In 3.2.x we didn't fix these bugs since servers are trusted and
should send correct commands. In 4.0.x we changed this so we would
fix them when we come across such issues at normal priority (not
consider them security issues). I now took it a step further and
actively checked/looked for these issues and a bunch of them were
found. Almost all are NULL pointer dereferences, with some exceptions.
* S2S: MODE: check conv_param return value (NULL ptr crash)
* S2S: MODE: floodprot: More checks (NULL ptr crash)
* S2S: MODE: OOB write of NULL (write NULL past last element in an array)
* S2S: NICK: old compat fixes (NULL ptr crash)
* S2S: PROTOCTL: Check for double SID=
* S2S: SERVER: require at least 3 parameters (NULL ptr crash)
* S2S: SJOIN: require at least 3 parameters (NULL ptr crash)
* S2S: SJOIN: Fix OOB read (read 1 byte past buffer)
* S2S: TKL: validate set_at and expire_at (NULL ptr crash)
* S2S: TKL: require at least 9 parameters for spamf, not 8 (NULL ptr crash)
* S2S: TKL: ignore invalid spamfilter matching type (remove abort() call)
* S2S: TOPIC: querying for topic is not permitted (NULL ptr crash)
* S2S: UID: require 12 parameters (NULL ptr crash)
* S2S: WATCH: this is not a server command (NULL ptr crash)
* Fix OOB read (1 byte beyond string) for timevals. This was reachable
from config code, TKL (S2S) and /*LINE (Oper). In practice no crash.
* MODE: make code less confusing (effectively no change)
* TRACE: remove strange output in case of 0 lines of output
* Fix unimportant memory leak on boot (#4713, reported by dg)
* Fix small memory leak upon 'DNS i' (oper only command)
* Always work on a copy in clean_ban_mask(). This fixes a bug that could
result in a strlcpy(buf, buf, sizeof(buf)). So, overlapping strings,
which is undefined behavior.
* API change for HOOKTYPE_PRE_INVITE:
(aClient *sptr, aClient *target, aChannel *chptr, int *override)
Modules must now send the error message instead of only returning
HOOK_DENY. Also check for operoverride and set *override=1.
This so modules can send their own error messages instead of the
default message being sent ("channel is +V" - which is not true).
Reported by Gottem (#5023).
set::handshake-delay of 2 seconds by default. This will allow (most)
DNSBL checking to be finished before the user comes online, while
still allowing a smooth user experience.
If your DNS(BL) is slow then you could raise this setting slightly.
You should always use https://www.unrealircd.org/ for stable releases.
In case you wondered what happened with 4.0.15: that version consists
of cherry-picked / backports of the two crash fixes from this 'unreal40'
development branch. The current code simply wasn't ready yet for a
rushed security release.
* The 'ban too broad' checking was broken. This permitted glines such
as 192.168.0.0/1 being set. Now it rejects CIDR of /15 and lower.
To disable this safety measure you can (still) use:
set { options { allow-insane-bans; }; };
Bram Matthys