These errors can occur if we are built on a system with support for
madvise(MADV_NOFORK) but then we are run on a system whose kernel
does not support that flag.
If the error is something that we don't tolerate at all, we now log
it before crashing.
Fixes bug 31696. I am calling this a bugfix on 0.4.1.1-alpha, where
we actually started using the map_anon code.
This is similar to, but not the same as, the fix for #31570.
We used to do this on Windows only, but it appears to affect
multiple platforms when building with certain versions of GCC, and a
common pattern for defining the floating-point classifier functions.
Fixes part of 31687. I'm calling this a bugfux on 31687, when we
started suppressing these warnings on Windows.
These errors can occur if we are built on a system with support for
madvise(MADV_NOFORK) but then we are run on a system whose kernel
does not support that flag.
If the error is something that we don't tolerate at all, we now log
it before crashing.
Fixes bug 31570. I am calling this a bugfix on 0.4.1.1-alpha, where
we actually started using the map_anon code.
Overflowing a signed integer in C is an undefined behaviour.
It is possible to trigger this undefined behaviour in tor_asprintf on
Windows or systems lacking vasprintf.
On these systems, eiter _vscprintf or vsnprintf is called to retrieve
the required amount of bytes to hold the string. These functions can
return INT_MAX. The easiest way to recreate this is the use of a
specially crafted configuration file, e.g. containing the line:
FirewallPorts AAAAA<in total 2147483610 As>
This line triggers the needed tor_asprintf call which eventually
leads to an INT_MAX return value from _vscprintf or vsnprintf.
The needed byte for \0 is added to the result, triggering the
overflow and therefore the undefined behaviour.
Casting the value to size_t before addition fixes the behaviour.
Signed-off-by: Tobias Stoeckmann <tobias@stoeckmann.org>
When we added LD_MESG, we created a conflict with the LD_NO_MOCK
flag. We now need 64 bits for log domains in order to fix this
issue.
Fixes bug 31080; bugfix on 0.4.1.1-alpha.
Fixes assertion failure in tests on NetBSD:
slow/prob_distr/stochastic_log_logistic: [forking] May 25 03:56:58.091 [err] tor_assertion_failed_(): Bug: src/lib/crypt_ops/crypto_rand_fast.c:184: crypto_fast_rng_new_from_seed: Assertion inherit != INHERIT_RES_KEEP failed; aborting. (on Tor 0.4.1.1-alpha-dev 29955f13e5)
May 25 03:56:58.091 [err] Bug: Assertion inherit != INHERIT_RES_KEEP failed in crypto_fast_rng_new_from_seed at src/lib/crypt_ops/crypto_rand_fast.c:184: . (Stack trace not available) (on Tor 0.4.1.1-alpha-dev 29955f13e5)
[Lost connection!]
The ordinary definitions of timeradd() and timersub() contain a
branch. However, in coverage builds, this means that we get spurious
complaints about partially covered basic blocks, in a way that makes
our coverage determinism harder to check.
Ordinarily we skip calling log_fn(LOG_DEBUG,...) if debug logging is
completely disabled. However, in coverage builds, this means that
we get spurious complaints about partially covered basic blocks, in
a way that makes our coverage determinism harder to check.
I don't believe any of these represent a real timing vulnerability
(remote timing against memcmp() on a modern CPU is not easy), but
these are the ones where I believe we should be more careful.
For memeq and friends, "tor_" indicates constant-time and "fast_"
indicates optimized. I'm fine with leaving the constant-time
"safe_mem_is_zero" with its current name, but the "tor_" prefix on
the current optimized version is misleading.
Also, make the tor_digest*_is_zero() uniformly constant-time, and
add a fast_digest*_is_zero() version to use as needed.
A later commit in this branch will fix all the users of
tor_mem_is_zero().
Closes ticket 30309.
Nick Mathewson
David Goulet
teor
Tobias Stoeckmann
Taylor R Campbell