[PATCH][PR sanitizer/77631] Support separate debug info in libbacktrace
Denis Khalikov
d.khalikov@partner.samsung.com
Mon Mar 13 17:16:00 GMT 2017
Hello everyone, i have a patch for this issue.
List of implemented functionality:
1.Reading .gnu_debuglink section from ELF file:
a. Reading name of debug info file.
b. Verifying crc32 sum.
2. Searching for separate debug info file from paths:
a. /usr/lib/debug/path/to/executable
b. /path/to/executable
c. /path/to/executable/.debug
Assumed that debug info file generated by objcopy from binutils.
objcopy --only-keep-debug foo foo.debug
strip -g foo
objcopy --add-gnu-debuglink=foo.debug foo
-------------- next part --------------
commit 6147ee1a9aeeb748563a8998033f2ce195460162
Author: Denis Khalikov <d.khalikov@partner.samsung.com>
Date: Mon Mar 13 18:55:36 2017 +0300
PR sanitizer/77631
* Makefile.am: Update to support glinktest.
* Makefile.in: Regenerated.
* configure.ac: Add AC_CHECK_PROG for objcopy.
* configure: Regenerated.
* elf.c (elf_header_is_valid): New function. Verify elf header.
(elf_add): Move code which reads elf header to elf_header_is_valid.
(elf_gnu_debuglink_section): New function. Read debuglink section from
elf.
(phdr_callback): Call backtrace_open_debugfile function for shared
library.
* fileline.c (fileline_initialize): Call backtrace_open_debugfile
function for executable.
* glinktest.c: New test.
* internal.h (MAX_PATH_LEN): Defined new variable.
* posix.c (enum type_of_file): New enum.
(enum debug_path): New enum.
(getl32): New function.
(gnu_debuglink_crc32): New function. Generate crc32 sum.
(get_crc32): New function.
(pathlen): New function.
(check_sum): New function. Verify sum.
(get_debug_filename_len): New function.
(backtrace_readlink): New function.
(backtrace_open_debugfile): New function.
diff --git a/libbacktrace/ChangeLog b/libbacktrace/ChangeLog
index 25cd921..cec5d3f 100644
--- a/libbacktrace/ChangeLog
+++ b/libbacktrace/ChangeLog
@@ -1,3 +1,30 @@
+2017-03-13 Denis Khalikov <d.khalikov@partner.samsung.com>
+
+ PR sanitizer/77631
+ * Makefile.am: Update to support glinktest.
+ * Makefile.in: Regenerated.
+ * configure: Add script to find objcopy in the system.
+ * elf.c (elf_header_is_valid): New function. Verify elf header.
+ (elf_add): Move code which reads elf header to elf_header_is_valid.
+ (elf_gnu_debuglink_section): New function. Read debuglink section from
+ elf.
+ (phdr_callback): Call backtrace_open_debugfile function for shared
+ library.
+ * fileline.c (fileline_initialize): Call backtrace_open_debugfile
+ function for executable.
+ * glinktest.c: New test.
+ * internal.h (MAX_PATH_LEN): Defined new variable.
+ * posix.c (enum type_of_file): New enum.
+ (enum debug_path): New enum.
+ (getl32): New function.
+ (gnu_debuglink_crc32): New function. Generate crc32 sum.
+ (get_crc32): New function.
+ (pathlen): New function.
+ (check_sum): New function. Verify sum.
+ (get_debug_filename_len): New function.
+ (backtrace_readlink): New function.
+ (backtrace_open_debugfile): New function.
+
2017-03-08 Sam Thursfield <sam.thursfield@codethink.co.uk>
* btest.c (test5): Replace #ifdef guard with 'unused' attribute
diff --git a/libbacktrace/Makefile.am b/libbacktrace/Makefile.am
index 344dad5..17460a5 100644
--- a/libbacktrace/Makefile.am
+++ b/libbacktrace/Makefile.am
@@ -81,6 +81,17 @@ libbacktrace_la_LIBADD = \
libbacktrace_la_DEPENDENCIES = $(libbacktrace_la_LIBADD)
+clean_separate:glinktest.debug
+ rm -f glinktest.debug
+
+separate: glinktest
+ if test -n "$(OBJCOPY)" && test -n "$(STRIP)"; \
+ then \
+ $(OBJCOPY) --only-keep-debug glinktest glinktest.debug;\
+ $(STRIP) glinktest;\
+ $(OBJCOPY) --add-gnu-debuglink=glinktest.debug glinktest;\
+ fi;
+
# Testsuite.
check_PROGRAMS =
@@ -100,6 +111,12 @@ stest_LDADD = libbacktrace.la
check_PROGRAMS += stest
+glinktest_SOURCES = glinktest.c
+glinktest_CFLAGS = $(AM_CFLAGS) -g -O
+glinktest_LDADD = libbacktrace.la
+
+check_PROGRAMS += glinktest
+
endif NATIVE
# We can't use automake's automatic dependency tracking, because it
@@ -134,3 +151,4 @@ sort.lo: config.h backtrace.h internal.h
stest.lo: config.h backtrace.h internal.h
state.lo: config.h backtrace.h backtrace-supported.h internal.h
unknown.lo: config.h backtrace.h internal.h
+glinktest.lo: (INCDIR)/filenames.h backtrace.h backtrace-supported.h
diff --git a/libbacktrace/Makefile.in b/libbacktrace/Makefile.in
index de74b5d..354ecc7 100644
--- a/libbacktrace/Makefile.in
+++ b/libbacktrace/Makefile.in
@@ -84,7 +84,7 @@ build_triplet = @build@
host_triplet = @host@
target_triplet = @target@
check_PROGRAMS = $(am__EXEEXT_1)
-@NATIVE_TRUE@am__append_1 = btest stest
+@NATIVE_TRUE@am__append_1 = btest stest glinktest
subdir = .
