From 7bbd02d85c0d155bfb30573746d0d28c9e57acf3 Mon Sep 17 00:00:00 2001 From: Eric Wong Date: Sat, 9 Sep 2023 12:01:42 +0000 Subject: [PATCH] xap_helper: clamp workers to USHRT_MAX This allows us to avoid any integer overflow problems while having enough room to grow for some future hardware, though it looks like having hundreds of cores isn't ever going to make it to typical servers nor workstations. --- lib/PublicInbox/xap_helper.h | 9 +++++++-- 1 file changed, 7 insertions(+), 2 deletions(-) diff --git a/lib/PublicInbox/xap_helper.h b/lib/PublicInbox/xap_helper.h index add2fe8ca..7210c9405 100644 --- a/lib/PublicInbox/xap_helper.h +++ b/lib/PublicInbox/xap_helper.h @@ -78,6 +78,7 @@ static FILE *orig_err = stderr; static int orig_err_fd = -1; static void *srch_tree; // tsearch + tdelete + twalk static pid_t *worker_pids; // nr => pid +#define WORKER_MAX USHRT_MAX static unsigned long nworker, nworker_hwm; static int pipefds[2]; @@ -1063,6 +1064,10 @@ static void do_sigchld(void) static void do_sigttin(void) { if (!alive) return; + if (nworker >= WORKER_MAX) { + warnx("workers cannot exceed %zu", (size_t)WORKER_MAX); + return; + } void *p = reallocarray(worker_pids, nworker + 1, sizeof(pid_t)); if (!p) { warn("reallocarray"); @@ -1117,7 +1122,7 @@ int main(int argc, char *argv[]) #ifdef _SC_NPROCESSORS_ONLN long j = sysconf(_SC_NPROCESSORS_ONLN); if (j > 0) - nworker = j > UCHAR_MAX ? UCHAR_MAX : j; + nworker = j > WORKER_MAX ? WORKER_MAX : j; #endif // _SC_NPROCESSORS_ONLN // make warn/warnx/err multi-process friendly: @@ -1130,7 +1135,7 @@ int main(int argc, char *argv[]) switch (c) { case 'j': nworker = strtoul(optarg, &end, 10); - if (*end != 0 || nworker > USHRT_MAX) + if (*end != 0 || nworker > WORKER_MAX) errx(EXIT_FAILURE, "-j %s invalid", optarg); break; case ':': -- 2.47.3