/* abrt-hook-ccpp.cpp - the hook for C/C++ crashing program Copyright (C) 2009 Zdenek Prikryl (zprikryl@redhat.com) Copyright (C) 2009 RedHat inc. 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 of the License, 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, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. */ #include #include "libabrt.h" #ifdef ENABLE_DUMP_TIME_UNWIND #include #include #endif /* ENABLE_DUMP_TIME_UNWIND */ /* I want to use -Werror, but gcc-4.4 throws a curveball: * "warning: ignoring return value of 'ftruncate', declared with attribute warn_unused_result" * and (void) cast is not enough to shut it up! Oh God... */ #define IGNORE_RESULT(func_call) do { if (func_call) /* nothing */; } while (0) /* Custom version of copyfd_xyz, * one which is able to write into two descriptors at once. */ #define CONFIG_FEATURE_COPYBUF_KB 4 static off_t copyfd_sparse(int src_fd, int dst_fd1, int dst_fd2, off_t size2) { off_t total = 0; int last_was_seek = 0; #if CONFIG_FEATURE_COPYBUF_KB <= 4 char buffer[CONFIG_FEATURE_COPYBUF_KB * 1024]; enum { buffer_size = sizeof(buffer) }; #else char *buffer; int buffer_size; /* We want page-aligned buffer, just in case kernel is clever * and can do page-aligned io more efficiently */ buffer = mmap(NULL, CONFIG_FEATURE_COPYBUF_KB * 1024, PROT_READ | PROT_WRITE, MAP_PRIVATE | MAP_ANON, /* ignored: */ -1, 0); buffer_size = CONFIG_FEATURE_COPYBUF_KB * 1024; if (buffer == MAP_FAILED) { buffer = alloca(4 * 1024); buffer_size = 4 * 1024; } #endif while (1) { ssize_t rd = safe_read(src_fd, buffer, buffer_size); if (!rd) { /* eof */ if (last_was_seek) { if (lseek(dst_fd1, -1, SEEK_CUR) < 0 || safe_write(dst_fd1, "", 1) != 1 || (dst_fd2 >= 0 && (lseek(dst_fd2, -1, SEEK_CUR) < 0 || safe_write(dst_fd2, "", 1) != 1 ) ) ) { perror_msg("Write error"); total = -1; goto out; } } /* all done */ goto out; } if (rd < 0) { perror_msg("Read error"); total = -1; goto out; } /* checking sparseness */ ssize_t cnt = rd; while (--cnt >= 0) { if (buffer[cnt] != 0) { /* not sparse */ errno = 0; ssize_t wr1 = full_write(dst_fd1, buffer, rd); ssize_t wr2 = (dst_fd2 >= 0 ? full_write(dst_fd2, buffer, rd) : rd); if (wr1 < rd || wr2 < rd) { perror_msg("Write error"); total = -1; goto out; } last_was_seek = 0; goto adv; } } /* sparse */ xlseek(dst_fd1, rd, SEEK_CUR); if (dst_fd2 >= 0) xlseek(dst_fd2, rd, SEEK_CUR); last_was_seek = 1; adv: total += rd; size2 -= rd; if (size2 < 0) dst_fd2 = -1; //TODO: truncate to 0 or even delete the second file //(currently we delete the file later) } out: #if CONFIG_FEATURE_COPYBUF_KB > 4 if (buffer_size != 4 * 1024) munmap(buffer, buffer_size); #endif return total; } /* Global data */ static char *user_pwd; static struct dump_dir *dd; /* * %s - signal number * %c - ulimit -c value * %p - pid * %u - uid * %g - gid * %t - UNIX time of dump * %e - executable filename * %i - crash thread tid * %P - global pid * %% - output one "%" */ /* Hook must be installed with exactly the same sequence of %c specifiers. * Last one, %h, may be omitted (we can find it out). */ static const char percent_specifiers[] = "%scpugtePi"; static char *core_basename = (char*) "core"; /* * Used for error messages only. * It is either the same as core_basename if it is absolute, * or $PWD/core_basename. */ static char *full_core_basename; static int open_user_core(uid_t uid, uid_t fsuid, pid_t pid, char **percent_values) { errno = 0; if (user_pwd == NULL || chdir(user_pwd) != 0 ) { perror_msg("Can't cd to '%s'", user_pwd); return -1; } struct passwd* pw = getpwuid(uid); gid_t gid = pw ? pw->pw_gid : uid; //log("setting uid: %i gid: %i", uid, gid); xsetegid(gid); xseteuid(fsuid); if (strcmp(core_basename, "core") == 0) { /* Mimic "core.PID" if requested */ char buf[] = "0\n"; int fd = open("/proc/sys/kernel/core_uses_pid", O_RDONLY); if (fd >= 0) { IGNORE_RESULT(read(fd, buf, sizeof(buf))); close(fd); } if (strcmp(buf, "1\n") == 0) { core_basename = xasprintf("%s.