DIST_COMMON = README ChangeLog $(srcdir)/Makefile.in \
$(srcdir)/Makefile.am $(top_srcdir)/configure \
@@ -113,13 +113,20 @@ am__DEPENDENCIES_1 =
am_libbacktrace_la_OBJECTS = atomic.lo dwarf.lo fileline.lo posix.lo \
print.lo sort.lo state.lo
libbacktrace_la_OBJECTS = $(am_libbacktrace_la_OBJECTS)
-@NATIVE_TRUE@am__EXEEXT_1 = btest$(EXEEXT) stest$(EXEEXT)
+@NATIVE_TRUE@am__EXEEXT_1 = btest$(EXEEXT) stest$(EXEEXT) \
+@NATIVE_TRUE@ glinktest$(EXEEXT)
@NATIVE_TRUE@am_btest_OBJECTS = btest-btest.$(OBJEXT)
btest_OBJECTS = $(am_btest_OBJECTS)
@NATIVE_TRUE@btest_DEPENDENCIES = libbacktrace.la
btest_LINK = $(LIBTOOL) --tag=CC $(AM_LIBTOOLFLAGS) $(LIBTOOLFLAGS) \
--mode=link $(CCLD) $(btest_CFLAGS) $(CFLAGS) $(AM_LDFLAGS) \
$(LDFLAGS) -o $@
+@NATIVE_TRUE@am_glinktest_OBJECTS = glinktest-glinktest.$(OBJEXT)
+glinktest_OBJECTS = $(am_glinktest_OBJECTS)
+@NATIVE_TRUE@glinktest_DEPENDENCIES = libbacktrace.la
+glinktest_LINK = $(LIBTOOL) --tag=CC $(AM_LIBTOOLFLAGS) \
+ $(LIBTOOLFLAGS) --mode=link $(CCLD) $(glinktest_CFLAGS) \
+ $(CFLAGS) $(AM_LDFLAGS) $(LDFLAGS) -o $@
@NATIVE_TRUE@am_stest_OBJECTS = stest.$(OBJEXT)
stest_OBJECTS = $(am_stest_OBJECTS)
@NATIVE_TRUE@stest_DEPENDENCIES = libbacktrace.la
@@ -136,7 +143,7 @@ LINK = $(LIBTOOL) --tag=CC $(AM_LIBTOOLFLAGS) $(LIBTOOLFLAGS) \
--mode=link $(CCLD) $(AM_CFLAGS) $(CFLAGS) $(AM_LDFLAGS) \
$(LDFLAGS) -o $@
SOURCES = $(libbacktrace_la_SOURCES) $(EXTRA_libbacktrace_la_SOURCES) \
- $(btest_SOURCES) $(stest_SOURCES)
+ $(btest_SOURCES) $(glinktest_SOURCES) $(stest_SOURCES)
MULTISRCTOP =
MULTIBUILDTOP =
MULTIDIRS =
@@ -200,6 +207,7 @@ MAKEINFO = @MAKEINFO@
MKDIR_P = @MKDIR_P@
NM = @NM@
NMEDIT = @NMEDIT@
+OBJCOPY = @OBJCOPY@
OBJDUMP = @OBJDUMP@
OBJEXT = @OBJEXT@
OTOOL = @OTOOL@
@@ -330,6 +338,9 @@ TESTS = $(check_PROGRAMS)
@NATIVE_TRUE@btest_LDADD = libbacktrace.la
@NATIVE_TRUE@stest_SOURCES = stest.c
@NATIVE_TRUE@stest_LDADD = libbacktrace.la
+@NATIVE_TRUE@glinktest_SOURCES = glinktest.c
+@NATIVE_TRUE@glinktest_CFLAGS = $(AM_CFLAGS) -g -O
+@NATIVE_TRUE@glinktest_LDADD = libbacktrace.la
# We can't use automake's automatic dependency tracking, because it
# breaks when using bootstrap-lean. Automatic dependency tracking
@@ -422,6 +433,9 @@ clean-checkPROGRAMS:
btest$(EXEEXT): $(btest_OBJECTS) $(btest_DEPENDENCIES) $(EXTRA_btest_DEPENDENCIES)
@rm -f btest$(EXEEXT)
$(btest_LINK) $(btest_OBJECTS) $(btest_LDADD) $(LIBS)
+glinktest$(EXEEXT): $(glinktest_OBJECTS) $(glinktest_DEPENDENCIES) $(EXTRA_glinktest_DEPENDENCIES)
+ @rm -f glinktest$(EXEEXT)
+ $(glinktest_LINK) $(glinktest_OBJECTS) $(glinktest_LDADD) $(LIBS)
stest$(EXEEXT): $(stest_OBJECTS) $(stest_DEPENDENCIES) $(EXTRA_stest_DEPENDENCIES)
@rm -f stest$(EXEEXT)
$(LINK) $(stest_OBJECTS) $(stest_LDADD) $(LIBS)
@@ -447,6 +461,12 @@ btest-btest.o: btest.c
btest-btest.obj: btest.c
$(CC) $(DEFS) $(DEFAULT_INCLUDES) $(INCLUDES) $(AM_CPPFLAGS) $(CPPFLAGS) $(btest_CFLAGS) $(CFLAGS) -c -o btest-btest.obj `if test -f 'btest.c'; then $(CYGPATH_W) 'btest.c'; else $(CYGPATH_W) '$(srcdir)/btest.c'; fi`
+glinktest-glinktest.o: glinktest.c
+ $(CC) $(DEFS) $(DEFAULT_INCLUDES) $(INCLUDES) $(AM_CPPFLAGS) $(CPPFLAGS) $(glinktest_CFLAGS) $(CFLAGS) -c -o glinktest-glinktest.o `test -f 'glinktest.c' || echo '$(srcdir)/'`glinktest.c
+
+glinktest-glinktest.obj: glinktest.c
+ $(CC) $(DEFS) $(DEFAULT_INCLUDES) $(INCLUDES) $(AM_CPPFLAGS) $(CPPFLAGS) $(glinktest_CFLAGS) $(CFLAGS) -c -o glinktest-glinktest.obj `if test -f 'glinktest.c'; then $(CYGPATH_W) 'glinktest.c'; else $(CYGPATH_W) '$(srcdir)/glinktest.c'; fi`
+
mostlyclean-libtool:
-rm -f *.lo
@@ -745,6 +765,17 @@ uninstall-am:
mostlyclean-multi pdf pdf-am ps ps-am tags uninstall \
uninstall-am
+
+clean_separate:glinktest.debug
+ rm -f glinktest.debug
+
+separate: glinktest
+ if test -n "$(OBJCOPY)" && test -n "$(STRIP)"; \
+ then \
+ $(OBJCOPY) --only-keep-debug glinktest glinktest.debug;\
+ $(STRIP) glinktest;\
+ $(OBJCOPY) --add-gnu-debuglink=glinktest.debug glinktest;\
+ fi;
alloc.lo: config.h backtrace.h internal.h
backtrace.lo: config.h backtrace.h internal.h
btest.lo: (INCDIR)/filenames.h backtrace.h backtrace-supported.h
@@ -764,6 +795,7 @@ sort.lo: config.h backtrace.h internal.h
stest.lo: config.h backtrace.h internal.h
state.lo: config.h backtrace.h backtrace-supported.h internal.h
unknown.lo: config.h backtrace.h internal.h
+glinktest.lo: (INCDIR)/filenames.h backtrace.h backtrace-supported.h
# Tell versions [3.59,3.63) of GNU make to not export all variables.
# Otherwise a system limit (for SysV at least) may be exceeded.
diff --git a/libbacktrace/configure b/libbacktrace/configure
index ee90bc6..dda8b09 100755
--- a/libbacktrace/configure
+++ b/libbacktrace/configure
@@ -630,6 +630,7 @@ LD
FGREP
SED
LIBTOOL
+OBJCOPY
RANLIB
MAINT
MAINTAINER_MODE_FALSE
@@ -5011,6 +5012,44 @@ else
fi
+# Extract the first word of "objcopy", so it can be a program name with args.
+set dummy objcopy; ac_word=$2
+{ $as_echo "$as_me:${as_lineno-$LINENO}: checking for $ac_word" >&5
+$as_echo_n "checking for $ac_word... " >&6; }
+if test "${ac_cv_prog_OBJCOPY+set}" = set; then :
+ $as_echo_n "(cached) " >&6
+else
+ if test -n "$OBJCOPY"; then
+ ac_cv_prog_OBJCOPY="$OBJCOPY" # Let the user override the test.
+else
+as_save_IFS=$IFS; IFS=$PATH_SEPARATOR
+for as_dir in $PATH
+do
+ IFS=$as_save_IFS
+ test -z "$as_dir" && as_dir=.
