Fix early fail detection

PCRE2Project · Nov 15, 2023 · 2b926df · 2b926df
1 parent b719b47
commit 2b926df
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Showing 2 changed files with 8 additions and 5 deletions.
diff --git a/src/pcre2_jit_compile.c b/src/pcre2_jit_compile.c
@@ -1512,15 +1512,17 @@ do
       case OP_ONCE:
       case OP_BRA:
       case OP_CBRA:
-      end = cc + GET(cc, 1);
-
       prev_fast_forward_allowed = fast_forward_allowed;
       fast_forward_allowed = FALSE;
+
       if (depth >= 4)
         break;
 
-      end = bracketend(cc) - (1 + LINK_SIZE);
-      if (*end != OP_KET || (*cc == OP_CBRA && common->optimized_cbracket[GET2(cc, 1 + LINK_SIZE)] == 0))
+      if (count == 0 && cc[GET(cc, 1)] == OP_ALT)
+        count = 1;
+
+      end = bracketend(cc);
+      if (end[-1 - LINK_SIZE] != OP_KET || (*cc == OP_CBRA && common->optimized_cbracket[GET2(cc, 1 + LINK_SIZE)] == 0))
         break;
 
       count = detect_early_fail(common, cc, private_data_start, depth + 1, count, prev_fast_forward_allowed);
@@ -1530,7 +1532,7 @@ do
 
       if (count < EARLY_FAIL_ENHANCE_MAX)
         {
-        cc = end + (1 + LINK_SIZE);
+        cc = end;
         continue;
         }
       break;

diff --git a/src/pcre2_jit_test.c b/src/pcre2_jit_test.c
@@ -275,6 +275,7 @@ static struct regression_test_case regression_test_cases[] = {
 	{ CM, A, 0, 0, "ab|cd", "CD" },
 	{ CM, A, 0, 0, "a1277|a1377|bX487", "bx487" },
 	{ CM, A, 0, 0, "a1277|a1377|bx487", "bX487" },
+	{ 0, A, 0, 0, "(a|)b*+a", "a" },
 
 	/* Greedy and non-greedy ? operators. */
 	{ MU, A, 0, 0, "(?:a)?a", "laab" },