SctpAssociation: fix memory violation (versatica#943)

* SctpAssociation: fix memory violation

...when sctp debug tag is set, for SCTP_ASSOC_CHANGE notification.

Closes versatica#904

We were taking the 'sn_assoc_change.sac_info' length wrongly, unlike
for the other notifications we are logging.

- usrsctp code where the notification is created:
https://github.com/sctplab/usrsctp/blob/master/usrsctplib/netinet/sctputil.c#L3296

- Example code where this length is retrieved correctly:
https://github.com/sctplab/usrsctp/blob/master/programs/rtcweb.c#L871

* Update CHANGELOG

* normalize CHANGELOG

* be consistent with struct size retrieval

CHANGELOG.md

@@ -11,6 +11,7 @@
 * Fix some libwebrtc issues (PR #944).
 * Tests: Normalize hexadecimal data representation (PR #945).
 * Update NPM deps.
+* `SctpAssociation`: Fix memory violation (PR #943).
 
 
 ### 3.10.12

worker/src/RTC/SctpAssociation.cpp

@@ -772,7 +772,8 @@ namespace RTC
 							static const size_t BufferSize{ 1024 };
 							thread_local static char buffer[BufferSize];
 
-							uint32_t len = notification->sn_header.sn_length;
+							uint32_t len =
+							  notification->sn_assoc_change.sac_length - sizeof(struct sctp_assoc_change);
 
 							for (uint32_t i{ 0 }; i < len; ++i)
 							{
@@ -840,7 +841,8 @@ namespace RTC
 							static const size_t BufferSize{ 1024 };
 							thread_local static char buffer[BufferSize];
 
-							uint32_t len = notification->sn_header.sn_length;
+							uint32_t len =
+							  notification->sn_assoc_change.sac_length - sizeof(struct sctp_assoc_change);
 
 							for (uint32_t i{ 0 }; i < len; ++i)
 							{