc4 100644 --- a/debug/backtrace.c +++ b/debug/backtrace.c @@ -23,7 +23,7 @@ #include <gnu/lib-names.h> #include <stdlib.h> #include <unwind.h> -#include <unwind-arch.h> +#include <unwind-link.h> struct trace_arg { diff --git a/malloc/set-freeres.c b/malloc/set-freeres.c index 24c7194aa8..817fbea8b8 100644 --- a/malloc/set-freeres.c +++ b/malloc/set-freeres.c @@ -19,6 +19,7 @@ #include <stdlib.h> #include <set-hooks.h> #include <libc-internal.h> +#include <unwind-link.h> #include "../nss/nsswitch.h" #include "../libio/libioP.h" @@ -61,6 +62,10 @@ __libc_freeres (void) if (&__libpthread_freeres != NULL) __libpthread_freeres (); +#ifdef SHARED + __libc_unwind_link_freeres (); +#endif + for (p = symbol_set_first_element (__libc_freeres_ptrs); !symbol_set_end_p (__libc_freeres_ptrs, p); ++p) free (*p); diff --git a/misc/Makefile b/misc/Makefile index b08d7c68ab..cfc15355d6 100644 --- a/misc/Makefile +++ b/misc/Makefile @@ -73,7 +73,7 @@ routines := brk sbrk sstk ioctl \ fgetxattr flistxattr fremovexattr fsetxattr getxattr \ listxattr lgetxattr llistxattr lremovexattr lsetxattr \ removexattr setxattr getauxval ifunc-impl-list makedev \ - allocate_once fd_to_filename single_threaded + allocate_once fd_to_filename single_threaded unwind-link generated += tst-error1.mtrace tst-error1-mem.out \ tst-allocate_once.mtrace tst-allocate_once-mem.out diff --git a/misc/Versions b/misc/Versions index 95666f6548..d5b348e83a 100644 --- a/misc/Versions +++ b/misc/Versions @@ -172,5 +172,6 @@ libc { __mmap; __munmap; __mprotect; __sched_get_priority_min; __sched_get_priority_max; __libc_allocate_once_slow; + __libc_unwind_link_get; } } diff --git a/misc/unwind-link.c b/misc/unwind-link.c new file mode 100644 index 0000000000..ad3d02bf32 --- /dev/null +++ b/misc/unwind-link.c @@ -0,0 +1,145 @@ +/* Dynamic loading of the libgcc unwinder. + 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/>. */ + +#ifdef SHARED + +#include <assert.h> +#include <dlfcn.h> +#include <gnu/lib-names.h> +#include <unwind-link.h> +#include <libc-lock.h> + +/* Statically allocate the object, so that we do not have to deal with + malloc failure. __libc_unwind_link_get must not fail if libgcc_s + has already been loaded by other means. */ +static struct unwind_link global; + +/* dlopen handle. Also used for the double-checked locking idiom. */ +static void *global_libgcc_handle; + +/* We cannot use __libc_once because the pthread_once implementation + may depend on unwinding. */ +__libc_lock_define (static, lock); + +struct unwind_link * +__libc_unwind_link_get (void) +{ + /* Double-checked locking idiom. Synchronizes with the release MO + store at the end of this function. */ + if (atomic_load_acquire (&global_libgcc_handle) != NULL) + return &global; + + /* Initialize a copy of the data, so that we do not need about + unlocking in case the dynamic loader somehow triggers + unwinding. */ + void *local_libgcc_handle = __libc_dlopen (LIBGCC_S_SO); + if (local_libgcc_handle == NULL) + { + __libc_lock_unlock (lock); + return NULL; + } + + struct unwind_link local; + local.ptr__Unwind_Backtrace + = __libc_dlsym (local_libgcc_handle, "_Unwind_Backtrace"); + local.ptr__Unwind_ForcedUnwind + = __libc_dlsym (local_libgcc_handle, "_Unwind_ForcedUnwind"); + local.ptr__Unwind_GetCFA + = __libc_dlsym (local_libgcc_handle, "_Unwind_GetCFA"); +#if UNWIND_LINK_GETIP + local.ptr__Unwind_GetIP + = __libc_dlsym (local_libgcc_handle, "_Unwind_GetIP"); +#endif + local.ptr__Unwind_Resume + = __libc_dlsym (local_libgcc_handle, "_Unwind_Resume"); +#if UNWIND_LINK_FRAME_STATE_FOR + local.ptr___frame_state_for + = __libc_dlsym (local_libgcc_handle, "__frame_state_for"); +#endif + local.ptr_personality + = __libc_dlsym (local_libgcc_handle, "__gcc_personality_v0"); + UNWIND_LINK_EXTRA_INIT + + /* If a symbol is missing, libgcc_s has somehow been corrupted. */ + assert (local.ptr__Unwind_Backtrace != NULL); + assert (local.ptr__Unwind_ForcedUnwind != NULL); + assert (local.ptr__Unwind_GetCFA != NULL); +#if UNWIND_LINK_GETIP + assert (local.ptr__Unwind_GetIP != NULL); +#endif + assert (local.ptr__Unwind_Resume != NULL); + assert (local.ptr_personality != NULL); + +#ifdef PTR_MANGLE + PTR_MANGLE (local.ptr__Unwind_Backtrace); + PTR_MANGLE (local.ptr__Unwind_ForcedUnwind); + PTR_MANGLE (local.ptr__Unwind_GetCFA); +# if UNWIND_LINK_GETIP + PTR_MANGLE (local.ptr__Unwind_GetIP); +# endif + PTR_MANGLE (local.ptr__Unwind_Resume); +# if UNWIND_LINK_FRAME_STATE_FOR + PTR_MANGLE (local.ptr___frame_state_for); +# endif + PTR_MANGLE (local.ptr_personality); +#endif + + __libc_lock_lock (lock); + if (atomic_load_relaxed (&global_libgcc_handle) != NULL) + /* This thread lost the race. Clean up. */ + __libc_dlclose (local_libgcc_handle); + else + { + global = local; + + /* Completes the double-checked locking idiom. */ + atomic_store_release (&global_libgcc_handle, local_libgcc_handle); + } + + __libc_lock_unlock (lock); + return &global; +} +libc_hidden_def (__libc_unwind_link_get) + +void +__libc_unwind_link_after_fork (void) +{ + if (__libc_lock_trylock (lock) == 0) + /* The lock was not acquired during the fork. This covers both + the initialized and uninitialized case. */ + __libc_lock_unlock (lock); + else + { + /* Initialization was in progress in another thread. + Reinitialize the lock. */ + __libc_lock_init (lock); + global_libgcc_handle = NULL; + } +} + +void __libc_freeres_fn_section +__libc_unwind_link_freeres (void) +{ + if (global_libgcc_handle != NULL) + { + __libc_dlclose (global_libgcc_handle ); + global_libgcc_handle = NULL; + } +} + +#endif /* SHARED */ diff --git a/sysdeps/alpha/unwind-arch.h b/sysdeps/alpha/unwind-arch.h new file mode 100644 index 0000000000..9cb37fa604 --- /dev/null +++ b/sysdeps/alpha/unwind-arch.h @@ -0,0 +1,28 @@ +/* Dynamic loading of the libgcc unwinder. alpha customization. + 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/>. */ + +#ifndef _ARCH_UNWIND_LINK_H +#define _ARCH_UNWIND_LINK_H + +#define UNWIND_LINK_GETIP 1 +#define UNWIND_LINK_FRAME_STATE_FOR 1 +#define UNWIND_LINK_FRAME_ADJUSTMENT 0 +#define UNWIND_LINK_EXTRA_FIELDS +#define UNWIND_LINK_EXTRA_INIT + +#endif /* _ARCH_UNWIND_LINK_H */ diff --git a/sysdeps/arm/unwind-arch.h b/sysdeps/arm/unwind-arch.h new file mode 100644 index 0000000000..fcf889b3c7 --- /dev/null +++ b/sysdeps/arm/unwind-arch.h @@ -0,0 +1,35 @@ +/* Dynamic loading of the libgcc unwinder. Arm customization. + 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/>. */ + +#ifndef _ARCH_UNWIND_LINK_H +#define _ARCH_UNWIND_LINK_H + +/* On arm, _Unwind_GetIP is a macro. */ +#define UNWIND_LINK_GETIP 0 + +#define UNWIND_LINK_FRAME_STATE_FOR 0 +#define UNWIND_LINK_FRAME_ADJUSTMENT 0 +#define UNWIND_LINK_EXTRA_FIELDS \ + __typeof (_Unwind_VRS_Get) *ptr__Unwind_VRS_Get; +#define UNWIND_LINK_EXTRA_INIT \ + local.ptr__Unwind_VRS_Get \ + = __libc_dlsym (local_libgcc_handle, "_Unwind_VRS_Get"); \ + assert (local.ptr__Unwind_VRS_Get != NULL); \ + PTR_MANGLE (local.ptr__Unwind_VRS_Get); + +#endif /* _ARCH_UNWIND_LINK_H */ diff --git a/sysdeps/generic/unwind-arch.h b/sysdeps/generic/unwind-arch.h index feda585e8d..ead6674279 100644 --- a/sysdeps/generic/unwind-arch.h +++ b/sysdeps/generic/unwind-arch.h @@ -1,5 +1,5 @@ -/* Return backtrace of current program state. Arch-specific bits. - Copyright (C) 2020-2021 Free Software Foundation, Inc. +/* Dynamic loading of the libgcc unwinder. Generic version of parameters. + 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 @@ -16,15 +16,20 @@ License along with the GNU C Library; if not, see <https://www.gnu.org/licenses/>. */ -#ifndef _UNWIND_ARCH_H -#define _UNWIND_ARCH_H +#ifndef _ARCH_UNWIND_LINK_H +#define _ARCH_UNWIND_LINK_H -#include <unwind.h> +/* The _Unwind_GetIP function is supported. */ +#define UNWIND_LINK_GETIP 1 -static inline void * -unwind_arch_adjustment (void *prev, void *addr) -{ - return addr; -} +/* The __frame_state_for function is needed and re-exported from glibc. */ +#define UNWIND_LINK_FRAME_STATE_FOR 0 -#endif +/* No adjustment of the is needed. */ +#define UNWIND_LINK_FRAME_ADJUSTMENT 0 + +/* There are no extra fields in struct unwind_link in the generic version. */ +#define UNWIND_LINK_EXTRA_FIELDS +#define UNWIND_LINK_EXTRA_INIT + +#endif /* _ARCH_UNWIND_LINK_H */ diff --git a/sysdeps/generic/unwind-link.h b/sysdeps/generic/unwind-link.h new file mode 100644 index 0000000000..3527cebe2d --- /dev/null +++ b/sysdeps/generic/unwind-link.h @@ -0,0 +1,106 @@ +/* Dynamic loading of the libgcc unwinder. Generic version. + 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/>. */ + +#ifndef _UNWIND_LINK_H +#define _UNWIND_LINK_H + +#include <unwind.h> +#include <unwind-arch.h> + +#if !UNWIND_LINK_FRAME_ADJUSTMENT +static inline void * +unwind_arch_adjustment (void *prev, void *addr) +{ + return addr; +} +#endif + +#ifdef SHARED +# include <sysdep.h> +# include <unwind-resume.h> + +# if UNWIND_LINK_FRAME_STATE_FOR +struct frame_state; +# endif + +struct unwind_link +{ + __typeof (_Unwind_Backtrace) *ptr__Unwind_Backtrace; + __typeof (_Unwind_ForcedUnwind) *ptr__Unwind_ForcedUnwind; + __typeof (_Unwind_GetCFA) *ptr__Unwind_GetCFA; +# if UNWIND_LINK_GETIP + __typeof (_Unwind_GetIP) *ptr__Unwind_GetIP; +# endif + __typeof (_Unwind_Resume) *ptr__Unwind_Resume; +#if UNWIND_LINK_FRAME_STATE_FOR + struct frame_state *(*ptr___frame_state_for) (void *, struct frame_state *); +#endif + _Unwind_Reason_Code (*ptr_personality) PERSONALITY_PROTO; + UNWIND_LINK_EXTRA_FIELDS +}; + +/* Return a pointer to