From b3a85a1a8a816f4f6f9c01399c16efe92a86ca06 Mon Sep 17 00:00:00 2001
From: Paul Eggert <eggert@cs.ucla.edu>
Date: Tue, 9 Nov 2021 10:11:42 -0800
Subject: [PATCH] grep: work around PCRE bug
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Problem reported by Carlo Marcelo Arenas Belón (Bug#51710).
* src/pcresearch.c (jit_exec): Don’t attempt to grow the JIT stack
over INT_MAX - 8 * 1024.
---
 src/pcresearch.c | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/src/pcresearch.c b/src/pcresearch.c
index 3bdaee9..09f92c8 100644
--- a/src/pcresearch.c
+++ b/src/pcresearch.c
@@ -72,8 +72,11 @@ jit_exec (struct pcre_comp *pc, char const *subject, int search_bytes,
                          search_offset, options, sub, NSUB);
 
 #if PCRE_STUDY_JIT_COMPILE
+      /* Going over this would trigger an int overflow bug within PCRE.  */
+      int jitstack_max = INT_MAX - 8 * 1024;
+
       if (e == PCRE_ERROR_JIT_STACKLIMIT
-          && 0 < pc->jit_stack_size && pc->jit_stack_size <= INT_MAX / 2)
+          && 0 < pc->jit_stack_size && pc->jit_stack_size <= jitstack_max / 2)
         {
           int old_size = pc->jit_stack_size;
           int new_size = pc->jit_stack_size = old_size * 2;
-- 
1.8.3.1