%lu", core_basename, (long)pid); } } else { /* Expand old core pattern, put expanded name in core_basename */ core_basename = xstrdup(core_basename); unsigned idx = 0; while (1) { char c = core_basename[idx]; if (!c) break; idx++; if (c != '%') continue; /* We just copied %, look at following char and expand %c */ c = core_basename[idx]; unsigned specifier_num = strchrnul(percent_specifiers, c) - percent_specifiers; if (percent_specifiers[specifier_num] != '\0') /* valid %c (might be %% too) */ { const char *val = "%"; if (specifier_num > 0) /* not %% */ val = percent_values[specifier_num - 1]; //log("c:'%c'", c); //log("val:'%s'", val); /* Replace %c at core_basename[idx] by its value */ idx--; char *old = core_basename; core_basename = xasprintf("%.*s%s%s", idx, core_basename, val, core_basename + idx + 2); //log("pos:'%*s|'", idx, ""); //log("new:'%s'", core_basename); //log("old:'%s'", old); free(old); idx += strlen(val); } /* else: invalid %c, % is already copied verbatim, * next loop iteration will copy c */ } } full_core_basename = core_basename; if (core_basename[0] != '/') core_basename = concat_path_file(user_pwd, core_basename); /* Open (create) compat core file. * man core: * There are various circumstances in which a core dump file * is not produced: * * [skipped obvious ones] * The process does not have permission to write the core file. * ...if a file with the same name exists and is not writable * or is not a regular file (e.g., it is a directory or a symbolic link). * * A file with the same name already exists, but there is more * than one hard link to that file. * * The file system where the core dump file would be created is full; * or has run out of inodes; or is mounted read-only; * or the user has reached their quota for the file system. * * The RLIMIT_CORE or RLIMIT_FSIZE resource limits for the process * are set to zero. * [we check RLIMIT_CORE, but how can we check RLIMIT_FSIZE?] * * The binary being executed by the process does not have * read permission enabled. [how we can check it here?] * * The process is executing a set-user-ID (set-group-ID) program * that is owned by a user (group) other than the real * user (group) ID of the process. [TODO?] * (However, see the description of the prctl(2) PR_SET_DUMPABLE operation, * and the description of the /proc/sys/fs/suid_dumpable file in proc(5).) */ struct stat sb; errno = 0; /* Do not O_TRUNC: if later checks fail, we do not want to have file already modified here */ int user_core_fd = open(core_basename, O_WRONLY | O_CREAT | O_NOFOLLOW, 0600); /* kernel makes 0600 too */ xsetegid(0); xseteuid(0); if (user_core_fd < 0 || fstat(user_core_fd, &sb) != 0 || !S_ISREG(sb.st_mode) || sb.st_nlink != 1 /* kernel internal dumper checks this too: if (inode->i_uid != current->fsuid) , need to mimic? */ ) { if (user_core_fd < 0) perror_msg("Can't open '%s'", full_core_basename); else perror_msg("'%s' is not a regular file with link count 1", full_core_basename); return -1; } if (ftruncate(user_core_fd, 0) != 0) { /* perror first, otherwise unlink may trash errno */ perror_msg("Can't truncate '%s' to size 0", full_core_basename); unlink(core_basename); return -1; } return user_core_fd; } /* Like xopen, but on error, unlocks and deletes dd and user core */ static int create_or_die(const char *filename, int user_core_fd) { int fd = open(filename, O_WRONLY | O_CREAT | O_TRUNC, DEFAULT_DUMP_DIR_MODE); if (fd >= 0) { IGNORE_RESULT(fchown(fd, dd->dd_uid, dd->dd_gid)); return fd; } int sv_errno = errno; if (dd) dd_delete(dd); if (user_core_fd >= 0) { xchdir(user_pwd); unlink(core_basename); } errno = sv_errno; perror_msg_and_die("Can't open '%s'", filename); } static void create_core_backtrace(pid_t tid, const char *executable, int signal_no, const char *dd_path) { #ifdef ENABLE_DUMP_TIME_UNWIND if (g_verbose > 1) sr_debug_parser = true; char *error_message = NULL; bool success = sr_abrt_create_core_stacktrace_from_core_hook(dd_path, tid, executable, signal_no, &error_message); if (!success) { log("Failed to create core_backtrace: %s", error_message); free(error_message); } #endif /* ENABLE_DUMP_TIME_UNWIND */ } static int create_user_core(int user_core_fd, pid_t pid, off_t ulimit_c) { if (user_core_fd >= 0) { off_t core_size = copyfd_size(STDIN_FILENO, user_core_fd, ulimit_c, COPYFD_SPARSE); if (fsync(user_core_fd) != 0 || close(user_core_fd) != 0 || core_size < 0) { /* perror first, otherwise unlink may trash errno */ perror_msg("Error writing '%s'", full_core_basename); xchdir(user_pwd); unlink(core_basename); return 1; } if (ulimit_c == 0 || core_size > ulimit_c) { xchdir(user_pwd); unlink(core_basename); return 1; } log_notice("Saved core dump of pid %lu to %s (%llu bytes)", (long)pid, full_core_basename, (long long)core_size); } return 0; } static int test_configuration(bool setting_SaveFullCore, bool setting_CreateCoreBacktrace) { if (!setting_SaveFullCore && !setting_CreateCoreBacktrace) { fprintf(stderr, "Both SaveFullCore and CreateCoreBacktrace are disabled - " "at least one of them is needed for useful report.\n"); return 1; } return 0; } int save_crashing_binary(pid_t pid, const char *dest_path, uid_t uid, gid_t gid) { char buf[sizeof("/proc/%lu/exe") + sizeof(long)*3]; sprintf(buf, "/proc/%lu/exe", (long)pid); int src_fd_binary = open(buf, O_RDONLY); /* might fail and return -1, it's ok */ if (src_fd_binary < 0) { log_notice("Failed to open an image of crashing binary"); return 0; } int dst_fd = open(dest_path, O_WRONLY | O_CREAT | O_TRUNC, DEFAULT_DUMP_DIR_MODE); if (dst_fd < 0) { log_notice("Failed to create file '%s'", dest_path); close(src_fd_binary); return -1; } IGNORE_RESULT(fchown(dst_fd, uid, gid)); off_t sz = copyfd_eof(src_fd_binary, dst_fd, COPYFD_SPARSE); close(src_fd_binary); return fsync(dst_fd) != 0 || close(dst_fd) != 0 || sz < 0; } int main(int argc, char** argv) { /* Kernel starts us with all fd's closed. * But it's dangerous: * fprintf(stderr) can dump messages into random fds, etc. * Ensure that if any of fd 0,1,2 is closed, we open it to /dev/null. */ int fd = xopen("/dev/null", O_RDWR); while (fd < 2) fd = xdup(fd); if (fd > 2) close(fd); logmode = LOGMODE_JOURNAL; /* Parse abrt.conf */ load_abrt_conf(); /* ... and plugins/CCpp.conf */ bool setting_MakeCompatCore; bool setting_SaveBinaryImage; bool setting_SaveFullCore; bool setting_CreateCoreBacktrace; { map_string_t *settings = new_map_string(); load_abrt_plugin_conf_file("CCpp.conf", settings); const