+ for ac_exec_ext in '' $ac_executable_extensions; do
+ if { test -f "$as_dir/$ac_word$ac_exec_ext" && $as_test_x "$as_dir/$ac_word$ac_exec_ext"; }; then
+ ac_cv_prog_OBJCOPY="objcopy"
+ $as_echo "$as_me:${as_lineno-$LINENO}: found $as_dir/$ac_word$ac_exec_ext" >&5
+ break 2
+ fi
+done
+ done
+IFS=$as_save_IFS
+
+fi
+fi
+OBJCOPY=$ac_cv_prog_OBJCOPY
+if test -n "$OBJCOPY"; then
+ { $as_echo "$as_me:${as_lineno-$LINENO}: result: $OBJCOPY" >&5
+$as_echo "$OBJCOPY" >&6; }
+else
+ { $as_echo "$as_me:${as_lineno-$LINENO}: result: no" >&5
+$as_echo "no" >&6; }
+fi
+
+
+
for ac_prog in gawk mawk nawk awk
do
# Extract the first word of "$ac_prog", so it can be a program name with args.
@@ -11131,7 +11170,7 @@ else
lt_dlunknown=0; lt_dlno_uscore=1; lt_dlneed_uscore=2
lt_status=$lt_dlunknown
cat > conftest.$ac_ext <<_LT_EOF
-#line 11134 "configure"
+#line 11173 "configure"
#include "confdefs.h"
#if HAVE_DLFCN_H
@@ -11237,7 +11276,7 @@ else
lt_dlunknown=0; lt_dlno_uscore=1; lt_dlneed_uscore=2
lt_status=$lt_dlunknown
cat > conftest.$ac_ext <<_LT_EOF
-#line 11240 "configure"
+#line 11279 "configure"
#include "confdefs.h"
#if HAVE_DLFCN_H
diff --git a/libbacktrace/configure.ac b/libbacktrace/configure.ac
index f9cad21..9e1e4c4 100644
--- a/libbacktrace/configure.ac
+++ b/libbacktrace/configure.ac
@@ -74,6 +74,8 @@ AC_SUBST(CFLAGS)
AC_PROG_RANLIB
+AC_CHECK_PROG(OBJCOPY, objcopy, objcopy)
+
AC_PROG_AWK
case "$AWK" in
"") AC_MSG_ERROR([can't build without awk]) ;;
diff --git a/libbacktrace/elf.c b/libbacktrace/elf.c
index 89ed42b..697a8c9 100644
--- a/libbacktrace/elf.c
+++ b/libbacktrace/elf.c
@@ -510,70 +510,34 @@ elf_syminfo (struct backtrace_state *state, uintptr_t addr,
callback (data, addr, sym->name, sym->address, sym->size);
}
-/* Add the backtrace data for one ELF file. Returns 1 on success,
- 0 on failure (in both cases descriptor is closed) or -1 if exe
- is non-zero and the ELF file is ET_DYN, which tells the caller that
- elf_add will need to be called on the descriptor again after
- base_address is determined. */
+/* Return 1 if header is valid and -1 on fail */
static int
-elf_add (struct backtrace_state *state, int descriptor, uintptr_t base_address,
- backtrace_error_callback error_callback, void *data,
- fileline *fileline_fn, int *found_sym, int *found_dwarf, int exe)
+elf_header_is_valid (struct backtrace_state *state, int descriptor,
+ backtrace_error_callback error_callback, void *data, int exe,
+ off_t *shoff_out, unsigned int *shnum_out,
+ unsigned int *shstrndx_out, b_elf_ehdr *ehdr_out)
{
- struct backtrace_view ehdr_view;
- b_elf_ehdr ehdr;
- off_t shoff;
- unsigned int shnum;
- unsigned int shstrndx;
- struct backtrace_view shdrs_view;
- int shdrs_view_valid;
- const b_elf_shdr *shdrs;
- const b_elf_shdr *shstrhdr;
- size_t shstr_size;
- off_t shstr_off;
- struct backtrace_view names_view;
- int names_view_valid;
- const char *names;
- unsigned int symtab_shndx;
- unsigned int dynsym_shndx;
- unsigned int i;
- struct debug_section_info sections[DEBUG_MAX];
- struct backtrace_view symtab_view;
- int symtab_view_valid;
- struct backtrace_view strtab_view;
- int strtab_view_valid;
- off_t min_offset;
- off_t max_offset;
- struct backtrace_view debug_view;
- int debug_view_valid;
-
- *found_sym = 0;
- *found_dwarf = 0;
- shdrs_view_valid = 0;
- names_view_valid = 0;
- symtab_view_valid = 0;
- strtab_view_valid = 0;
- debug_view_valid = 0;
+ struct backtrace_view ehdr_view;
- if (!backtrace_get_view (state, descriptor, 0, sizeof ehdr, error_callback,
- data, &ehdr_view))
+ if (!backtrace_get_view (state, descriptor, 0, sizeof *ehdr_out,
+ error_callback, data, &ehdr_view))
goto fail;
- memcpy (&ehdr, ehdr_view.data, sizeof ehdr);
+ memcpy (ehdr_out, ehdr_view.data, sizeof *ehdr_out);
backtrace_release_view (state, &ehdr_view, error_callback, data);
- if (ehdr.e_ident[EI_MAG0] != ELFMAG0
- || ehdr.e_ident[EI_MAG1] != ELFMAG1
- || ehdr.e_ident[EI_MAG2] != ELFMAG2
- || ehdr.e_ident[EI_MAG3] != ELFMAG3)
+ if (ehdr_out->e_ident[EI_MAG0] != ELFMAG0
+ || ehdr_out->e_ident[EI_MAG1] != ELFMAG1
+ || ehdr_out->e_ident[EI_MAG2] != ELFMAG2
+ || ehdr_out->e_ident[EI_MAG3] != ELFMAG3)
{
error_callback (data, "executable file is not ELF", 0);
goto fail;
}
- if (ehdr.e_ident[EI_VERSION] != EV_CURRENT)
+ if (ehdr_out->e_ident[EI_VERSION] != EV_CURRENT)
{
error_callback (data, "executable file is unrecognized ELF version", 0);
goto fail;
@@ -585,14 +549,14 @@ elf_add (struct backtrace_state *state, int descriptor, uintptr_t base_address,
#define BACKTRACE_ELFCLASS ELFCLASS64
#endif
- if (ehdr.e_ident[EI_CLASS] != BACKTRACE_ELFCLASS)
+ if (ehdr_out->e_ident[EI_CLASS] != BACKTRACE_ELFCLASS)
{
error_callback (data, "executable file is unexpected ELF class", 0);
goto fail;
}
- if (ehdr.e_ident[EI_DATA] != ELFDATA2LSB
- && ehdr.e_ident[EI_DATA] != ELFDATA2MSB)
+ if (ehdr_out->e_ident[EI_DATA] != ELFDATA2LSB
+ && ehdr_out->e_ident[EI_DATA] != ELFDATA2MSB)
{
error_callback (data, "executable file has unknown endianness", 0);
goto fail;
@@ -601,31 +565,30 @@ elf_add (struct backtrace_state *state, int descriptor, uintptr_t base_address,
/* If the executable is ET_DYN, it is either a PIE, or we are running
directly a shared library with .interp. We need to wait for
dl_iterate_phdr in that case to determine the actual base_address. */
- if (exe && ehdr.e_type == ET_DYN)
+ if (exe && ehdr_out->e_type == ET_DYN)
return -1;
- shoff = ehdr.e_shoff;
- shnum = ehdr.e_shnum;
- shstrndx = ehdr.e_shstrndx;
+ *shoff_out = ehdr_out->e_shoff;
