diff options
| -rw-r--r-- | ChangeLog | 17 | ||||
| -rw-r--r-- | debug/Makefile | 4 | ||||
| -rw-r--r-- | debug/tst-backtrace5.c | 11 | ||||
| -rw-r--r-- | debug/tst-backtrace6.c | 21 | ||||
| -rw-r--r-- | sysdeps/powerpc/powerpc32/backtrace.c | 66 | ||||
| -rw-r--r-- | sysdeps/powerpc/powerpc64/backtrace.c | 36 | ||||
| -rw-r--r-- | sysdeps/unix/sysv/linux/powerpc/bits/libc-vdso.h | 7 | ||||
| -rw-r--r-- | sysdeps/unix/sysv/linux/powerpc/init-first.c | 16 |
8 files changed, 172 insertions, 6 deletions
diff --git a/ChangeLog b/ChangeLog index 577304273e..5340c40333 100644 --- a/ChangeLog +++ b/ChangeLog @@ -1,3 +1,20 @@ +2013-07-23 Adhemerval Zanella <azanella@linux.vnet.ibm.com> + + [BZ #15867] + * sysdeps/powerpc/powerpc32/backtrace.c (__backtrace): Handle signal + trampoline stack frame information. + * sysdeps/powerpc/powerpc64/backtrace.c (__backtrace): Likewise. + * sysdeps/unix/sysv/linux/powerpc/bits/libc-vdso.h + (__vdso_sigtramp_rt64): New variable: PPC64 signal trampoline. + (__vdso_sigtramp32): New variable: PPC32 signal trampoline. + (__vdso_sigtramp_rt32): New variable: PPC32 signal trampoline. + * sysdeps/unix/sysv/linux/powerpc/init-first.c + (_libc_vdso_platform_setup): Initialize the signal trampolines. + * debug/tst-backtrace5.c (fn): Add an option set modify sigaction + sa_flags value. + * debug/tst-backtrace6.c: New file: check backtrace for signal frames, + interrupting a syscall and set with option SA_SIGINFO. + 2013-08-20 Joseph Myers <joseph@codesourcery.com> [BZ #15531] diff --git a/debug/Makefile b/debug/Makefile index 779741f9ef..13ee5c80b8 100644 --- a/debug/Makefile +++ b/debug/Makefile @@ -130,16 +130,18 @@ CFLAGS-tst-backtrace2.c += -funwind-tables CFLAGS-tst-backtrace3.c += -funwind-tables CFLAGS-tst-backtrace4.c += -funwind-tables CFLAGS-tst-backtrace5.c += -funwind-tables +CFLAGS-tst-backtrace6.c += -funwind-tables LDFLAGS-tst-backtrace2 = -rdynamic LDFLAGS-tst-backtrace3 = -rdynamic LDFLAGS-tst-backtrace4 = -rdynamic LDFLAGS-tst-backtrace5 = -rdynamic +LDFLAGS-tst-backtrace6 = -rdynamic tests = backtrace-tst tst-longjmp_chk tst-chk1 tst-chk2 tst-chk3 \ tst-lfschk1 tst-lfschk2 tst-lfschk3 test-strcpy_chk test-stpcpy_chk \ tst-chk4 tst-chk5 tst-chk6 tst-lfschk4 tst-lfschk5 tst-lfschk6 \ tst-longjmp_chk2 tst-backtrace2 tst-backtrace3 tst-backtrace4 \ - tst-backtrace5 + tst-backtrace5 tst-backtrace6 tests-ifunc := $(stpcpy_chk strcpy_chk:%=test-%-ifunc) tests += $(tests-ifunc) diff --git a/debug/tst-backtrace5.c b/debug/tst-backtrace5.c index ca47437d92..51180c1c8c 100644 --- a/debug/tst-backtrace5.c +++ b/debug/tst-backtrace5.c @@ -28,6 +28,10 @@ #include "tst-backtrace.h" +#ifndef SIGACTION_FLAGS +# define SIGACTION_FLAGS 0 +#endif + static int do_test (void); #define TEST_FUNCTION do_test () #include "../test-skeleton.c" @@ -91,7 +95,7 @@ handle_signal (int signum) } NO_INLINE int -fn (int c) +fn (int c, int flags) { pid_t parent_pid, child_pid; int pipefd[2]; @@ -100,12 +104,13 @@ fn (int c) if (c > 0) { - fn (c - 1); + fn (c - 1, flags); return x; } memset (&act, 0, sizeof (act)); act.sa_handler = handle_signal; + act.sa_flags = flags; sigemptyset (&act.sa_mask); sigaction (SIGUSR1, &act, NULL); parent_pid = getpid (); @@ -131,6 +136,6 @@ fn (int c) NO_INLINE static int do_test (void) { - fn (2); + fn (2, SIGACTION_FLAGS); return ret; } diff --git a/debug/tst-backtrace6.c b/debug/tst-backtrace6.c