From 78925604e9bcdf4efa734b65e2e6bcc4d21e2e46 Mon Sep 17 00:00:00 2001 From: Damjan Marion Date: Thu, 23 May 2024 13:06:39 +0000 Subject: vlib: stack trace and signal handler improvements - use libunwrap which seems to be industry standard - display traceback on console if running interactive or with syslog disabled (color output unless nocolor specified) - print hexdump of offending code - print library filename for each stack frame Type: improvement Change-Id: I61d3056251b87076be0578ccda300aa311c222ef Signed-off-by: Damjan Marion --- src/vlib/unix/main.c | 114 ++++++++++++++++++++++++++++++++++++++++++--------- 1 file changed, 95 insertions(+), 19 deletions(-) (limited to 'src/vlib') diff --git a/src/vlib/unix/main.c b/src/vlib/unix/main.c index ee28ca8f1aa..11d0cb1160c 100644 --- a/src/vlib/unix/main.c +++ b/src/vlib/unix/main.c @@ -40,6 +40,8 @@ #include #include #include +#include +#include #include #include @@ -96,21 +98,43 @@ static u8 *syslog_msg = 0; int vlib_last_signum = 0; uword vlib_last_faulting_address = 0; +static void +log_one_line () +{ + vec_terminate_c_string (syslog_msg); + if (unix_main.flags & (UNIX_FLAG_INTERACTIVE | UNIX_FLAG_NOSYSLOG)) + fprintf (stderr, "%s\n", syslog_msg); + else + syslog (LOG_ERR | LOG_DAEMON, "%s", syslog_msg); + vec_reset_length (syslog_msg); +} + static void unix_signal_handler (int signum, siginfo_t * si, ucontext_t * uc) { uword fatal = 0; + int color = + (unix_main.flags & (UNIX_FLAG_INTERACTIVE | UNIX_FLAG_NOSYSLOG)) && + (unix_main.flags & UNIX_FLAG_NOCOLOR) == 0; /* These come in handy when looking at core files from optimized images */ vlib_last_signum = signum; vlib_last_faulting_address = (uword) si->si_addr; + if (color) + syslog_msg = format (syslog_msg, ANSI_FG_BR_RED); + syslog_msg = format (syslog_msg, "received signal %U, PC %U", format_signal, signum, format_ucontext_pc, uc); - if (signum == SIGSEGV) + if (signum == SIGSEGV || signum == SIGBUS) syslog_msg = format (syslog_msg, ", faulting address %p", si->si_addr); + if (color) + syslog_msg = format (syslog_msg, ANSI_FG_DEFAULT); + + log_one_line (); + switch (signum) { /* these (caught) signals cause the application to exit */ @@ -120,11 +144,17 @@ unix_signal_handler (int signum, siginfo_t * si, ucontext_t * uc) */ if (unix_main.vlib_main && unix_main.vlib_main->main_loop_exit_set) { - syslog (LOG_ERR | LOG_DAEMON, "received SIGTERM, exiting..."); + syslog_msg = format ( + syslog_msg, "received SIGTERM from PID %d UID %d, exiting...", + si->si_pid, si->si_uid); + log_one_line (); unix_main.vlib_main->main_loop_exit_now = 1; } else - syslog (LOG_ERR | LOG_DAEMON, "IGNORE early SIGTERM..."); + { + syslog_msg = format (syslog_msg, "IGNORE early SIGTERM..."); + log_one_line (); + } break; /* fall through */ case SIGQUIT: @@ -144,26 +174,75 @@ unix_signal_handler (int signum, siginfo_t * si, ucontext_t * uc) break; } - /* Null terminate. */ - vec_add1 (syslog_msg, 0); if (fatal) { - syslog (LOG_ERR | LOG_DAEMON, "%s", syslog_msg); + int skip = 1, index = 0; - /* Address of callers: outer first, inner last. */ - uword callers[15]; - uword n_callers = clib_backtrace (callers, ARRAY_LEN (callers), 0); - int i; - for (i = 0; i < n_callers; i++) + foreach_clib_stack_frame (sf) { - vec_reset_length (syslog_msg); + if (sf->is_signal_frame) + { + int pipefd[2]; + const int n_bytes = 20; + u8 *ip = (void *) sf->ip; + + if (pipe (pipefd) == 0) + { + /* check PC points to valid memory */ + if (write (pipefd[1], ip, n_bytes) == n_bytes) + { + syslog_msg = format (syslog_msg, "Code: "); + if (color) + syslog_msg = format (syslog_msg, ANSI_FG_CYAN); + for (int i = 0; i < n_bytes; i++) + syslog_msg = format (syslog_msg, " %02x", ip[i]); + if (color) + syslog_msg = format (syslog_msg, ANSI_FG_DEFAULT); + } + else + { + syslog_msg = format ( + syslog_msg, "PC contains invalid memory address"); + } + log_one_line (); + foreach_int (i, 0, 1) + close (pipefd[i]); + } + skip = 0; + } + + if (skip) + continue; + + syslog_msg = format (syslog_msg, "#%-2d ", index++); + if (color) + syslog_msg = format (syslog_msg, ANSI_FG_BLUE); + syslog_msg = format (syslog_msg, "0x%016lx", sf->ip); + if (color) + syslog_msg = format (syslog_msg, ANSI_FG_DEFAULT); + + if (sf->name[0]) + { + if (color) + syslog_msg = format (syslog_msg, ANSI_FG_YELLOW); + syslog_msg = + format (syslog_msg, " %s + 0x%x", sf->name, sf->offset); + if (color) + syslog_msg = format (syslog_msg, ANSI_FG_DEFAULT); + } - syslog_msg = - format (syslog_msg, "#%-2d 0x%016lx %U%c", i, callers[i], - format_clib_elf_symbol_with_address, callers[i], 0); + log_one_line (); - syslog (LOG_ERR | LOG_DAEMON, "%s", syslog_msg); + if (sf->file_name) + { + if (color) + syslog_msg = format (syslog_msg, ANSI_FG_GREEN); + syslog_msg = format (syslog_msg, " from %s", sf->file_name); + if (color) + syslog_msg = format (syslog_msg, ANSI_FG_DEFAULT); + log_one_line (); + } } /* have to remove SIGABRT to avoid recursive - os_exit calling abort() */ @@ -175,9 +254,6 @@ unix_signal_handler (int signum, siginfo_t * si, ucontext_t * uc) else os_exit (1); } - else - clib_warning ("%s", syslog_msg); - } static clib_error_t * -- cgit 1.2.3-korg