+ *shnum_out = ehdr_out->e_shnum;
+ *shstrndx_out = ehdr_out->e_shstrndx;
- if ((shnum == 0 || shstrndx == SHN_XINDEX)
- && shoff != 0)
+ if ((*shnum_out == 0 || *shstrndx_out == SHN_XINDEX) && *shoff_out != 0)
{
struct backtrace_view shdr_view;
const b_elf_shdr *shdr;
- if (!backtrace_get_view (state, descriptor, shoff, sizeof shdr,
+ if (!backtrace_get_view (state, descriptor, *shoff_out, sizeof shdr,
error_callback, data, &shdr_view))
goto fail;
shdr = (const b_elf_shdr *) shdr_view.data;
- if (shnum == 0)
- shnum = shdr->sh_size;
+ if (*shnum_out == 0)
+ *shnum_out = shdr->sh_size;
- if (shstrndx == SHN_XINDEX)
+ if (*shstrndx_out == SHN_XINDEX)
{
- shstrndx = shdr->sh_link;
+ *shstrndx_out = shdr->sh_link;
/* Versions of the GNU binutils between 2.12 and 2.18 did
not handle objects with more than SHN_LORESERVE sections
@@ -638,21 +601,173 @@ elf_add (struct backtrace_state *state, int descriptor, uintptr_t base_address,
section header string table index is larger than the
number of sections, then we know we have to subtract
0x100 to get the real section index. */
- if (shstrndx >= shnum && shstrndx >= SHN_LORESERVE + 0x100)
- shstrndx -= 0x100;
+ if (*shstrndx_out >= *shnum_out
+ && *shstrndx_out >= SHN_LORESERVE + 0x100)
+ *shstrndx_out -= 0x100;
}
-
backtrace_release_view (state, &shdr_view, error_callback, data);
}
+ return 1;
+fail:
+ return -1;
+}
+
+/* Return the pointer to char array with data from .gnudebuglink section inside. */
+
+unsigned char *
+elf_gnu_debuglink_section (struct backtrace_state *state, int descriptor,
+ backtrace_error_callback error_callback, void *data,
+ int exe, int *gnulink_data_len_out)
+{
+ b_elf_ehdr ehdr;
+ off_t shoff;
+ unsigned int shnum;
+ unsigned int shstrndx;
+ struct backtrace_view shdrs_view;
+ int shdrs_view_valid;
+ const b_elf_shdr *shdrs;
+ const b_elf_shdr *shstrhdr;
+ size_t shstr_size;
+ off_t shstr_off;
+ struct backtrace_view names_view;
+ struct backtrace_view gnulink_view;
+ int names_view_valid;
+ const char *names;
+ unsigned int i;
+ int gnulink_view_valid;
+ unsigned char *gnulink_data;
+
+ gnulink_view_valid = 0;
+ shdrs_view_valid = 0;
+ names_view_valid = 0;
+ gnulink_data = NULL;
+
+ if (!elf_header_is_valid (state, descriptor, error_callback, data, exe, &shoff,
+ &shnum, &shstrndx, &ehdr))
+ goto exit;
+
+ if (!backtrace_get_view (state, descriptor, shoff + sizeof (b_elf_shdr),
+ (shnum - 1) * sizeof (b_elf_shdr), error_callback,
+ data, &shdrs_view))
+ goto exit;
+
+ shdrs_view_valid = 1;
+ shdrs = (const b_elf_shdr *) shdrs_view.data;
+
+ /* Read the section names. */
+
+ shstrhdr = &shdrs[shstrndx - 1];
+ shstr_size = shstrhdr->sh_size;
+ shstr_off = shstrhdr->sh_offset;
+
+ if (!backtrace_get_view (state, descriptor, shstr_off, shstr_size,
+ error_callback, data, &names_view))
+ goto exit;
+
+ names_view_valid = 1;
+ names = (const char *) names_view.data;
+
+ /* Look for for the .gnu_debuglink section */
+ for (i = 1; i < shnum; ++i)
+ {
+ const b_elf_shdr *shdr;
+ unsigned int sh_name;
+ const char *name;
+ shdr = &shdrs[i - 1];
+ sh_name = shdr->sh_name;
+ if (sh_name >= shstr_size)
+ {
+ error_callback (data, "ELF section name out of range", 0);
+ goto exit;
+ }
+ name = names + sh_name;
+ if (strcmp (name, ".gnu_debuglink") == 0)
+ {
+ if (backtrace_get_view (state, descriptor, shdr->sh_offset,
+ shdr->sh_size, error_callback, data,
+ &gnulink_view))
+ {
+
+ gnulink_view_valid = 1;
+ gnulink_data
+ = backtrace_alloc (state, shdr->sh_size, error_callback, data);
+ if (gnulink_data == NULL)
+ goto exit;
+ memcpy (gnulink_data, gnulink_view.data, shdr->sh_size);
+ *gnulink_data_len_out = shdr->sh_size;
+ }
+ break;
+ }
+ }
+
+exit:
+ if (shdrs_view_valid)
+ backtrace_release_view (state, &shdrs_view, error_callback, data);
+ if (names_view_valid)
+ backtrace_release_view (state, &names_view, error_callback, data);
+ if (gnulink_view_valid)
+ backtrace_release_view (state, &gnulink_view, error_callback, data);
+ return gnulink_data;
+}
+
+/* Add the backtrace data for one ELF file. Returns 1 on success,
+ 0 on failure (in both cases descriptor is closed) or -1 if exe
+ is non-zero and the ELF file is ET_DYN, which tells the caller that
+ elf_add will need to be called on the descriptor again after
+ base_address is determined. */
+
+static int
+elf_add (struct backtrace_state *state, int descriptor, uintptr_t base_address,
+ backtrace_error_callback error_callback, void *data,
+ fileline *fileline_fn, int *found_sym, int *found_dwarf, int exe)
+{
+ b_elf_ehdr ehdr;
+ off_t shoff;
+ unsigned int shnum;
+ unsigned int shstrndx;
+ struct backtrace_view shdrs_view;
+ int shdrs_view_valid;
+ const b_elf_shdr *shdrs;
+ const b_elf_shdr *shstrhdr;
+ size_t shstr_size;
+ off_t shstr_off;
+ struct backtrace_view names_view;
+ int names_view_valid;
+ const char *names;
+ unsigned int symtab_shndx;
+ unsigned int dynsym_shndx;
+ unsigned int i;
+ struct debug_section_info sections[DEBUG_MAX];
+ struct backtrace_view symtab_view;
+ int symtab_view_valid;
+ struct backtrace_view strtab_view;
+ int strtab_view_valid;
+ off_t min_offset;
+ off_t max_offset;
+ struct backtrace_view debug_view;
+ int debug_view_valid;
+
+ *found_sym = 0;
+ *found_dwarf = 0;
+
+ shdrs_view_valid = 0;
+ names_view_valid = 0;
+ symtab_view_valid = 0;
+ strtab_view_valid = 0;
+ debug_view_valid = 0;
+
+ if (!elf_header_is_valid (state, descriptor, error_callback, data, exe, &shoff,
+ &shnum, &shstrndx, &ehdr))
+ goto fail;
