diff options
Diffstat (limited to 'kdesktop/lock')
| -rw-r--r-- | kdesktop/lock/CMakeLists.txt | 4 | ||||
| -rw-r--r-- | kdesktop/lock/backtrace_symbols.c | 325 | ||||
| -rw-r--r-- | kdesktop/lock/lockprocess.cc | 22 |
3 files changed, 349 insertions, 2 deletions
diff --git a/kdesktop/lock/CMakeLists.txt b/kdesktop/lock/CMakeLists.txt index caa655f59..6694f4315 100644 --- a/kdesktop/lock/CMakeLists.txt +++ b/kdesktop/lock/CMakeLists.txt @@ -32,11 +32,11 @@ set( target kdesktop_lock ) set( ${target}_SRCS lockprocess.cc lockdlg.cc infodlg.cc querydlg.cc sakdlg.cc - securedlg.cc autologout.cc main.cc + securedlg.cc autologout.cc main.cc backtrace_symbols.c ) tde_add_executable( ${target} AUTOMOC SOURCES ${${target}_SRCS} - LINK kdesktopsettings-static dmctl-static kio-shared Xext ${GL_LIBRARY} "${LINKER_IMMEDIATE_BINDING_FLAGS}" + LINK kdesktopsettings-static dmctl-static kio-shared Xext bfd ${GL_LIBRARY} "${LINKER_IMMEDIATE_BINDING_FLAGS}" DESTINATION ${BIN_INSTALL_DIR} ) diff --git a/kdesktop/lock/backtrace_symbols.c b/kdesktop/lock/backtrace_symbols.c new file mode 100644 index 000000000..69aa2d740 --- /dev/null +++ b/kdesktop/lock/backtrace_symbols.c @@ -0,0 +1,325 @@ +/* + A hacky replacement for backtrace_symbols in glibc + + backtrace_symbols in glibc looks up symbols using dladdr which is limited in + the symbols that it sees. libbacktracesymbols opens the executable and shared + libraries using libbfd and will look up backtrace information using the symbol + table and the dwarf line information. + + It may make more sense for this program to use libelf instead of libbfd. + However, I have not investigated that yet. + + Derived from addr2line.c from GNU Binutils by Jeff Muizelaar + + Copyright 2007 Jeff Muizelaar + Copyright 2012 Timothy Pearson +*/ + +/* addr2line.c -- convert addresses to line number and function name + Copyright 1997, 1998, 1999, 2000, 2001, 2002 Free Software Foundation, Inc. + Contributed by Ulrich Lauther <Ulrich.Lauther@mchp.siemens.de> + + This file was part of GNU Binutils. + + This program is free software; you can redistribute it and/or modify + it under the terms of the GNU General Public License as published by + the Free Software Foundation; either version 2, or (at your option) + any later version. + + This program 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 General Public License for more details. + + You should have received a copy of the GNU General Public License + along with this program; if not, write to the Free Software + Foundation, 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */ + +#define fatal(a, b) exit(1) +#define bfd_fatal(a) exit(1) +#define bfd_nonfatal(a) exit(1) +#define list_matching_formats(a) exit(1) + +/* 2 characters for each byte, plus 1 each for 0, x, and NULL */ +#define PTRSTR_LEN (sizeof(void *) * 2 + 3) +#define true 1 +#define false 0 + +#define _GNU_SOURCE +#include <string.h> +#include <stdio.h> +#include <stdlib.h> +#include <execinfo.h> +#include <bfd.h> +#include <libiberty.h> +#include <dlfcn.h> +#include <link.h> +#include <demangle.h> + + +static asymbol **syms; /* Symbol table. */ + +/* 150 isn't special; it's just an arbitrary non-ASCII char value. */ +#define OPTION_DEMANGLER (150) + +static void slurp_symtab(bfd * abfd); +static void find_address_in_section(bfd *abfd, asection *section, void *data); + +/* Read in the symbol table. */ + +static void slurp_symtab(bfd * abfd) +{ + long symcount; + unsigned