char *value; value = get_map_string_item_or_NULL(settings, "MakeCompatCore"); setting_MakeCompatCore = value && string_to_bool(value); value = get_map_string_item_or_NULL(settings, "SaveBinaryImage"); setting_SaveBinaryImage = value && string_to_bool(value); value = get_map_string_item_or_NULL(settings, "SaveFullCore"); setting_SaveFullCore = value ? string_to_bool(value) : true; value = get_map_string_item_or_NULL(settings, "CreateCoreBacktrace"); setting_CreateCoreBacktrace = value ? string_to_bool(value) : true; value = get_map_string_item_or_NULL(settings, "VerboseLog"); if (value) g_verbose = xatoi_positive(value); free_map_string(settings); } if (argc == 2 && strcmp(argv[1], "--config-test")) return test_configuration(setting_SaveFullCore, setting_CreateCoreBacktrace); if (argc < 8) { /* percent specifier: %s %c %p %u %g %t %e %P %i*/ /* argv: [0] [1] [2] [3] [4] [5] [6] [7] [8] [9]*/ error_msg_and_die("Usage: %s SIGNO CORE_SIZE_LIMIT PID UID GID TIME BINARY_NAME GLOBAL_PID [TID]", argv[0]); } /* Not needed on 2.6.30. * At least 2.6.18 has a bug where * argv[1] = "SIGNO CORE_SIZE_LIMIT PID ..." * argv[2] = "CORE_SIZE_LIMIT PID ..." * and so on. Fixing it: */ if (strchr(argv[1], ' ')) { int i; for (i = 1; argv[i]; i++) { strchrnul(argv[i], ' ')[0] = '\0'; } } errno = 0; const char* signal_str = argv[1]; int signal_no = xatoi_positive(signal_str); off_t ulimit_c = strtoull(argv[2], NULL, 10); if (ulimit_c < 0) /* unlimited? */ { /* set to max possible >0 value */ ulimit_c = ~((off_t)1 << (sizeof(off_t)*8-1)); } const char *pid_str = argv[3]; pid_t local_pid = xatoi_positive(argv[3]); uid_t uid = xatoi_positive(argv[4]); if (errno || local_pid <= 0) { perror_msg_and_die("PID '%s' or limit '%s' is bogus", argv[3], argv[2]); } { char *s = xmalloc_fopen_fgetline_fclose(VAR_RUN"/abrt/saved_core_pattern"); /* If we have a saved pattern and it's not a "|PROG ARGS" thing... */ if (s && s[0] != '|') core_basename = s; else free(s); } const char *global_pid_str = argv[8]; pid_t pid = xatoi_positive(argv[8]); pid_t tid = 0; if (argv[9]) { tid = xatoi_positive(argv[8]); } char path[PATH_MAX]; char *executable = get_executable(pid); if (executable && strstr(executable, "/abrt-hook-ccpp")) { error_msg_and_die("PID %lu is '%s', not dumping it to avoid recursion", (long)pid, executable); } user_pwd = get_cwd(pid); /* may be NULL on error */ log_notice("user_pwd:'%s'", user_pwd); sprintf(path, "/proc/%lu/status", (long)pid); char *proc_pid_status = xmalloc_xopen_read_close(path, /*maxsz:*/ NULL); uid_t fsuid = uid; uid_t tmp_fsuid = get_fsuid(proc_pid_status); if (tmp_fsuid < 0) perror_msg_and_die("Can't parse 'Uid: line' in /proc/%lu/status", (long)pid); int suid_policy = dump_suid_policy(); if (tmp_fsuid != uid) { /* use root for suided apps unless it's explicitly set to UNSAFE */ fsuid = 0; if (suid_policy == DUMP_SUID_UNSAFE) { fsuid = tmp_fsuid; } } /* Open a fd to compat coredump, if requested and is possible */ int user_core_fd = -1; if (setting_MakeCompatCore && ulimit_c != 0) /* note: checks "user_pwd == NULL" inside; updates core_basename */ user_core_fd = open_user_core(uid, fsuid, pid, &argv[1]); if (executable == NULL) { /* readlink on /proc/$PID/exe failed, don't create abrt dump dir */ error_msg("Can't read /proc/%lu/exe link", (long)pid); return create_user_core(user_core_fd, pid, ulimit_c); } const char *signame = NULL; if (!signal_is_fatal(signal_no, &signame)) return create_user_core(user_core_fd, pid, ulimit_c); // not