/* To translate PC to file/line when using DWARF, we need to find
- the .debug_info and .debug_line sections. */
+ the .debug_info and .debug_line sections. */
/* Read the section headers, skipping the first one. */
if (!backtrace_get_view (state, descriptor, shoff + sizeof (b_elf_shdr),
- (shnum - 1) * sizeof (b_elf_shdr),
- error_callback, data, &shdrs_view))
+ (shnum - 1) * sizeof (b_elf_shdr), error_callback,
+ data, &shdrs_view))
goto fail;
shdrs_view_valid = 1;
shdrs = (const b_elf_shdr *) shdrs_view.data;
@@ -877,6 +992,7 @@ phdr_callback (struct dl_phdr_info *info, size_t size ATTRIBUTE_UNUSED,
int does_not_exist;
fileline elf_fileline_fn;
int found_dwarf;
+ int debugfile_does_not_exist;
/* There is not much we can do if we don't have the module name,
unless executable is ET_DYN, where we expect the very first
@@ -896,8 +1012,12 @@ phdr_callback (struct dl_phdr_info *info, size_t size ATTRIBUTE_UNUSED,
pd->exe_descriptor = -1;
}
- descriptor = backtrace_open (info->dlpi_name, pd->error_callback,
- pd->data, &does_not_exist);
+ descriptor
+ = backtrace_open_debugfile (info->dlpi_name, pd->error_callback, pd->data,
+ &debugfile_does_not_exist, pd->state, 0);
+ if (descriptor < 0)
+ descriptor = backtrace_open (info->dlpi_name, pd->error_callback,
+ pd->data, &does_not_exist);
if (descriptor < 0)
return 0;
}
diff --git a/libbacktrace/fileline.c b/libbacktrace/fileline.c
index 0fd350a..5699a8e 100644
--- a/libbacktrace/fileline.c
+++ b/libbacktrace/fileline.c
@@ -84,6 +84,7 @@ fileline_initialize (struct backtrace_state *state,
{
const char *filename;
int does_not_exist;
+ int debugfile_does_not_exist;
switch (pass)
{
@@ -106,8 +107,14 @@ fileline_initialize (struct backtrace_state *state,
if (filename == NULL)
continue;
- descriptor = backtrace_open (filename, error_callback, data,
- &does_not_exist);
+ descriptor
+ = backtrace_open_debugfile (filename, error_callback, data,
+ &debugfile_does_not_exist, state, 1);
+
+ if (descriptor < 0)
+ descriptor
+ = backtrace_open (filename, error_callback, data, &does_not_exist);
+
if (descriptor < 0 && !does_not_exist)
{
called_error_callback = 1;
diff --git a/libbacktrace/glinktest.c b/libbacktrace/glinktest.c
new file mode 100644
index 0000000..1a86b43
--- /dev/null
+++ b/libbacktrace/glinktest.c
@@ -0,0 +1,365 @@
+/* glinktest.c -- Test for libbacktrace library
+ Copyright (C) 2012-2017 Free Software Foundation, Inc.
+ Written by Ian Lance Taylor, Google.
+
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions are
+met:
+
+ (1) Redistributions of source code must retain the above copyright
+ notice, this list of conditions and the following disclaimer.
+
+ (2) Redistributions in binary form must reproduce the above copyright
+ notice, this list of conditions and the following disclaimer in
+ the documentation and/or other materials provided with the
+ distribution.
+
+ (3) The name of the author may not be used to
+ endorse or promote products derived from this software without
+ specific prior written permission.
+
+THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
+IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
+WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
+DISCLAIMED. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT,
+INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
+(INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
+SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
+STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING
+IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
+POSSIBILITY OF SUCH DAMAGE. */
+
+/* This program tests the externally visible interfaces of the
+ libbacktrace library. */
+
+#include <assert.h>
+#include <stdio.h>
+#include <string.h>
+#include <stdlib.h>
+
+#include "backtrace.h"
+#include "backtrace-supported.h"
+#ifndef GCC_VERSION
+#define GCC_VERSION (__GNUC__ * 1000 + __GNUC_MINOR__)
+#endif
+
+#if (GCC_VERSION < 2007)
+#define __attribute__(x)
+#endif
+
+#ifndef ATTRIBUTE_UNUSED
+#define ATTRIBUTE_UNUSED __attribute__ ((__unused__))
+#endif
+
+/* Used to collect backtrace info. */
+
+/*Just a simple test copied from btest.c, but in this case we don't have debug
+ * info in the executable and test should verify that we can read debug info
+ * from separate file. See Makefile check-TESTS target. */
+
+struct info
+{
+ char *filename;
+ int lineno;
+ char *function;
+};
+
+/* Passed to backtrace callback function. */
+
+struct bdata
+{
+ struct info *all;
+ size_t index;
+ size_t max;
+ int failed;
+};
+
+/* Passed to backtrace_simple callback function. */
+
+struct sdata
+{
+ uintptr_t *addrs;
+ size_t index;
+ size_t max;
+ int failed;
+};
+
+/* Passed to backtrace_syminfo callback function. */
+
+struct symdata
+{
+ const char *name;
+ uintptr_t val, size;
+ int failed;
+};
+
+/* The backtrace state. */
+
+static void *state;
+
+/* The number of failures. */
+
+static int failures;
+
+/* The backtrace callback function. */
+
+static int
+callback_one (void *vdata, uintptr_t pc ATTRIBUTE_UNUSED, const char *filename,
+ int lineno, const char *function)
+{
+ struct bdata *data = (struct bdata *) vdata;
+ struct info *p;
+
+ if (data->index >= data->max)
+ {
+ fprintf (stderr, "callback_one: callback called too many times\n");
+ data->failed = 1;
+ return 1;
+ }
+
+ p = &data->all[data->index];
+ if (filename == NULL)
+ p->filename = NULL;
+ else
+ {
+ p->filename = strdup (filename);
+ assert (p->filename != NULL);
+ }
+ p->lineno = lineno;
+ if (function == NULL)
+ p->function = NULL;
+ else
+ {