new file mode 100644 index 0000000000..cd8dbcd1db --- /dev/null +++ b/debug/tst-backtrace6.c @@ -0,0 +1,21 @@ +/* Test backtrace and backtrace_symbols for signal frames, where a + system call was interrupted by a signal. + Copyright (C) 2013 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 + <http://www.gnu.org/licenses/>. */ + +#define SIGACTION_FLAGS SA_SIGINFO +#include <debug/tst-backtrace5.c> diff --git a/sysdeps/powerpc/powerpc32/backtrace.c b/sysdeps/powerpc/powerpc32/backtrace.c index b4b11dd03c..8d413e620f 100644 --- a/sysdeps/powerpc/powerpc32/backtrace.c +++ b/sysdeps/powerpc/powerpc32/backtrace.c @@ -18,6 +18,9 @@ #include <execinfo.h> #include <stddef.h> +#include <string.h> +#include <signal.h> +#include <bits/libc-vdso.h> /* This is the stack layout we see with every stack frame. Note that every routine is required by the ABI to lay out the stack @@ -35,6 +38,46 @@ struct layout void *return_address; }; +#define SIGNAL_FRAMESIZE 64 + +/* Since the signal handler is just like any other function it needs to + save/restore its LR and it will save it into callers stack frame. + Since a signal handler doesn't have a caller, the kernel creates a + dummy frame to make it look like it has a caller. */ +struct signal_frame_32 { + char dummy[SIGNAL_FRAMESIZE]; + struct sigcontext sctx; + mcontext_t mctx; + /* We don't care about the rest, since IP value is at 'mctx' field. */ +}; + +static inline int +is_sigtramp_address (unsigned int nip) +{ +#ifdef SHARED + if (nip == (unsigned int)__vdso_sigtramp32) + return 1; +#endif + return 0; +} + +struct rt_signal_frame_32 { + char dummy[SIGNAL_FRAMESIZE + 16]; + siginfo_t info; + struct ucontext uc; + /* We don't care about the rest, since IP value is at 'uc' field. */ +}; + +static inline int +is_sigtramp_address_rt (unsigned int nip) +{ +#ifdef SHARED + if (nip == (unsigned int)__vdso_sigtramp_rt32) + return 1; +#endif + return 0; +} + int __backtrace (void **array, int size) { @@ -50,7 +93,28 @@ __backtrace (void **array, int size) for ( count = 0; current != NULL && count < size; current = current->next, count++) - array[count] = current->return_address; + { + gregset_t *gregset = NULL; + + array[count] = current->return_address; + + /* Check if the symbol is the signal trampoline and get the interrupted + * symbol address from the trampoline saved area. */ + if (is_sigtramp_address ((unsigned int)current->return_address)) + { + struct signal_frame_32 *sigframe = + (struct signal_frame_32*) current; + gregset = &sigframe->mctx.gregs; + } + else if (is_sigtramp_address_rt ((unsigned int)current->return_address)) + { + struct rt_signal_frame_32 *sigframe = + (struct rt_signal_frame_32*) current; + gregset = &sigframe->uc.uc_mcontext.uc_regs->gregs; + } + if (gregset) + array[++count] = (void*)((*gregset)[PT_NIP]); + } /* It's possible the second-last stack frame can't return (that is, it's __libc_start_main), in which case diff --git a/sysdeps/powerpc/powerpc64/backtrace.c b/sysdeps/powerpc/powerpc64/backtrace.c index 2d3e051cb9..9b9a9f19da 100644 --- a/sysdeps/powerpc/powerpc64/backtrace.c +++ b/sysdeps/powerpc/powerpc64/backtrace.c @@ -18,6 +18,9 @@ #include <execinfo.h> #include <stddef.h> +#include <string.h> +#include <signal.h> +#include <bits/libc-vdso.h> /* This is the stack layout we see with every stack frame. Note that every routine is required by the ABI to