From: Mark Wielaard <mark@klomp.org>
Date: Tue, 12 Oct 2021 21:25:32 +0000 (+0200)
Subject: vgdb: only queue up to 64 pending signals when waiting for SIGSTOP
X-Git-Tag: VALGRIND_3_18_0~6
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=970820852e542506dd7a4c722fecd73e34363fde;p=thirdparty%2Fvalgrind.git

vgdb: only queue up to 64 pending signals when waiting for SIGSTOP

We should not queue infinite pending signals so we won't run out of
memory when the SIGSTOP never arrives.
---

diff --git a/coregrind/vgdb-invoker-ptrace.c b/coregrind/vgdb-invoker-ptrace.c
index 389748960f..07f3400f95 100644
--- a/coregrind/vgdb-invoker-ptrace.c
+++ b/coregrind/vgdb-invoker-ptrace.c
@@ -300,6 +300,10 @@ Bool waitstopped (pid_t pid, int signal_expected, const char *msg)
 
          // realloc a bigger queue, and store new signal at the end.
          // This is not very efficient but we assume not many sigs are queued.
+         if (signal_queue_sz >= 64) {
+            DEBUG(0, "too many queued signals while waiting for SIGSTOP\n");
+            return False;
+         }
          signal_queue_sz++;
          signal_queue = vrealloc(signal_queue,
                                  sizeof(siginfo_t) * signal_queue_sz);