+ p->function = strdup (function);
+ assert (p->function != NULL);
+ }
+ ++data->index;
+
+ return 0;
+}
+
+/* An error callback passed to backtrace. */
+
+static void
+error_callback_one (void *vdata, const char *msg, int errnum)
+{
+ struct bdata *data = (struct bdata *) vdata;
+
+ fprintf (stderr, "%s", msg);
+ if (errnum > 0)
+ fprintf (stderr, ": %s", strerror (errnum));
+ fprintf (stderr, "\n");
+ data->failed = 1;
+}
+
+/* The backtrace_simple callback function. */
+
+static int
+callback_two (void *vdata, uintptr_t pc)
+{
+ struct sdata *data = (struct sdata *) vdata;
+
+ if (data->index >= data->max)
+ {
+ fprintf (stderr, "callback_two: callback called too many times\n");
+ data->failed = 1;
+ return 1;
+ }
+
+ data->addrs[data->index] = pc;
+ ++data->index;
+
+ return 0;
+}
+
+/* An error callback passed to backtrace_simple. */
+
+static void
+error_callback_two (void *vdata, const char *msg, int errnum)
+{
+ struct sdata *data = (struct sdata *) vdata;
+
+ fprintf (stderr, "%s", msg);
+ if (errnum > 0)
+ fprintf (stderr, ": %s", strerror (errnum));
+ fprintf (stderr, "\n");
+ data->failed = 1;
+}
+
+/* The backtrace_syminfo callback function. */
+
+static void
+callback_three (void *vdata, uintptr_t pc ATTRIBUTE_UNUSED, const char *symname,
+ uintptr_t symval, uintptr_t symsize)
+{
+ struct symdata *data = (struct symdata *) vdata;
+
+ if (symname == NULL)
+ data->name = NULL;
+ else
+ {
+ data->name = strdup (symname);
+ assert (data->name != NULL);
+ }
+ data->val = symval;
+ data->size = symsize;
+}
+
+/* The backtrace_syminfo error callback function. */
+
+static void
+error_callback_three (void *vdata, const char *msg, int errnum)
+{
+ struct symdata *data = (struct symdata *) vdata;
+
+ fprintf (stderr, "%s", msg);
+ if (errnum > 0)
+ fprintf (stderr, ": %s", strerror (errnum));
+ fprintf (stderr, "\n");
+ data->failed = 1;
+}
+
+static void
+error_callback_create (void *data ATTRIBUTE_UNUSED, const char *msg, int errnum)
+{
+ fprintf (stderr, "%s", msg);
+ if (errnum > 0)
+ fprintf (stderr, ": %s", strerror (errnum));
+ fprintf (stderr, "\n");
+ exit (EXIT_FAILURE);
+}
+
+static int
+f23 (void)
+{
+ uintptr_t addrs[20];
+ struct sdata data;
+ int i;
+
+ data.addrs = &addrs[0];
+ data.index = 0;
+ data.max = 20;
+ data.failed = 0;
+
+ i = backtrace_simple (state, 0, callback_two, error_callback_two, &data);
+
+ if (i != 0)
+ {
+ fprintf (stderr, "test3: unexpected return value %d\n", i);
+ data.failed = 1;
+ }
+
+ if (!data.failed)
+ {
+ struct info all[20];
+ struct bdata bdata;
+ int j;
+
+ bdata.all = &all[0];
+ bdata.index = 0;
+ bdata.max = 20;
+ bdata.failed = 0;
+
+ for (j = 0; j < 3; ++j)
+ {
+ i = backtrace_pcinfo (state, addrs[j], callback_one,
+ error_callback_one, &bdata);
+ if (i != 0)
+ {
+ fprintf (stderr, ("test3: unexpected return value "
+ "from backtrace_pcinfo %d\n"),
+ i);
+ bdata.failed = 1;
+ }
+ if (!bdata.failed && bdata.index != (size_t) (j + 1))
+ {
+ fprintf (stderr, ("wrong number of calls from backtrace_pcinfo "
+ "got %u expected %d\n"),
+ (unsigned int) bdata.index, j + 1);
+ bdata.failed = 1;
+ }
+ }
+
+ if (bdata.failed)
+ data.failed = 1;
+
+ for (j = 0; j < 1; ++j)
+ {
+ struct symdata symdata;
+
+ symdata.name = NULL;
+ symdata.val = 0;
+ symdata.size = 0;
+ symdata.failed = 0;
+
+ i = backtrace_syminfo (state, addrs[j], callback_three,
+ error_callback_three, &symdata);
+ if (i == 0)
+ {
+ fprintf (stderr, ("test3: [%d]: unexpected return value "
+ "from backtrace_syminfo %d\n"),
+ j, i);
+ symdata.failed = 1;
+ }
+
+ if (!symdata.failed)
+ {
+ const char *expected;
+
+ switch (j)
+ {
+ case 0:
+ expected = "f23";
+ break;
+ default:
+ assert (0);
+ }
+
+ if (symdata.name == NULL)
+ {
+ fprintf (stderr, "test3: [%d]: NULL syminfo name\n", j);
+ symdata.failed = 1;
+ }
+ /* Use strncmp, not strcmp, because GCC might create a
+ clone. */
+ else if (strncmp (symdata.name, expected, strlen (expected)) != 0)
+ {
+ fprintf (stderr, ("test3: [%d]: unexpected syminfo name "
+ "got %s expected %s\n"),
+ j, symdata.name, expected);
+ symdata.failed = 1;
+ }
+ }
+
+ if (symdata.failed)
+ data.failed = 1;
+ }
+ }
+
+ printf ("%s: backtrace_simple noinline\n", data.failed ? "FAIL" : "PASS");
+
+ if (data.failed)
+ ++failures;
+
+ return failures;
+}
+
+static void
+test3 (void)
+{
+ f23 ();
+}
+
+int
+main (int argc ATTRIBUTE_UNUSED, char **argv)
+{
+
+ state = backtrace_create_state (argv[0], BACKTRACE_SUPPORTS_THREADS,
+ error_callback_create, NULL);
+#if BACKTRACE_SUPPORTED
+ test3 ();
+#endif
+
+ return 0;
+}
diff --git a/libbacktrace/internal.h b/libbacktrace/internal.h
index 89b7bf7..48c8218 100644
--- a/libbacktrace/internal.h
+++ b/libbacktrace/internal.h
@@ -108,6 +108,8 @@ extern void backtrace_atomic_store_int (int *, int);
#endif /* !defined (HAVE_SYNC_FUNCTIONS) */
#endif /* !defined (HAVE_ATOMIC_FUNCTIONS) */
+#define MAX_PATH_LEN 4096 /* from linux/limits.h */
+
/* The type of the function that collects file/line information. This
is like backtrace_pcinfo. */
@@ -176,6 +178,26 @@ struct backtrace_view
size_t len;
};
+/* Read the .gnu_debuglink section from elf file and return pointer to
+ * unsigned char with data from that section. If success caller should free the
+ * memory */
+
+extern unsigned char *elf_gnu_debuglink_section (struct backtrace_state *state,
+ int descriptor,
+ backtrace_error_callback error_callback,
+ void *data, int exe,int *
+ gnulink_data_len_out);
+
+
+/* Open debug file which name is placed in gnu_debuglink section.
