PATCH: GH #17370, read beyond buffer in grok_inf_nan

Like GH #17367, this was caused by a failure to check that we aren't at
the end of the buffer after advancing the ptr to it.

(cherry picked from commit 9f16475)

t/re/pat.t

@@ -25,7 +25,7 @@ BEGIN {
 skip_all('no re module') unless defined &DynaLoader::boot_DynaLoader;
 skip_all_without_unicode_tables();
 
-plan tests => 866;  # Update this when adding/deleting tests.
+plan tests => 867;  # Update this when adding/deleting tests.
 
 run_tests() unless caller;
 
@@ -2009,6 +2009,9 @@ CODE
     {   # [perl #133871], ASAN/valgrind out-of-bounds access
         fresh_perl_like('qr/\p{nv:NAnq}/', qr/Can't find Unicode property definition/, {}, "GH #17367");
     }
+    {   # GH #17370, ASAN/valgrind out-of-bounds access
+        fresh_perl_like('qr/\p{nv:qnan}/', qr/Can't find Unicode property definition/, {}, "GH #17370");
+    }
 
     {   # [perl #133921], segfault
         fresh_perl_is('qr0||ß+p00000F00000ù\Q00000ÿ00000x00000x0c0e0\Qx0\Qx0\x{0c!}\;\;î0\xÿÿÿþù\Q`\Qx`
{0c!}
e;ù\ò`\Qm`\x{0c!}\;\;îçÿ ç!F/;îçÿù\Q
xÿÿÿÿù`x{0c!}
e;ù\Q`\Qx`\x{c!}\;\;îç!}\;îçÿù\Q‡ \xÿÿÿÿ>=\Qx`\Qx`ù\ò`\Qx`\x{0c!};\;îçÿ Fn0t0c €
d;t ù ç€!00000000000000000000000m/0000000000000000000000000000000m/\x{){} )|i', "", {}, "[perl #133921]");