a signal we care about if (!daemon_is_ok()) { /* not an error, exit with exit code 0 */ log("abrtd is not running. If it crashed, " "/proc/sys/kernel/core_pattern contains a stale value, " "consider resetting it to 'core'" ); return create_user_core(user_core_fd, pid, ulimit_c); } if (g_settings_nMaxCrashReportsSize > 0) { /* If free space is less than 1/4 of MaxCrashReportsSize... */ if (low_free_space(g_settings_nMaxCrashReportsSize, g_settings_dump_location)) return create_user_core(user_core_fd, pid, ulimit_c); } /* Check /var/tmp/abrt/last-ccpp marker, do not dump repeated crashes * if they happen too often. Else, write new marker value. */ snprintf(path, sizeof(path), "%s/last-ccpp", g_settings_dump_location); if (check_recent_crash_file(path, executable)) { /* It is a repeating crash */ return create_user_core(user_core_fd, pid, ulimit_c); } const char *last_slash = strrchr(executable, '/'); if (last_slash && strncmp(++last_slash, "abrt", 4) == 0) { /* If abrtd/abrt-foo crashes, we don't want to create a _directory_, * since that can make new copy of abrtd to process it, * and maybe crash again... * Unlike dirs, mere files are ignored by abrtd. */ snprintf(path, sizeof(path), "%s/%s-coredump", g_settings_dump_location, last_slash); int abrt_core_fd = xopen3(path, O_WRONLY | O_CREAT | O_TRUNC, 0600); off_t core_size = copyfd_eof(STDIN_FILENO, abrt_core_fd, COPYFD_SPARSE); if (core_size < 0 || fsync(abrt_core_fd) != 0) { unlink(path); /* copyfd_eof logs the error including errno string, * but it does not log file name */ error_msg_and_die("Error saving '%s'", path); } log_notice("Saved core dump of pid %lu (%s) to %s (%llu bytes)", (long)pid, executable, path, (long long)core_size); return 0; } unsigned path_len = snprintf(path, sizeof(path), "%s/ccpp-%s-%lu.new", g_settings_dump_location, iso_date_string(NULL), (long)pid); if (path_len >= (sizeof(path) - sizeof("/"FILENAME_COREDUMP))) { return create_user_core(user_core_fd, pid, ulimit_c); } /* use fsuid instead of uid, so we don't expose any sensitive * information of suided app in /var/tmp/abrt */ dd = dd_create(path, fsuid, DEFAULT_DUMP_DIR_MODE); if (dd) { char source_filename[sizeof("/proc/%lu/somewhat_long_name") + sizeof(long)*3]; int source_base_ofs = sprintf(source_filename, "/proc/%lu/root", (long)pid); source_base_ofs -= strlen("root"); /* What's wrong on using /proc/[pid]/root every time ?*/ /* It creates os_info_in_root_dir for all crashes. */ char *rootdir = process_has_own_root(pid) ? get_rootdir(pid) : NULL; /* Yes, test 'rootdir' but use 'source_filename' because 'rootdir' can * be '/' for a process with own namespace. 'source_filename' is /proc/[pid]/root. */ dd_create_basic_files(dd, fsuid, (rootdir != NULL) ? source_filename : NULL); char *dest_filename = concat_path_file(dd->dd_dirname, "also_somewhat_longish_name"); char *dest_base = strrchr(dest_filename, '/') + 1; // Disabled for now: /proc/PID/smaps tends to be BIG, // and not much more informative than /proc/PID/maps: //copy_file(source_filename, dest_filename, 0640); //chown(dest_filename, dd->dd_uid, dd->dd_gid); strcpy(source_filename + source_base_ofs, "maps"); strcpy(dest_base, FILENAME_MAPS); copy_file(source_filename, dest_filename, DEFAULT_DUMP_DIR_MODE); IGNORE_RESULT(chown(dest_filename, dd->dd_uid, dd->dd_gid)); strcpy(source_filename + source_base_ofs, "limits"); strcpy(dest_base, FILENAME_LIMITS); copy_file(source_filename, dest_filename, DEFAULT_DUMP_DIR_MODE); IGNORE_RESULT(chown(dest_filename, dd->dd_uid, dd->dd_gid)); strcpy(source_filename + source_base_ofs, "cgroup"); strcpy(dest_base, FILENAME_CGROUP); copy_file(source_filename, dest_filename, DEFAULT_DUMP_DIR_MODE); IGNORE_RESULT(chown(dest_filename, dd->dd_uid, dd->dd_gid)); strcpy(source_filename + source_base_ofs, "mountinfo"); strcpy(dest_base, FILENAME_MOUNTINFO); copy_file(source_filename, dest_filename, DEFAULT_DUMP_DIR_MODE); IGNORE_RESULT(chown(dest_filename, dd->dd_uid, dd->dd_gid)); strcpy(dest_base, FILENAME_OPEN_FDS); strcpy(source_filename + source_base_ofs, "fd"); if (dump_fd_info(dest_filename, source_filename) == 0) IGNORE_RESULT(chown(dest_filename, dd->dd_uid, dd->dd_gid)); strcpy(dest_base, FILENAME_NAMESPACES); if (dump_namespace_diff(dest_filename, 1, pid)) IGNORE_RESULT(chown(dest_filename, dd->dd_uid, dd->dd_gid)); free(dest_filename); char *tmp = NULL; get_env_variable(pid, "container", &tmp); if (tmp != NULL) { dd_save_text(dd, FILENAME_CONTAINER, tmp); free(tmp); tmp = NULL; } get_env_variable(pid, "container_uuid", &tmp); if (tmp != NULL) { dd_save_text(dd, FILENAME_CONTAINER_UUID, tmp); free(tmp); } /* There's no need to compare mount namespaces and search for '/' in * mountifo. Comparison of inodes of '/proc/[pid]/root' and '/' works * fine. If those inodes do not equal each other, we have to verify * that '/proc/[pid]/root' is not a symlink to a chroot. */ const int containerized = (rootdir != NULL && strcmp(rootdir, "/") == 0); if (containerized) { log_debug("Process %d is considered to be containerized", pid); pid_t container_pid; if (get_pid_of_container(pid, &container_pid) == 0) { char *container_cmdline = get_cmdline(container_pid); dd_save_text(dd, FILENAME_CONTAINER_CMDLINE, container_cmdline); free(container_cmdline); } } dd_save_text(dd, FILENAME_ANALYZER, "abrt-ccpp"); dd_save_text(dd, FILENAME_TYPE, "CCpp"); dd_save_text(dd, FILENAME_EXECUTABLE, executable); dd_save_text(dd, FILENAME_PID, pid_str); dd_save_text(dd, FILENAME_GLOBAL_PID, global_pid_str); dd_save_text(dd, FILENAME_PROC_PID_STATUS, proc_pid_status); if (user_pwd) dd_save_text(dd, FILENAME_PWD, user_pwd); if (rootdir) { if (strcmp(rootdir, "/") != 0) dd_save_text(dd, FILENAME_ROOTDIR, rootdir); } free(rootdir); char *reason = xasprintf("%s killed by SIG%s", last_slash, signame ? signame : signal_str); dd_save_text(dd, FILENAME_REASON, reason); free(reason); char *cmdline = get_cmdline(pid); dd_save_text(dd, FILENAME_CMDLINE, cmdline ? : ""); free(cmdline); char *environ = get_environ(pid); dd_save_text(dd, FILENAME_ENVIRON, environ ? : ""); free(environ); char *fips_enabled = xmalloc_fopen_fgetline_fclose("/proc/sys/crypto/fips_enabled"); if (fips_enabled) { if (strcmp(fips_enabled, "0") != 0) dd_save_text(dd, "fips_enabled", fips_enabled); free(fips_enabled); } dd_save_text(dd, FILENAME_ABRT_VERSION, VERSION); if (setting_SaveBinaryImage) { strcpy(path + path_len, "/"FILENAME_BINARY); if (save_crashing_binary(pid, path, dd->dd_uid, dd->dd_gid)) { error_msg("Error saving '%s'", path); goto error_exit; } } off_t core_size = 0; if (setting_SaveFullCore) { strcpy(path + path_len, "/"FILENAME_COREDUMP); int abrt_core_fd = create_or_die(path, user_core_fd); /* We write both coredumps at once. * We can't write user coredump first, since it might be truncated * and thus can't be copied and used as abrt coredump; * and if we write abrt coredump first and then copy it as user one, * then we have a race