the implementation, or NULL on failure. */ +struct unwind_link *__libc_unwind_link_get (void); +libc_hidden_proto (__libc_unwind_link_get) + +/* UNWIND_LINK_PTR returns the stored function pointer NAME from the + cached unwind link OBJ (which was previously returned by + __libc_unwind_link_get). */ +# ifdef PTR_DEMANGLE +# define UNWIND_LINK_PTR(obj, name, ...) \ + ({ \ + __typeof ((obj)->ptr_##name) __unwind_fptr = (obj)->ptr_##name; \ + PTR_DEMANGLE (__unwind_fptr); \ + __unwind_fptr; \ + }) +# else /* !PTR_DEMANGLE */ +# define UNWIND_LINK_PTR(obj, name, ...) ((obj)->ptr_##name) +# endif + +/* Called from fork, in the new subprocess. */ +void __libc_unwind_link_after_fork (void); + +/* Called from __libc_freeres. */ +void __libc_unwind_link_freeres (void) attribute_hidden; + +#else /* !SHARED */ + +/* Dummy implementation so that the code can be shared with the SHARED + version. */ +struct unwind_link; +static inline struct unwind_link * +__libc_unwind_link_get (void) +{ + /* Return something that is not a null pointer, so that error checks + succeed. */ + return (struct unwind_link *) 1; +} + +/* Directly call the static implementation. */ +# define UNWIND_LINK_PTR(obj, name, ...) \ + ((void) (obj), &name) + +static inline void +__libc_unwind_link_after_fork (void) +{ + /* No need to clean up if the unwinder is statically linked. */ +} + +#endif /* !SHARED */ + +#endif /* _UNWIND_LINK_H */ diff --git a/sysdeps/i386/unwind-arch.h b/sysdeps/i386/unwind-arch.h new file mode 100644 index 0000000000..01c74fe814 --- /dev/null +++ b/sysdeps/i386/unwind-arch.h @@ -0,0 +1,39 @@ +/* Dynamic loading of the libgcc unwinder. i386 customization. + 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/>. */ + +#ifndef _ARCH_UNWIND_LINK_H +#define _ARCH_UNWIND_LINK_H + +#define UNWIND_LINK_GETIP 1 +#define UNWIND_LINK_FRAME_STATE_FOR 1 +#define UNWIND_LINK_FRAME_ADJUSTMENT 0 +#define UNWIND_LINK_EXTRA_FIELDS \ + __typeof (_Unwind_GetGR) *ptr__Unwind_GetGR; +#define UNWIND_LINK_EXTRA_INIT_SHARED \ + local.ptr__Unwind_GetGR \ + = __libc_dlsym (local_libgcc_handle, "_Unwind_GetGR"); \ + assert (local.ptr__Unwind_GetGR != NULL); +#ifdef PTR_MANGLE +# define UNWIND_LINK_EXTRA_INIT \ + UNWIND_LINK_EXTRA_INIT_SHARED \ + PTR_MANGLE (local.ptr__Unwind_GetGR); +#else +# define UNWIND_LINK_EXTRA_INIT UNWIND_LINK_EXTRA_INIT_SHARED +#endif + +#endif /* _ARCH_UNWIND_LINK_H */ diff --git a/sysdeps/ia64/unwind-arch.h b/sysdeps/ia64/unwind-arch.h new file mode 100644 index 0000000000..df294dedbe --- /dev/null +++ b/sysdeps/ia64/unwind-arch.h @@ -0,0 +1,32 @@ +/* Dynamic loading of the libgcc unwinder. ia64 customization. + 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/>. */ + +#ifndef _ARCH_UNWIND_LINK_H + +#define UNWIND_LINK_GETIP 1 +#define UNWIND_LINK_FRAME_STATE_FOR 1 +#define UNWIND_LINK_FRAME_ADJUSTMENT 0 +#define UNWIND_LINK_EXTRA_FIELDS \ + __typeof (_Unwind_GetBSP) *ptr__Unwind_GetBSP; +#define UNWIND_LINK_EXTRA_INIT \ + local.ptr__Unwind_GetBSP \ + = __libc_dlsym (local_libgcc_handle, "_Unwind_GetBSP"); \ + assert (local.ptr__Unwind_GetBSP != NULL); \ + PTR_MANGLE (local.ptr__Unwind_GetBSP); + +#endif /* _ARCH_UNWIND_LINK_H */ diff --git a/sysdeps/m68k/m680x0/unwind-arch.h b/sysdeps/m68k/m680x0/unwind-arch.h new file mode 100644 index 0000000000..fea71d45ce --- /dev/null +++ b/sysdeps/m68k/m680x0/unwind-arch.h @@ -0,0 +1,26 @@ +/* Dynamic loading of the libgcc unwinder. Baseline m68k customization. + 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/>. */ + +#ifndef _ARCH_UNWIND_LINK_H + +#include <sysdeps/m68k/unwind-arch.h> + +#undef UNWIND_LINK_FRAME_STATE_FOR +#define UNWIND_LINK_FRAME_STATE_FOR 1 + +#endif /* _ARCH_UNWIND_LINK_H */ diff --git a/sysdeps/m68k/unwind-arch.h b/sysdeps/m68k/unwind-arch.h new file mode 100644 index 0000000000..37f1013c7e --- /dev/null +++ b/sysdeps/m68k/unwind-arch.h @@ -0,0 +1,35 @@ +/* Dynamic loading of the libgcc unwinder. m68k customization. + 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/>. */ + +#ifndef _ARCH_UNWIND_LINK_H +#define _ARCH_UNWIND_LINK_H + +#define UNWIND_LINK_GETIP 1 +#define UNWIND_LINK_FRAME_ADJUSTMENT 0 +#define UNWIND_LINK_EXTRA_FIELDS \ + __typeof (_Unwind_GetGR) *ptr__Unwind_GetGR; +#define UNWIND_LINK_EXTRA_INIT \ + local.ptr__Unwind_GetGR \ + = __libc_dlsym (local_libgcc_handle, "_Unwind_GetGR"); \ + assert (local.ptr__Unwind_GetGR != NULL); \ + PTR_MANGLE (local.ptr__Unwind_GetGR); + +/* This is overriden by the m680x0 variant. */ +#define UNWIND_LINK_FRAME_STATE_FOR 0 + +#endif /* _ARCH_UNWIND_LINK_H */ diff --git a/sysdeps/mach/hurd/fork.c b/sysdeps/mach/hurd/fork.c index fb6c7ee8b7..2b39f4e8b5 100644 --- a/sysdeps/mach/hurd/fork.c +++ b/sysdeps/mach/hurd/fork.c @@ -29,6 +29,7 @@ #include <tls.h> #include <malloc/malloc-internal.h> #include <nss/nss_database.h> +#include <unwind-link.h> #undef __fork @@ -667,6 +668,8 @@ __fork (void) __sigemptyset (&_hurd_global_sigstate->pending); __sigemptyset (&ss->pending); + __libc_unwind_link_after_fork (); + /* Release malloc locks. */ _hurd_malloc_fork_child (); call_function_static_weak (__malloc_fork_unlock_child); diff --git a/sysdeps/unix/sysv/linux/mips/unwind-arch.h b/sysdeps/mips/unwind-arch.h similarity index 85% rename from sysdeps/unix/sysv/linux/mips/unwind-arch.h rename to sysdeps/mips/unwind-arch.h index 38bc60cde6..78de42e001 100644 --- a/sysdeps/unix/sysv/linux/mips/unwind-arch.h +++ b/sysdeps/mips/unwind-arch.h @@ -1,4 +1,4 @@ -/* Return backtrace of current program state. Arch-specific bits. +/* Dynamic loading of the libgcc unwinder. MIPS customization. Copyright (C) 2020-2021 Free Software Foundation, Inc. This file is part of the GNU C Library. @@ -16,10 +16,17 @@ License along with the GNU C Library; if not, see <https://www.gnu.org/licenses/>. */ -#ifndef _UNWIND_ARCH_H -#define _UNWIND_ARCH_H +#ifndef _ARCH_UNWIND_LINK_H +#define _ARCH_UNWIND_LINK_H #include <stdint.h> +#include <sys/syscall.h> + +#define UNWIND_LINK_GETIP 1 +#define UNWIND_LINK_FRAME_STATE_FOR 1 +#define UNWIND_LINK_FRAME_ADJUSTMENT 1 +#define UNWIND_LINK_EXTRA_FIELDS +#define UNWIND_LINK_EXTRA_INIT /* MIPS fallback code handle a frame where its FDE can not be obtained (for instance a signal frame) by reading the kernel allocated signal frame @@ -49,7 +56,7 @@ unwind_arch_adjustment (void *prev, void *addr) 24021061 li v0, 