Nick Mathewson [Wed, 12 Jul 2017 16:23:33 +0000 (12:23 -0400)]
Always start with one additional worker thread
Now that half the threads are permissive and half are strict, we
need to make sure we have at least two threads, so that we'll
have at least one of each kind.
Nick Mathewson [Wed, 12 Jul 2017 16:18:33 +0000 (12:18 -0400)]
Make the chance for priority inversion thread-specific
Instead of choosing a lower-priority job with a 1/37 chance, have
the chance be 1/37 for half the threads, and 1/2147483647 for the
other half. This way if there are very slow jobs of low priority,
they shouldn't be able to grab all the threads when there is better
work to do.
Nick Mathewson [Wed, 12 Jul 2017 15:47:01 +0000 (11:47 -0400)]
Add support for multi-priority workqueues
Each piece of queued work now has an associated priority value; each
priority goes on a separate queue.
With probability (N-1)/N, the workers will take work from the highest
priority nonempty queue. Otherwise, they'll look for work in a
queue of lower priority. This behavior is meant to prevent
starvation for lower-priority tasks.
It was a mistake to remove these includes: they were needed on
systems where we have openssl 1.1.0 *and* libscrypt, and where we
were validating the one against the other.
Nick Mathewson [Wed, 5 Jul 2017 20:10:45 +0000 (16:10 -0400)]
Only disable -Wfloat-conversion on mingw when it exists.
The 22081 fix disabled -Wfloat-conversion, but -Wfloat-conversion
didn't exist in every relevant mingw; it was added in GCC 4.9.x some
time, if the documentation can be trusted.
Nick Mathewson [Mon, 3 Jul 2017 14:59:31 +0000 (10:59 -0400)]
Fix -Wfloat-conversion C warnings on mingw in clamp_double_to_int64.
We just have to suppress these warnings: Mingw's math.h uses gcc's
__builtin_choose_expr() facility to declare isnan, isfinite, and
signbit. But as implemented in at least some versions of gcc,
__builtin_choose_expr() can generate type warnings even from
branches that are not taken.
Nick Mathewson [Thu, 29 Jun 2017 14:09:06 +0000 (10:09 -0400)]
Adjust unit tests to account for fix to bug 22753.
Our mock network put all the guards on the same IPv4 address, which
doesn't fly when we start applying EnforceDistinctSubnets. So in
this commit, I disable EnforceDistinctSubnets when running the old
guard_restriction_t test.
This commit also adds a regression test for #22753.
Nick Mathewson [Wed, 28 Jun 2017 15:41:50 +0000 (11:41 -0400)]
Consider the exit family when applying guard restrictions.
When the new path selection logic went into place, I accidentally
dropped the code that considered the _family_ of the exit node when
deciding if the guard was usable, and we didn't catch that during
code review.
This patch makes the guard_restriction_t code consider the exit
family as well, and adds some (hopefully redundant) checks for the
case where we lack a node_t for a guard but we have a bridge_info_t
for it.
Fixes bug 22753; bugfix on 0.3.0.1-alpha. Tracked as TROVE-2016-006
and CVE-2017-0377.
Nick Mathewson [Tue, 27 Jun 2017 16:01:46 +0000 (12:01 -0400)]
Mark descriptors as undownloadable when dirserv_add_() rejects them
As of ac2f6b608a18a8595f62384788196d7c3f2875fd in 0.2.1.19-alpha,
Sebastian fixed bug 888 by marking descriptors as "impossible" by
digest if they got rejected during the
router_load_routers_from_string() phase. This fix stopped clients
and relays from downloading the same thing over and over.
But we never made the same change for descriptors rejected during
dirserv_add_{descriptor,extrainfo}. Instead, we tried to notice in
advance that we'd reject them with dirserv_would_reject().
This notice-in-advance check stopped working once we added
key-pinning and didn't make a corresponding key-pinning change to
dirserv_would_reject() [since a routerstatus_t doesn't include an ed25519 key].
So as a fix, let's make the dirserv_add_*() functions mark digests
as undownloadable when they are rejected.
Fixes bug 22349; I am calling this a fix on 0.2.1.19-alpha, though
you could also argue for it being a fix on 0.2.7.2-alpha.
Nick Mathewson [Tue, 27 Jun 2017 14:45:29 +0000 (10:45 -0400)]
Fix an errant memset() into the middle of a struct in cell_pack().
This mistake causes two possible bugs. I believe they are both
harmless IRL.
BUG 1: memory stomping
When we call the memset, we are overwriting two 0 bytes past the end
of packed_cell_t.body. But I think that's harmless in practice,
because the definition of packed_cell_t is:
So we will overwrite either two bytes of inserted_time, or two bytes
of padding, depending on how the platform handles alignment.
If we're overwriting padding, that's safe.
If we are overwriting the inserted_time field, that's also safe: In
every case where we call cell_pack() from connection_or.c, we ignore
the inserted_time field. When we call cell_pack() from relay.c, we
don't set or use inserted_time until right after we have called
cell_pack(). SO I believe we're safe in that case too.
BUG 2: memory exposure
The original reason for this memset was to avoid the possibility of
accidentally leaking uninitialized ram to the network. Now
remember, if wide_circ_ids is false on a connection, we shouldn't
actually be sending more than 512 bytes of packed_cell_t.body, so
these two bytes can only leak to the network if there is another bug
somewhere else in the code that sends more data than is correct.
Fortunately, in relay.c, where we allocate packed_cell_t in
packed_cell_new() , we allocate it with tor_malloc_zero(), which
clears the RAM, right before we call cell_pack. So those
packed_cell_t.body bytes can't leak any information.
That leaves the two calls to cell_pack() in connection_or.c, which
use stack-alocated packed_cell_t instances.
In or_handshake_state_record_cell(), we pass the cell's contents to
crypto_digest_add_bytes(). When we do so, we get the number of
bytes to pass using the same setting of wide_circ_ids as we passed
to cell_pack(). So I believe that's safe.
In connection_or_write_cell_to_buf(), we also use the same setting
of wide_circ_ids in both calls. So I believe that's safe too.
projects / thirdparty / tor.git / log