lay out the stack @@ -38,6 +41,27 @@ struct layout void *return_address; }; +/* Since the signal handler is just like any other function it needs to + save/restore its LR and it will save it into callers stack frame. + Since a signal handler doesn't have a caller, the kernel creates a + dummy frame to make it look like it has a caller. */ +struct signal_frame_64 { +#define SIGNAL_FRAMESIZE 128 + char dummy[SIGNAL_FRAMESIZE]; + struct ucontext uc; + /* We don't care about the rest, since the IP value is at 'uc' field. */ +}; + +static inline int +is_sigtramp_address (unsigned long nip) +{ +#ifdef SHARED + if (nip == (unsigned long)__vdso_sigtramp_rt64) + return 1; +#endif + return 0; +} + int __backtrace (void **array, int size) { @@ -53,7 +77,17 @@ __backtrace (void **array, int size) for ( count = 0; current != NULL && count < size; current = current->next, count++) - array[count] = current->return_address; + { + array[count] = current->return_address; + + /* Check if the symbol is the signal trampoline and get the interrupted + * symbol address from the trampoline saved area. */ + if (is_sigtramp_address ((unsigned long)current->return_address)) + { + struct signal_frame_64 *sigframe = (struct signal_frame_64*) current; + array[++count] = (void*)sigframe->uc.uc_mcontext.gp_regs[PT_NIP]; + } + } /* It's possible the second-last stack frame can't return (that is, it's __libc_start_main), in which case diff --git a/sysdeps/unix/sysv/linux/powerpc/bits/libc-vdso.h b/sysdeps/unix/sysv/linux/powerpc/bits/libc-vdso.h index 8b195db1bf..ba54de4eb0 100644 --- a/sysdeps/unix/sysv/linux/powerpc/bits/libc-vdso.h +++ b/sysdeps/unix/sysv/linux/powerpc/bits/libc-vdso.h @@ -34,6 +34,13 @@ extern void *__vdso_getcpu; extern void *__vdso_time; +#if defined(__PPC64__) || defined(__powerpc64__) +extern void *__vdso_sigtramp_rt64; +#else +extern void *__vdso_sigtramp32; +extern void *__vdso_sigtramp_rt32; +#endif + /* This macro is needed for PPC64 to return a skeleton OPD entry of a vDSO symbol. This works because _dl_vdso_vsym always return the function address, and no vDSO symbols use the TOC or chain pointers from the OPD diff --git a/sysdeps/unix/sysv/linux/powerpc/init-first.c b/sysdeps/unix/sysv/linux/powerpc/init-first.c index f6f05f0ba2..061715f875 100644 --- a/sysdeps/unix/sysv/linux/powerpc/init-first.c +++ b/sysdeps/unix/sysv/linux/powerpc/init-first.c @@ -29,6 +29,12 @@ void *__vdso_clock_getres; void *__vdso_get_tbfreq; void *__vdso_getcpu; void *__vdso_time; +#if defined(__PPC64__) || defined(__powerpc64__) +void *__vdso_sigtramp_rt64; +#else +void *__vdso_sigtramp32; +void *__vdso_sigtramp_rt32; +#endif static inline void _libc_vdso_platform_setup (void) @@ -46,6 +52,16 @@ _libc_vdso_platform_setup (void) __vdso_getcpu = _dl_vdso_vsym ("__kernel_getcpu", &linux2615); __vdso_time = _dl_vdso_vsym ("__kernel_time", &linux2615); + + /* PPC64 uses only one signal trampoline symbol, while PPC32 will use + two depending if SA_SIGINFO is used (__kernel_sigtramp_rt32) or not + (__kernel_sigtramp32). */ +#if defined(__PPC64__) || defined(__powerpc64__) + __vdso_sigtramp_rt64 = _dl_vdso_vsym ("__kernel_sigtramp_rt64", &linux2615); +#else + __vdso_sigtramp32 = _dl_vdso_vsym ("__kernel_sigtramp32", &linux2615); + __vdso_sigtramp_rt32 = _dl_vdso_vsym ("__kernel_sigtramp_rt32", &linux2615); +#endif } # define VDSO_SETUP _libc_vdso_platform_setup |