+ Check the crc32 sum and search file with debug data. On success returns
+ descriptor of that file on fail -1 */
+
+extern int backtrace_open_debugfile (const char *filename,
+ backtrace_error_callback, void *data,
+ int *does_not_exist,
+ struct backtrace_state *state, int exe);
+
/* Create a view of SIZE bytes from DESCRIPTOR at OFFSET. Store the
result in *VIEW. Returns 1 on success, 0 on error. */
extern int backtrace_get_view (struct backtrace_state *state, int descriptor,
diff --git a/libbacktrace/posix.c b/libbacktrace/posix.c
index 5e5571f..f0443ab 100644
--- a/libbacktrace/posix.c
+++ b/libbacktrace/posix.c
@@ -37,9 +37,10 @@ POSSIBILITY OF SUCH DAMAGE. */
#include <sys/stat.h>
#include <fcntl.h>
#include <unistd.h>
-
+#include <string.h>
#include "backtrace.h"
#include "internal.h"
+#include "filenames.h"
#ifndef O_BINARY
#define O_BINARY 0
@@ -53,6 +54,23 @@ POSSIBILITY OF SUCH DAMAGE. */
#define FD_CLOEXEC 1
#endif
+enum type_of_file
+{
+ LINK = 1,
+ REGULAR = 2
+};
+
+enum debug_path
+{
+ CURRENT,
+ CURRENT_DEBUG,
+ USR_LIB_DEBUG,
+ DEBUG_PATH_MAX
+};
+
+static const char *const debug_file_path[DEBUG_PATH_MAX]
+ = {"", ".debug/", "/usr/lib/debug"};
+
/* Open a file for reading. */
int
@@ -98,3 +116,343 @@ backtrace_close (int descriptor, backtrace_error_callback error_callback,
}
return 1;
}
+
+static unsigned long
+getl32 (void *p)
+{
+ char *addr = (char *) p;
+ unsigned long v = 0;
+ v = *((unsigned long *) addr);
+ return v;
+}
+
+/* Function that produce crc32 value */
+
+static unsigned long
+gnu_debuglink_crc32 (unsigned long crc, const unsigned char *buf, size_t len)
+{
+ static const unsigned long crc32_table[256]
+ = {0x00000000, 0x77073096, 0xee0e612c, 0x990951ba, 0x076dc419, 0x706af48f,
+ 0xe963a535, 0x9e6495a3, 0x0edb8832, 0x79dcb8a4, 0xe0d5e91e, 0x97d2d988,
+ 0x09b64c2b, 0x7eb17cbd, 0xe7b82d07, 0x90bf1d91, 0x1db71064, 0x6ab020f2,
+ 0xf3b97148, 0x84be41de, 0x1adad47d, 0x6ddde4eb, 0xf4d4b551, 0x83d385c7,
+ 0x136c9856, 0x646ba8c0, 0xfd62f97a, 0x8a65c9ec, 0x14015c4f, 0x63066cd9,
+ 0xfa0f3d63, 0x8d080df5, 0x3b6e20c8, 0x4c69105e, 0xd56041e4, 0xa2677172,
+ 0x3c03e4d1, 0x4b04d447, 0xd20d85fd, 0xa50ab56b, 0x35b5a8fa, 0x42b2986c,
+ 0xdbbbc9d6, 0xacbcf940, 0x32d86ce3, 0x45df5c75, 0xdcd60dcf, 0xabd13d59,
+ 0x26d930ac, 0x51de003a, 0xc8d75180, 0xbfd06116, 0x21b4f4b5, 0x56b3c423,
+ 0xcfba9599, 0xb8bda50f, 0x2802b89e, 0x5f058808, 0xc60cd9b2, 0xb10be924,
+ 0x2f6f7c87, 0x58684c11, 0xc1611dab, 0xb6662d3d, 0x76dc4190, 0x01db7106,
+ 0x98d220bc, 0xefd5102a, 0x71b18589, 0x06b6b51f, 0x9fbfe4a5, 0xe8b8d433,
+ 0x7807c9a2, 0x0f00f934, 0x9609a88e, 0xe10e9818, 0x7f6a0dbb, 0x086d3d2d,
+ 0x91646c97, 0xe6635c01, 0x6b6b51f4, 0x1c6c6162, 0x856530d8, 0xf262004e,
+ 0x6c0695ed, 0x1b01a57b, 0x8208f4c1, 0xf50fc457, 0x65b0d9c6, 0x12b7e950,
+ 0x8bbeb8ea, 0xfcb9887c, 0x62dd1ddf, 0x15da2d49, 0x8cd37cf3, 0xfbd44c65,
+ 0x4db26158, 0x3ab551ce, 0xa3bc0074, 0xd4bb30e2, 0x4adfa541, 0x3dd895d7,
+ 0xa4d1c46d, 0xd3d6f4fb, 0x4369e96a, 0x346ed9fc, 0xad678846, 0xda60b8d0,
+ 0x44042d73, 0x33031de5, 0xaa0a4c5f, 0xdd0d7cc9, 0x5005713c, 0x270241aa,
+ 0xbe0b1010, 0xc90c2086, 0x5768b525, 0x206f85b3, 0xb966d409, 0xce61e49f,
+ 0x5edef90e, 0x29d9c998, 0xb0d09822, 0xc7d7a8b4, 0x59b33d17, 0x2eb40d81,
+ 0xb7bd5c3b, 0xc0ba6cad, 0xedb88320, 0x9abfb3b6, 0x03b6e20c, 0x74b1d29a,
+ 0xead54739, 0x9dd277af, 0x04db2615, 0x73dc1683, 0xe3630b12, 0x94643b84,
+ 0x0d6d6a3e, 0x7a6a5aa8, 0xe40ecf0b, 0x9309ff9d, 0x0a00ae27, 0x7d079eb1,
+ 0xf00f9344, 0x8708a3d2, 0x1e01f268, 0x6906c2fe, 0xf762575d, 0x806567cb,
+ 0x196c3671, 0x6e6b06e7, 0xfed41b76, 0x89d32be0, 0x10da7a5a, 0x67dd4acc,
+ 0xf9b9df6f, 0x8ebeeff9, 0x17b7be43, 0x60b08ed5, 0xd6d6a3e8, 0xa1d1937e,
+ 0x38d8c2c4, 0x4fdff252, 0xd1bb67f1, 0xa6bc5767, 0x3fb506dd, 0x48b2364b,
+ 0xd80d2bda, 0xaf0a1b4c, 0x36034af6, 0x41047a60, 0xdf60efc3, 0xa867df55,
+ 0x316e8eef, 0x4669be79, 0xcb61b38c, 0xbc66831a, 0x256fd2a0, 0x5268e236,
+ 0xcc0c7795, 0xbb0b4703, 0x220216b9, 0x5505262f, 0xc5ba3bbe, 0xb2bd0b28,
+ 0x2bb45a92, 0x5cb36a04, 0xc2d7ffa7, 0xb5d0cf31, 0x2cd99e8b, 0x5bdeae1d,
+ 0x9b64c2b0, 0xec63f226, 0x756aa39c, 0x026d930a, 0x9c0906a9, 0xeb0e363f,
+ 0x72076785, 0x05005713, 0x95bf4a82, 0xe2b87a14, 0x7bb12bae, 0x0cb61b38,
+ 0x92d28e9b, 0xe5d5be0d, 0x7cdcefb7, 0x0bdbdf21, 0x86d3d2d4, 0xf1d4e242,
+ 0x68ddb3f8, 0x1fda836e, 0x81be16cd, 0xf6b9265b, 0x6fb077e1, 0x18b74777,
+ 0x88085ae6, 0xff0f6a70, 0x66063bca, 0x11010b5c, 0x8f659eff, 0xf862ae69,
+ 0x616bffd3, 0x166ccf45, 0xa00ae278, 0xd70dd2ee, 0x4e048354, 0x3903b3c2,
+ 0xa7672661, 0xd06016f7, 0x4969474d, 0x3e6e77db, 0xaed16a4a, 0xd9d65adc,
+ 0x40df0b66, 0x37d83bf0, 0xa9bcae53, 0xdebb9ec5, 0x47b2cf7f, 0x30b5ffe9,
+ 0xbdbdf21c, 0xcabac28a, 0x53b39330, 0x24b4a3a6, 0xbad03605, 0xcdd70693,
+ 0x54de5729, 0x23d967bf, 0xb3667a2e, 0xc4614ab8, 0x5d681b02, 0x2a6f2b94,
+ 0xb40bbe37, 0xc30c8ea1, 0x5a05df1b, 0x2d02ef8d};
+ const unsigned char *end;
+
+ crc = ~crc & 0xffffffff;
+ for (end = buf + len; buf < end; ++buf)
+ crc = crc32_table[(crc ^ *buf) & 0xff] ^ (crc >> 8);
+ return ~crc & 0xffffffff;
+}
+
+static unsigned long
+get_crc32 (int descriptor)
+{
+ static unsigned char buffer[8 * 1024];
+ unsigned long file_crc = 0;
+ ssize_t count;
+
+ while ((count = read (descriptor, buffer, sizeof (buffer))) > 0)
+ file_crc = gnu_debuglink_crc32 (file_crc, buffer, count);
+
+ return file_crc;
+}
+
+static int
+pathlen (const char *buffer)
+{
+ int len;
+ int count;
+ int full_filename_len;
+
+ count = 0;
+ len = full_filename_len = strlen (buffer);
+ while (len > 1 && !IS_DIR_SEPARATOR (*(buffer + (len - 1))))
+ {
+ ++count;
+ --len;
+ }
+ return len > 1 ? (full_filename_len - count) : -1;
+}
+
+static int
+check_sum (int descriptor, unsigned char *debug_link, unsigned int offset,
+ unsigned int section_size)
+{
+ unsigned long crc32_debug_link;