int size; + + if ((bfd_get_file_flags(abfd) & HAS_SYMS) == 0) + return; + + symcount = (long)bfd_read_minisymbols(abfd, false, (void**) & syms, &size); + if (symcount == 0) + symcount = bfd_read_minisymbols(abfd, true /* dynamic */ , + (void**) & syms, &size); + + if (symcount < 0) + bfd_fatal(bfd_get_filename(abfd)); +} + +/* These global variables are used to pass information between + translate_addresses and find_address_in_section. */ + +static bfd_vma pc; +static const char *filename; +static const char *functionname; +static unsigned int line; +static int found; + +/* Look for an address in a section. This is called via + bfd_map_over_sections. */ + +static void find_address_in_section(bfd *abfd, asection *section, void *data __attribute__ ((__unused__)) ) +{ + bfd_vma vma; + bfd_size_type size; + + if (found) + return; + + if ((bfd_get_section_flags(abfd, section) & SEC_ALLOC) == 0) + return; + + vma = bfd_get_section_vma(abfd, section); + if (pc < vma) + return; + + size = bfd_section_size(abfd, section); + if (pc >= vma + size) + return; + + found = bfd_find_nearest_line(abfd, section, syms, pc - vma, + &filename, &functionname, &line); +} + +/* Read hexadecimal addresses from stdin, translate into + file_name:line_number and optionally function name. */ + +enum { Count, Print }; + +static char** translate_addresses_buf(bfd * abfd, bfd_vma *addr, int naddr) +{ + int naddr_orig = naddr; + char b; + int total = 0; + int state; + char *buf = &b; + int len = 0; + char **ret_buf = NULL; + + /* iterate over the formating twice. + * the first time we count how much space we need + * the second time we do the actual printing */ + for (state=Count; state<=Print; state++) { + if (state == Print) { + ret_buf = (char**)malloc(total + sizeof(char*)*naddr); + buf = (char*)(ret_buf + naddr); + len = total; + } + while (naddr) { + if (state == Print) + ret_buf[naddr-1] = buf; + pc = addr[naddr-1]; + + found = false; + bfd_map_over_sections(abfd, find_address_in_section, + (PTR) NULL); + + if (!found) { + total += snprintf(buf, len, "[0x%llx] \?\?() \?\?:0",(long long unsigned int) addr[naddr-1]) + 1; + } else { + const char *name; + + name = functionname; + if (name == NULL || *name == '\0') + name = "??"; + if (filename != NULL) { + const char *h; + + h = strrchr(filename, '/'); + if (h != NULL) + filename = h + 1; + } + + char* funcname = cplus_demangle(name, DMGL_AUTO); + if (funcname) { + // demangling succeeded + total += snprintf(buf, len, "%s:%u\t%s()", filename ? filename : "??", line, funcname) + 1; + } + else { + // demangling failed + total += snprintf(buf, len, "%s:%u\t%s()", filename ? filename : "??", line, name) + 1; + } + } + if (state == Print) { + /* set buf just past the end of string */ + buf = buf + total + 1; + } + naddr--; + } + naddr = naddr_orig; + } + return ret_buf; +} +/* Process a file. */ + +static char **process_file(const char *file_name, bfd_vma *addr, int naddr) +{ + bfd *abfd; + char **matching; + char **ret_buf; + + abfd = bfd_openr(file_name, NULL); + + if (abfd == NULL) + bfd_fatal(file_name); + + if (bfd_check_format(abfd, bfd_archive)) + fatal("%s: can not get addresses from archive", file_name); + + if (!bfd_check_format_matches(abfd, bfd_object, &matching)) { + bfd_nonfatal(bfd_get_filename(abfd)); + if (bfd_get_error() == + bfd_error_file_ambiguously_recognized) { + list_matching_formats(matching); + free(matching); + } + xexit(1); + } + + slurp_symtab(abfd); + + ret_buf = translate_addresses_buf(abfd, addr, naddr); + + if (syms != NULL) { + free(syms); + syms = NULL; + } + + bfd_close(abfd); + return ret_buf; +} + +#define MAX_DEPTH 16 + +struct file_match { + const char *file; + void *address; + void *base; + void *hdr; +}; + +static int find_matching_file(struct dl_phdr_info *info, + size_t size, void *data) +{ + struct file_match *match = data; + /* This code is modeled from Gfind_proc_info-lsb.c:callback() from libunwind */ + long n; + const ElfW(Phdr) *phdr; + ElfW(Addr) load_base = info->dlpi_addr; + phdr = info->dlpi_phdr; + for (n = info->dlpi_phnum; --n >= 0; phdr++) { + if (phdr->p_type == PT_LOAD) { + ElfW(Addr) vaddr = phdr->p_vaddr + load_base; + if (match->address >= (void*)vaddr && match->address < (void*)(vaddr + phdr->p_memsz)) { + /* we found a match */ + match->file = info->dlpi_name; + match->base = (void*)info->dlpi_addr; + } + } + } + return 0; +} + +char **backtrace_symbols(void *const *buffer, int size) +{ + int stack_depth = size - 1; + int x,y; + /* discard calling function */ + int total = 0; + + char ***locations; + char **final; + char *f_strings; + + locations = (char***)malloc(sizeof(char**) * (stack_depth+1)); + + bfd_init(); + for(x=stack_depth, y=0; x>=0; x--, y++){ + struct file_match match = { .address = buffer[x] }; + char **ret_buf; + bfd_vma addr; + dl_iterate_phdr(find_matching_file, &match); + addr = buffer[x] - match.base; + if (match.file && strlen(match.file)) + ret_buf = process_file(match.file, &addr, 1); + else + ret_buf = process_file("/proc/self/exe", &addr, 1); + locations[x] = ret_buf; + total += strlen(ret_buf[0]) + 1; + } + + /* allocate the array of char* we are going to return and extra space for + * all of the strings */ + final = (char**)malloc(total + (stack_depth + 1) * sizeof(char*)); + /* get a pointer to the extra space */ + f_strings = (char*)(final + stack_depth + 1); + + /* fill in all of strings and pointers */ + for(x=stack_depth; x>=0; x--){ + strcpy(f_strings, locations[x][0]); + free(locations[x]); + final[x] = f_strings; + f_strings += strlen(f_strings) + 1; + } + + free(locations); + + return final; +} + +void +backtrace_symbols_fd(void *const *buffer, int size, int fd) +{ + int j; + char **strings; + + strings = backtrace_symbols(buffer, size); + if (strings == NULL) { + perror("backtrace_symbols"); + exit(EXIT_FAILURE); + } + + for (j = 0; j < size; j++) + printf("%s\n", strings[j]); + + free(strings); +} + diff --git a/kdesktop/lock/lockprocess.cc b/kdesktop/lock/lockprocess.cc index 3c37090a6..70836c26c 100644 --- a/kdesktop/lock/lockprocess.cc +++ b/kdesktop/lock/lockprocess.cc @@ -18,6 +18,8 @@ #include <config.h> +#include <execinfo.h> + #include "lockprocess.h" #include "lockdlg.h" #include "infodlg.h" @@ -129,9 +131,29 @@ static Window gVRootData = 0; static Atom gXA_VROOT; static Atom gXA_SCREENSAVER_VERSION; +void print_trace() +{ + void *array[10]; + size_t size; + char **strings; + size_t i; + + size = backtrace (array, 10); + strings = backtrace_symbols (array, size); + + printf ("[kdesktop_lock] Obtained %zd stack frames.\n\r", size); + + for (i = 0; i < size; i++) { + printf ("[kdesktop_lock] %s\n\r", strings[i]); + } + + free (strings); +} + static void segv_handler(int) { printf("[kdesktop_lock] WARNING: A fatal exception was encountered. Trapping and ignoring it so as not to compromise desktop security...\n\r"); + print_trace(); sleep(1); } |