+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]
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)
#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"
}
NO_INLINE int
-fn (int c)
+fn (int c, int flags)
{
pid_t parent_pid, child_pid;
int pipefd[2];
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 ();
NO_INLINE static int
do_test (void)
{
- fn (2);
+ fn (2, SIGACTION_FLAGS);
return ret;
}
--- /dev/null
+/* 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>
#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
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)
{
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
#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
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)
{
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
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
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)
__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
git://sourceware.org / glibc.git / commitdiff