diff options
Diffstat (limited to 'src/lib/err/backtrace.c')
| -rw-r--r-- | src/lib/err/backtrace.c | 42 |
1 files changed, 31 insertions, 11 deletions
diff --git a/src/lib/err/backtrace.c b/src/lib/err/backtrace.c index 1d1b3bcfa3..8606f42177 100644 --- a/src/lib/err/backtrace.c +++ b/src/lib/err/backtrace.c @@ -68,10 +68,10 @@ // Redundant with util.h, but doing it here so we can avoid that dependency. #define raw_free free -#ifdef USE_BACKTRACE /** Version of Tor to report in backtrace messages. */ static char bt_version[128] = ""; +#ifdef USE_BACKTRACE /** Largest stack depth to try to dump. */ #define MAX_DEPTH 256 /** Static allocation of stack to dump. This is static so we avoid stack @@ -127,7 +127,7 @@ log_backtrace_impl(int severity, int domain, const char *msg, depth = backtrace(cb_buf, MAX_DEPTH); symbols = backtrace_symbols(cb_buf, (int)depth); - logger(severity, domain, "%s. Stack trace:", msg); + logger(severity, domain, "%s: %s. Stack trace:", bt_version, msg); if (!symbols) { /* LCOV_EXCL_START -- we can't provoke this. */ logger(severity, domain, " Unable to generate backtrace."); @@ -193,15 +193,12 @@ dump_stack_symbols_to_error_fds(void) /** Install signal handlers as needed so that when we crash, we produce a * useful stack trace. Return 0 on success, -errno on failure. */ static int -install_bt_handler(const char *software) +install_bt_handler(void) { int trap_signals[] = { SIGSEGV, SIGILL, SIGFPE, SIGBUS, SIGSYS, SIGIO, -1 }; int i, rv=0; - strncpy(bt_version, software, sizeof(bt_version) - 1); - bt_version[sizeof(bt_version) - 1] = 0; - struct sigaction sa; memset(&sa, 0, sizeof(sa)); @@ -243,13 +240,13 @@ void log_backtrace_impl(int severity, int domain, const char *msg, tor_log_fn logger) { - logger(severity, domain, "%s. (Stack trace not available)", msg); + logger(severity, domain, "%s: %s. (Stack trace not available)", + bt_version, msg); } static int -install_bt_handler(const char *software) +install_bt_handler(void) { - (void) software; return 0; } @@ -264,6 +261,14 @@ dump_stack_symbols_to_error_fds(void) } #endif /* defined(NO_BACKTRACE_IMPL) */ +/** Return the tor version used for error messages on crashes. + * Signal-safe: returns a pointer to a static array. */ +const char * +get_tor_backtrace_version(void) +{ + return bt_version; +} + /** Set up code to handle generating error messages on crashes. */ int configure_backtrace_handler(const char *tor_version) @@ -271,10 +276,25 @@ configure_backtrace_handler(const char *tor_version) char version[128] = "Tor\0"; if (tor_version) { - snprintf(version, sizeof(version), "Tor %s", tor_version); + int snp_rv = 0; + /* We can't use strlcat() here, because it is defined in + * string/compat_string.h on some platforms, and string uses torerr. */ + snp_rv = snprintf(version, sizeof(version), "Tor %s", tor_version); + /* It's safe to call raw_assert() here, because raw_assert() does not + * call configure_backtrace_handler(). */ + raw_assert(snp_rv < (int)sizeof(version)); + raw_assert(snp_rv >= 0); } - return install_bt_handler(version); + char *str_rv = NULL; + /* We can't use strlcpy() here, see the note about strlcat() above. */ + str_rv = strncpy(bt_version, version, sizeof(bt_version) - 1); + /* We must terminate bt_version, then raw_assert(), because raw_assert() + * uses bt_version. */ + bt_version[sizeof(bt_version) - 1] = 0; + raw_assert(str_rv == bt_version); + + return install_bt_handler(); } /** Perform end-of-process cleanup for code that generates error messages on |