Fix "run for ever" bug for deeply nested [: sequences.

git-svn-id: svn://vcs.exim.org/pcre/code/trunk@1579 2f5784b3-3f2a-0410-8824-cb99058d5e15

4 files changed, 13 insertions, 12 deletions

diff --git a/ChangeLog b/ChangeLog
index 9a34e81..1d4effd 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -88,6 +88,9 @@ Version 8.38 xx-xxx-xxxx
     compiled and could cause reading from uninitialized memory or an incorrect
     error diagnosis.
 
+16. Pathological patterns containing many nested occurrences of [: caused 
+    pcre_compile() to run for a very long time.
+
 
 Version 8.37 28-April-2015
 --------------------------
diff --git a/pcre_compile.c b/pcre_compile.c
index 7912cc6..bc88c76 100644
--- a/pcre_compile.c
+++ b/pcre_compile.c
@@ -3940,19 +3940,12 @@ for (++ptr; *ptr != CHAR_NULL; ptr++)
       (ptr[1] == CHAR_RIGHT_SQUARE_BRACKET ||
        ptr[1] == CHAR_BACKSLASH))
     ptr++;
-  else if (*ptr == CHAR_RIGHT_SQUARE_BRACKET) return FALSE;
-  else
+  else if ((*ptr == CHAR_LEFT_SQUARE_BRACKET && ptr[1] == terminator) ||
+            *ptr == CHAR_RIGHT_SQUARE_BRACKET) return FALSE;
+  else if (*ptr == terminator && ptr[1] == CHAR_RIGHT_SQUARE_BRACKET)
     {
-    if (*ptr == terminator && ptr[1] == CHAR_RIGHT_SQUARE_BRACKET)
-      {
-      *endptr = ptr;
-      return TRUE;
-      }
-    if (*ptr == CHAR_LEFT_SQUARE_BRACKET &&
-         (ptr[1] == CHAR_COLON || ptr[1] == CHAR_DOT ||
-          ptr[1] == CHAR_EQUALS_SIGN) &&
-        check_posix_syntax(ptr, endptr))
-      return FALSE;
+    *endptr = ptr;
+    return TRUE;
     }
   }
 return FALSE;
diff --git a/testdata/testinput2 b/testdata/testinput2
index ddb4b99..92a65df 100644
--- a/testdata/testinput2
+++ b/testdata/testinput2
@@ -4186,4 +4186,6 @@ backtracking verbs. --/
 
 /[[:\\](?'abc')[a:]/
 
+"[[[.\xe8Nq\xffq\xff\xe0\x2|||::Nq\xffq\xff\xe0\x6\x2|||::[[[:[::::::[[[[[::::::::[:[[[:[:::[[[[[[[[[[[[:::::::::::::::::[[.\xe8Nq\xffq\xff\xe0\x2|||::Nq\xffq\xff\xe0\x6\x2|||::[[[:[::::::[[[[[::::::::[:[[[:[:::[[[[[[[[[[[[[[:::E[[[:[:[[:[:::[[:::E[[[:[:[[:'[:::::E[[[:[::::::[[[:[[[[[[[::E[[[:[::::::[[[:[[[[[[[[:[[::[::::[[:::::::[[:[[[[[[[:[[::[:[[:[~"
+
 /-- End of testinput2 --/
diff --git a/testdata/testoutput2 b/testdata/testoutput2
index ab0892b..cda48f5 100644
--- a/testdata/testoutput2
+++ b/testdata/testoutput2
@@ -14504,4 +14504,7 @@ Failed: unmatched parentheses at offset 23
 
 /[[:\\](?'abc')[a:]/
 
+"[[[.\xe8Nq\xffq\xff\xe0\x2|||::Nq\xffq\xff\xe0\x6\x2|||::[[[:[::::::[[[[[::::::::[:[[[:[:::[[[[[[[[[[[[:::::::::::::::::[[.\xe8Nq\xffq\xff\xe0\x2|||::Nq\xffq\xff\xe0\x6\x2|||::[[[:[::::::[[[[[::::::::[:[[[:[:::[[[[[[[[[[[[[[:::E[[[:[:[[:[:::[[:::E[[[:[:[[:'[:::::E[[[:[::::::[[[:[[[[[[[::E[[[:[::::::[[[:[[[[[[[[:[[::[::::[[:::::::[[:[[[[[[[:[[::[:[[:[~"
+Failed: missing terminating ] for character class at offset 353
+
 /-- End of testinput2 --/