0x1061 (rt_sigreturn) 0000000c syscall - or + or 24021017 li v0, 0x1017 (sigreturn) 0000000c syscall */ if (pc[1] != 0x0000000c) @@ -64,4 +71,4 @@ unwind_arch_adjustment (void *prev, void *addr) return addr; } -#endif +#endif /* _ARCH_UNWIND_LINK_H */ diff --git a/sysdeps/nptl/fork.c b/sysdeps/nptl/fork.c index 26703d958f..4fb4c2d254 100644 --- a/sysdeps/nptl/fork.c +++ b/sysdeps/nptl/fork.c @@ -33,6 +33,7 @@ #include <futex-internal.h> #include <malloc/malloc-internal.h> #include <nss/nss_database.h> +#include <unwind-link.h> static void fresetlockfiles (void) @@ -116,6 +117,8 @@ __libc_fork (void) /* Reset the lock state in the multi-threaded case. */ if (multiple_threads) { + __libc_unwind_link_after_fork (); + /* Release malloc locks. */ call_function_static_weak (__malloc_fork_unlock_child); diff --git a/sysdeps/powerpc/powerpc32/unwind-arch.h b/sysdeps/powerpc/powerpc32/unwind-arch.h new file mode 100644 index 0000000000..f2869ac3ae --- /dev/null +++ b/sysdeps/powerpc/powerpc32/unwind-arch.h @@ -0,0 +1,28 @@ +/* Dynamic loading of the libgcc unwinder. powerpc customization. + 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/>. */ + +#ifndef _ARCH_UNWIND_LINK_H +#define _ARCH_UNWIND_LINK_H + +#define UNWIND_LINK_GETIP 1 +#define UNWIND_LINK_FRAME_STATE_FOR 1 +#define UNWIND_LINK_FRAME_ADJUSTMENT 0 +#define UNWIND_LINK_EXTRA_FIELDS +#define UNWIND_LINK_EXTRA_INIT + +#endif /* _ARCH_UNWIND_LINK_H */ diff --git a/sysdeps/s390/unwind-arch.h b/sysdeps/s390/unwind-arch.h new file mode 100644 index 0000000000..64d976de03 --- /dev/null +++ b/sysdeps/s390/unwind-arch.h @@ -0,0 +1,28 @@ +/* Dynamic loading of the libgcc unwinder. S/390 customization. + 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/>. */ + +#ifndef _ARCH_UNWIND_LINK_H +#define _ARCH_UNWIND_LINK_H + +#define UNWIND_LINK_GETIP 1 +#define UNWIND_LINK_FRAME_STATE_FOR 1 +#define UNWIND_LINK_FRAME_ADJUSTMENT 0 +#define UNWIND_LINK_EXTRA_FIELDS +#define UNWIND_LINK_EXTRA_INIT + +#endif /* _ARCH_UNWIND_LINK_H */ diff --git a/sysdeps/sh/unwind-arch.h b/sysdeps/sh/unwind-arch.h new file mode 100644 index 0000000000..8fdac6322b --- /dev/null +++ b/sysdeps/sh/unwind-arch.h @@ -0,0 +1,28 @@ +/* Dynamic loading of the libgcc unwinder. SH customization. + 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/>. */ + +#ifndef _ARCH_UNWIND_LINK_H +#define _ARCH_UNWIND_LINK_H + +#define UNWIND_LINK_GETIP 1 +#define UNWIND_LINK_FRAME_STATE_FOR 1 +#define UNWIND_LINK_FRAME_ADJUSTMENT 0 +#define UNWIND_LINK_EXTRA_FIELDS +#define UNWIND_LINK_EXTRA_INIT + +#endif /* _ARCH_UNWIND_LINK_H */ diff --git a/sysdeps/sparc/unwind-arch.h b/sysdeps/sparc/unwind-arch.h new file mode 100644 index 0000000000..299fa006be --- /dev/null +++ b/sysdeps/sparc/unwind-arch.h @@ -0,0 +1,28 @@ +/* Dynamic loading of the libgcc unwinder. SPARC customization. + 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/>. */ + +#ifndef _ARCH_UNWIND_LINK_H +#define _ARCH_UNWIND_LINK_H + +#define UNWIND_LINK_GETIP 1 +#define UNWIND_LINK_FRAME_STATE_FOR 1 +#define UNWIND_LINK_FRAME_ADJUSTMENT 0 +#define UNWIND_LINK_EXTRA_FIELDS +#define UNWIND_LINK_EXTRA_INIT + +#endif /* _ARCH_UNWIND_LINK_H */