Fix for bug 9543.

Nick Mathewson authored 11 years ago and Roger Dingledine committed 11 years ago

Fortunately, later checks mean that uninitialized data can't get sent
to the network by this bug.  Unfortunately, reading uninitialized heap
*can* (in some cases, with some allocators) cause a crash if you get
unlucky and go off the end of a page.

Found by asn.  Bugfix on 0.2.4.1-alpha.

Now a user who changes only NumEntryGuards will get the behavior she
expects. Fixes bug 9354; bugfix on 0.2.4.8-alpha.

Fixes bug 9337; bugfix on 0.2.4.7-alpha.

When we moved channel_matches_target_addr_for_extend() into a separate
function, its sense was inverted from what one might expect, and we
didn't have a ! in one place where we should have.

Found by skruffy.

Fix for #9254.  Bugfix on 0.2.4.14-alpha.

This is not actually a bug in the Tor code.

 Fix a bug in the voting algorithm that could yield incorrect results
 when a non-naming authority declared too many flags. Fixes bug 9200;
 bugfix on 0.2.0.3-alpha.

Found by coverity scan.

Ticket 9147.

(This caused a crash that was reported as bug 9122, but the underlying
behavior has been wrong for a while.)

Fix on 0.2.3.9-alpha.

Fixes bug 9090; bug not in any released Tor.

This implements "algorithm 1" from my discussion of bug #9072: on OOM,
find the circuits with the longest queues, and kill them.  It's also a
fix for #9063 -- without the side-effects of bug #9072.

The memory bounds aren't perfect here, and you need to be sure to
allow some slack for the rest of Tor's usage.

This isn't a perfect fix; the rest of the solutions I describe on
codeable.

Fixes bug 9002; bugfix on 0.1.1.11-alpha (which introduced guard
nodes), or on 0.0.6pre1 (which introduced hidden services).

This fixes bug 9047 (and some parts of 9031, 8922, 8883 that weren't
fixed in 8822).  Bugfix on 0.2.2.6-alpha.

This is another fix to try to mitigate recurrences of 8031/8822.

This is a reprise of the fix in bdff7e32; 6905c1f6 reintroduced
that bug.  Briefly: windows doesn't seem to like deleting a mapped
file.  I tried adding the PROT_SHARED_DELETE flag to the createfile
all, but that didn't actually fix this issue.  Fortunately, the unit
test I added in 4f4fc63f should
prevent us from making this particular screw-up again.

This patch also tries to limit the crash potential of a failure to
write by a little bit, although it could do a better job of retaining
microdescriptor bodies.

Fix for bug 8822, bugfix on 0.2.4.12-alpha.

This reverts commit 884a0e26.

I'm reverting this because it doesn't actually make the problem go
away.  It appears that instead we need to do unmap-then-replace.

A comment by rransom on #8795 taken together with a comment by doorss
recorded on #2077 suggest that *every* attempt to replace the md cache
will fail on Vista/Win7 if we don't have the FILE_SHARE_DELETE flag
passed to CreateFile, and if we try to replace the file ourselves
before unmapping it.  I'm adding the FILE_SHARE_DELETE, since that's
this simplest fix.  Broken indexers (the favored #2077 hypothesis)
could still cause trouble here, but at least this patch should make us
stop stepping on our own feet.

Likely fix for #2077 and its numerous duplicates. Bugfix on
0.2.2.6-alpha, which first had a microdescriptor cache that would get
replaced before remapping it.

Is it possible that *every* attempt to replace the microdesc cache on
windows 7 is going to fail because of our lack of FILE_SHARE_DELETE
while opening the file?  If so, this test will catch #2077 and let us
know when it's fixed.

There's an assertion failure that can occur if a connection has
optimistic data waiting, and then the connect() call returns 0 on the
first attempt (rather than -1 and EINPROGRESS).  That latter behavior
from connect() appears to be an (Open?)BSDism when dealing with remote
addresses in some cases. (At least, I've only seen it reported with
the BSDs under libevent, even when the address was 127.0.0.1.  And
we've only seen this problem in Tor with OpenBSD.)

Fixes bug 9017; bugfix on 0.2.3.1-alpha, which first introduced
optimistic data. (Although you could also argue that the commented-out
connection_start_writing in 155c9b80 back in 2002 is the real source
of the issue.)

When launching a resolve request on behalf of an AF_UNIX control, omit the address field of the new entry connection.  Fixes bug 8639.

See discussion on #8093

The fix for bug 8117 exposed this bug, and it turns out real-world
applications like Pidgin do care. Bugfix on 0.2.3.2-alpha; fixes bug 8879.