wsrep does not identify checksummed events correctly

#2  0x00007ffff4de148a in __assert_fail_base (fmt=0x7ffff4f68750 "%s%s%s:%u: %s%sAssertion `%s' failed.\n%n", assertion=assertiony=0x555559840fa0 "static_cast<uint>(buf - buf_0) == event_len || buf_0[event_len - 1] == 0", file=file@entry=0x55555983d5e0 "/homB/WTs/Fixes/1/TMP/base/sql/log_event.cc", line=line@entry=2628, function=function@entry=0x5555598425e0 <Gtid_log_event::Gtid_log_(unsigned char const*, unsigned int, Format_description_log_event const*)::__PRETTY_FUNCTION__> "Gtid_log_event::Gtid_log_event(cuchar*, uint, const Format_description_log_event*)") at assert.c:92

#3  0x00007ffff4de1502 in __GI___assert_fail (assertion=0x555559840fa0 "static_cast<uint>(buf - buf_0) == event_len || buf_0[even - 1] == 0", file=0x55555983d5e0 "/home3/MDB/WTs/Fixes/1/TMP/base/sql/log_event.cc", line=2628, function=0x5555598425e0 <Gtid_logt::Gtid_log_event(unsigned char const*, unsigned int, Format_description_log_event const*)::__PRETTY_FUNCTION__> "Gtid_log_event:_log_event(const uchar*, uint, const Format_description_log_event*)") at assert.c:101

#4  0x0000555557c098e6 in Gtid_log_event::Gtid_log_event (this=0x617000016288, buf=0x7fffec2efa21 "", event_len=42, description_e0x6140000208c8) at log_event.cc:2627

#5  0x0000555557bfca77 in Log_event::read_log_event (buf=0x7fffec2efa00 "\247I\307`\242\003", event_len=42, error=0x7fffe902f730,=0x6140000208c8, crc_check=1 '\001') at log_event.cc:1141

#6  0x0000555558347691 in wsrep_read_log_event (arg_buf=0x7fffe902f880, arg_buf_len=0x7fffe902f810, description_event=0x614000020

diff --git a/sql/log_event.cc b/sql/log_event.cc

index 9c7c56b1c34..d75fe0c17f3 100644

--- a/sql/log_event.cc

+++ b/sql/log_event.cc

@@ -2564,6 +2564,7 @@ Gtid_log_event::Gtid_log_event(const uchar *buf, uint event_len,

 {

   uint8 header_size= description_event->common_header_len;

   uint8 post_header_len= description_event->post_header_len[GTID_EVENT-1];

+  const uchar *buf_0= buf;

   if (event_len < (uint) header_size + (uint) post_header_len ||

       post_header_len < GTID_HEADER_LEN)

     return;

@@ -2597,6 +2598,8 @@ Gtid_log_event::Gtid_log_event(const uchar *buf, uint event_len,

     memcpy(xid.data, buf, data_length);

     buf+= data_length;

   }

+  DBUG_ASSERT(static_cast<uint>(buf - buf_0) == event_len ||

+              buf_0[event_len - 1] == 0);

 }

#2  0x00007ffff4de148a in __assert_fail_base (fmt=0x7ffff4f68750 "%s%s%s:%u: %s%sAssertion `%s' failed.\n%n", assertion=assertion@entry=0x555559829fa0 "static_cast<uint>(buf - buf_0) == event_len || buf_0[event_len - 1] == 0", file=file@entry=0x5555598266e0 "/home3/MDB/WTs/Fixes/1/TMP/pre-base/sql/log_event.cc", line=line@entry=2602, function=function@entry=0x55555982b5e0 <Gtid_log_event::Gtid_log_event(unsigned char const*, unsigned int, Format_description_log_event const*)::__PRETTY_FUNCTION__> "Gtid_log_event::Gtid_log_event(const uchar*, uint, const Format_description_log_event*)") at assert.c:92

#3  0x00007ffff4de1502 in __GI___assert_fail (assertion=0x555559829fa0 "static_cast<uint>(buf - buf_0) == event_len || buf_0[event_len - 1] == 0", file=0x5555598266e0 "/home3/MDB/WTs/Fixes/1/TMP/pre-base/sql/log_event.cc", line=2602, function=0x55555982b5e0 <Gtid_log_event::Gtid_log_event(unsigned char const*, unsigned int, Format_description_log_event const*)::__PRETTY_FUNCTION__> "Gtid_log_event::Gtid_log_event(const uchar*, uint, const Format_description_log_event*)") at assert.c:101

#4  0x0000555557bf47b8 in Gtid_log_event::Gtid_log_event (this=0x617000016288, buf=0x7fffec1eca20 "", event_len=42, description_event=0x6140000208c8) at log_event.cc:2601

#5  0x0000555557be7cd3 in Log_event::read_log_event (buf=0x7fffec1eca00 "\374N\307`\242\003", event_len=42, error=0x7fffe8f2c730, fdle=0x6140000208c8, crc_check=1 '\001') at log_event.cc:1140

#6  0x0000555558331f0d in wsrep_read_log_event (arg_buf=0x7fffe8f2c880, arg_buf_len=0x7fffe8f2c810, description_event=0x614