when process exits but coredump does not exist yet: * $ echo -e '#include\nmain(){raise(SIGSEGV);}' | gcc -o test -x c - * $ rm -f core*; ulimit -c unlimited; ./test; ls -l core* * 21631 Segmentation fault (core dumped) ./test * ls: cannot access core*: No such file or directory <=== BAD */ core_size = copyfd_sparse(STDIN_FILENO, abrt_core_fd, user_core_fd, ulimit_c); if (fsync(abrt_core_fd) != 0 || close(abrt_core_fd) != 0 || core_size < 0) { unlink(path); /* copyfd_sparse logs the error including errno string, * but it does not log file name */ error_msg("Error writing '%s'", path); goto error_exit; } if (user_core_fd >= 0 /* error writing user coredump? */ && (fsync(user_core_fd) != 0 || close(user_core_fd) != 0 /* user coredump is too big? */ || (ulimit_c == 0 /* paranoia */ || core_size > ulimit_c) ) ) { /* nuke it (silently) */ xchdir(user_pwd); unlink(core_basename); } } else { /* User core is created even if WriteFullCore is off. */ create_user_core(user_core_fd, pid, ulimit_c); } /* User core is either written or closed */ user_core_fd = -1; /* * ! No other errors should cause removal of the user core ! */ /* Save JVM crash log if it exists. (JVM's coredump per se * is nearly useless for JVM developers) */ { char *java_log = xasprintf("/tmp/jvm-%lu/hs_error.log", (long)pid); int src_fd = open(java_log, O_RDONLY); free(java_log); /* If we couldn't open the error log in /tmp directory we can try to * read the log from the current directory. It may produce AVC, it * may produce some error log but all these are expected. */ if (src_fd < 0) { java_log = xasprintf("%s/hs_err_pid%lu.log", user_pwd, (long)pid); src_fd = open(java_log, O_RDONLY); free(java_log); } if (src_fd >= 0) { strcpy(path + path_len, "/hs_err.log"); int dst_fd = create_or_die(path, user_core_fd); off_t sz = copyfd_eof(src_fd, dst_fd, COPYFD_SPARSE); if (close(dst_fd) != 0 || sz < 0) { error_msg("Error saving '%s'", path); goto error_exit; } close(src_fd); } } /* Perform crash-time unwind of the guilty thread. */ if (tid > 0 && setting_CreateCoreBacktrace) create_core_backtrace(tid, executable, signal_no, dd->dd_dirname); /* We close dumpdir before we start catering for crash storm case. * Otherwise, delete_dump_dir's from other concurrent * CCpp's won't be able to delete our dump (their delete_dump_dir * will wait for us), and we won't be able to delete their dumps. * Classic deadlock. */ dd_close(dd); dd = NULL; path[path_len] = '\0'; /* path now contains only directory name */ char *newpath = xstrndup(path, path_len - (sizeof(".new")-1)); if (rename(path, newpath) == 0) strcpy(path, newpath); free(newpath); if (core_size > 0) log_notice("Saved core dump of pid %lu (%s) to %s (%llu bytes)", (long)pid, executable, path, (long long)core_size); notify_new_path(path); /* rhbz#539551: "abrt going crazy when crashing process is respawned" */ if (g_settings_nMaxCrashReportsSize > 0) { /* x1.25 and round up to 64m: go a bit up, so that usual in-daemon trimming * kicks in first, and we don't "fight" with it: */ unsigned maxsize = g_settings_nMaxCrashReportsSize + g_settings_nMaxCrashReportsSize / 4; maxsize |= 63; trim_problem_dirs(g_settings_dump_location, maxsize * (double)(1024*1024), path); } return 0; } /* We didn't create abrt dump, but may need to create compat coredump */ return create_user_core(user_core_fd, pid, ulimit_c); error_exit: if (dd) dd_delete(dd); if (user_core_fd >= 0) { xchdir(user_pwd); unlink(core_basename); } xfunc_die(); }