+ unsigned long crc32_debug_file;
+ offset += 1;
+ offset = (offset + 3) & ~3;
+ if (offset >= section_size)
+ return -1;
+ crc32_debug_link = getl32 (debug_link + offset);
+ crc32_debug_file = get_crc32 (descriptor);
+ return crc32_debug_link == crc32_debug_file;
+}
+
+static int
+get_debug_filename_len (unsigned char *buffer, size_t size)
+{
+ size_t count;
+ unsigned char sign_byte;
+
+ sign_byte = 0x00;
+ count = 0;
+ while (*(buffer + count) != sign_byte && size > count)
+ ++count;
+ return count;
+}
+
+static int
+backtrace_readlink (const char *filename,
+ backtrace_error_callback error_callback, void *data,
+ int *does_not_exist)
+{
+ struct stat link_stat;
+ int file_type;
+ mode_t mode;
+
+ memset (&link_stat, 0, sizeof (struct stat));
+
+ if (lstat (filename, &link_stat) == -1)
+ {
+ if (does_not_exist != NULL && errno == ENOENT)
+ *does_not_exist = 1;
+ else
+ error_callback (data, filename, errno);
+ file_type = -1;
+ }
+
+ mode = link_stat.st_mode & S_IFMT;
+
+ switch (mode)
+ {
+ case S_IFLNK:
+ file_type = LINK;
+ break;
+ case S_IFREG:
+ file_type = REGULAR;
+ break;
+ default:
+ file_type = -1;
+ }
+ return file_type;
+}
+
+/* Open debug file */
+
+int
+backtrace_open_debugfile (const char *filename,
+ backtrace_error_callback error_callback, void *data,
+ int *does_not_exist, struct backtrace_state *state,
+ int exe)
+{
+ ssize_t filename_len;
+ char *buffer;
+ int descriptor;
+ int debug_descriptor;
+ int file_type;
+ unsigned char *debug_link_data;
+ size_t valid_debug_link_data;
+ size_t valid_buffer;
+ size_t valid_descriptor;
+ size_t valid_path_buffer;
+ int debug_filename_len;
+ int debug_link_data_len;
+ int path_len;
+ int debug_does_not_exist;
+ char *path_buffer;
+ int pass;
+ int debug_path_len;
+
+ debug_descriptor = -1;
+ valid_path_buffer = 0;
+ valid_buffer = 0;
+ valid_debug_link_data = 0;
+ debug_link_data_len = 0;
+ file_type = -1;
+
+ descriptor = backtrace_open (filename, error_callback, data, does_not_exist);
+
+ if (descriptor < 0)
+ goto exit;
+
+ valid_descriptor = 1;
+
+ /* check if debug section does exist */
+ debug_link_data
+ = elf_gnu_debuglink_section (state, descriptor, error_callback, data, exe,
+ &debug_link_data_len);
+
+ /* if does not exist, nothing we can do, just go to exit */
+ if (debug_link_data == NULL || debug_link_data_len <= 0)
+ goto exit;
+
+ valid_debug_link_data = 1;
+
+ /* For most files under the /proc directory, stat() does not
+ return the file size in the st_size field from struct stat;
+ instead the field is returned with the value 0.
+ That means we can not use st_size from struct stat to determine the
+ length of the actual filename and should
+ use some max path length for the system to allocate the memory.
+ For this time i defined MAX_PATH_LEN in the internal.h header. */
+
+ buffer = backtrace_alloc(state, MAX_PATH_LEN + 1, error_callback, data);
+
+ if (buffer == NULL)
+ goto exit;
+
+ valid_buffer = 1;
+
+ memset (buffer, 0, MAX_PATH_LEN + 1);
+
+ if (exe)
+ {
+ file_type
+ = backtrace_readlink (filename, error_callback, does_not_exist, data);
+
+ if (file_type == LINK)
+ {
+ /* read the actual filename */
+ filename_len = readlink (filename, buffer, MAX_PATH_LEN);
+ if (filename_len < 0)
+ {
+ error_callback (data, "lstat", errno);
+ goto exit;
+ }
+ }
+ else if (file_type == REGULAR)
+ {
+ filename_len = strlen (filename);
+ memcpy (buffer, filename, filename_len);
+ }
+ else
+ /* other file formats are not supported */
+ goto exit;
+ }
+ else
+ {
+ filename_len = strlen (filename);
+ memcpy (buffer, filename, filename_len);
+ }
+
+ path_len = pathlen (buffer);
+
+ if (path_len < 1)
+ goto exit;
+
+ /* allocate memory for path, we need it because should search in
+ /usr/lib/debug/path/to/executable */
+
+ path_buffer = backtrace_alloc (state, path_len + 1, error_callback, data);
+ if (path_buffer == NULL)
+ goto exit;
+
+ valid_path_buffer = 1;
+
+ memset (path_buffer, 0, path_len + 1);
+ memcpy (path_buffer, buffer, path_len);
+
+ debug_filename_len
+ = get_debug_filename_len (debug_link_data, debug_link_data_len);
+
+ if (debug_filename_len < 1)
+ goto exit;
+
+ for (pass = 0; pass < DEBUG_PATH_MAX; ++pass)
+ {
+ switch (pass)
+ {
+ case CURRENT:
+ {
+ memcpy (buffer + path_len, debug_link_data, debug_filename_len);
+ break;
+ }
+ case CURRENT_DEBUG:
+ {
+ debug_path_len = strlen (debug_file_path[CURRENT_DEBUG]);
+ memcpy (buffer + path_len, debug_file_path[CURRENT_DEBUG],
+ debug_path_len);
+ memcpy (buffer + path_len + debug_path_len, debug_link_data,
+ debug_filename_len);
+ break;
+ }
+ case USR_LIB_DEBUG:
+ {
+ debug_path_len = strlen (debug_file_path[USR_LIB_DEBUG]);
+ memset (buffer, 0, MAX_PATH_LEN + 1);
+ memcpy (buffer, debug_file_path[USR_LIB_DEBUG], debug_path_len);
+ memcpy (buffer + debug_path_len, path_buffer, path_len);
+ memcpy (buffer + debug_path_len + path_len, debug_link_data,
+ debug_filename_len);
+ break;
+ }
+ default:
+ goto exit;
+ }
+
+ debug_descriptor
+ = backtrace_open (buffer, error_callback, data, &debug_does_not_exist);
+
+ if (debug_descriptor > 0)
+ break;
+ }
+
+ /* check the crc32 checksum if it not the same return -1 */
+
+ if (!check_sum (debug_descriptor, debug_link_data, debug_filename_len,
+ debug_link_data_len))
+ debug_descriptor = -1;
+
+exit:
+ if (valid_debug_link_data)
+ backtrace_free (state, debug_link_data, debug_link_data_len, error_callback,
+ data);
+ if (valid_buffer)
+ backtrace_free (state, buffer, MAX_PATH_LEN + 1, error_callback, data);
+ if (valid_path_buffer)
+ backtrace_free (state, path_buffer, path_len + 1, error_callback, data);
+ if (valid_descriptor)
+ backtrace_close (descriptor, error_callback, data);
+ return debug_descriptor;
+}
+
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