Add a changes file.

Fixes bug 16248. Patch from cypherpunks.  Bugfix on 0.2.0.1-alpha.

Reverting this in 0.2.6 only -- we're no backporting
seccomp2-loosening fixes to 0.2.6.

This reverts commit 2ec5e24c.

This is a backport of 19728 and 19690

We still silently ignore
     memwipe(NULL, ch, 0);
and
     memwipe(ptr, ch, 0);  /* for ptr != NULL */

But we now assert on:
     memwipe(NULL, ch, 30);

teor (Tim Wilson-Brown) authored 9 years ago and Nick Mathewson committed 8 years ago

Check size argument to memwipe() for underflow.

Closes bug #18089. Reported by "gk", patch by "teor".
Bugfix on 0.2.3.25 and 0.2.4.6-alpha (#7352),
commit 49dd5ef3 on 7 Nov 2012.

John Brooks authored 9 years ago and Nick Mathewson committed 8 years ago

The length of auth_data from an INTRODUCE2 cell is checked when the
auth_type is recognized (1 or 2), but not for any other non-zero
auth_type. Later, auth_data is assumed to have at least
REND_DESC_COOKIE_LEN bytes, leading to a client-triggered out of bounds
read.

Fixed by checking auth_len before comparing the descriptor cookie
against known clients.

Fixes #15823; bugfix on 0.2.1.6-alpha.

This helps protect against bugs where any part of a buf_t's memory
is passed to a function that expects a NUL-terminated input.

It also closes TROVE-2016-10-001 (aka bug 20384).

("ours" merge because there is a separate 20384 patch for 026)

This helps protect against bugs where any part of a buf_t's memory
is passed to a function that expects a NUL-terminated input.

(ours merge -- there is a separate 0.2.5 patch for 20384.)

This helps protect against bugs where any part of a buf_t's memory
is passed to a function that expects a NUL-terminated input.

In get_token(), we could read one byte past the end of the
region. This is only a big problem in the case where the region
itself is (a) potentially hostile, and (b) not explicitly
nul-terminated.

This patch fixes the underlying bug, and also makes sure that the
one remaining case of not-NUL-terminated potentially hostile data
gets NUL-terminated.

Fix for bug 21018, TROVE-2016-12-002, and CVE-2016-1254