diff options
| author | Pauli <pauli@openssl.org> | 2022-07-29 11:00:50 +1000 |
|---|---|---|
| committer | Matt Caswell <matt@openssl.org> | 2022-08-10 12:03:54 +0100 |
| commit | 56d4ff6cd7fc200943197dff65146a8864b7df98 (patch) | |
| tree | 230f8e14dcbf574cb4b8016f350c7e689d029190 /crypto/property | |
| parent | cd854f225bbef9561fad680e2628dfd55be1b141 (diff) | |
property: make cache flushing slight less deterministic
If there is no timer available to seed the stochastic flushing, revert to a
global seed that gets updated each flush.
Reviewed-by: Tomas Mraz <tomas@openssl.org>
Reviewed-by: Matt Caswell <matt@openssl.org>
(Merged from https://github.com/openssl/openssl/pull/18906)
Diffstat (limited to 'crypto/property')
| -rw-r--r-- | crypto/property/property.c | 14 |
1 files changed, 12 insertions, 2 deletions
diff --git a/crypto/property/property.c b/crypto/property/property.c index 672cc35607..d5e35889cc 100644 --- a/crypto/property/property.c +++ b/crypto/property/property.c @@ -15,6 +15,7 @@ #include "internal/core.h" #include "internal/property.h" #include "internal/provider.h" +#include "internal/tsan_assist.h" #include "crypto/ctype.h" #include <openssl/lhash.h> #include <openssl/rand.h> @@ -90,6 +91,7 @@ typedef struct { LHASH_OF(QUERY) *cache; size_t nelem; uint32_t seed; + unsigned char using_global_seed; } IMPL_CACHE_FLUSH; DEFINE_SPARSE_ARRAY_OF(ALGORITHM); @@ -649,13 +651,21 @@ static void impl_cache_flush_one_alg(ossl_uintmax_t idx, ALGORITHM *alg, static void ossl_method_cache_flush_some(OSSL_METHOD_STORE *store) { IMPL_CACHE_FLUSH state; + static TSAN_QUALIFIER uint32_t global_seed = 1; state.nelem = 0; - if ((state.seed = OPENSSL_rdtsc()) == 0) - state.seed = 1; + state.using_global_seed = 0; + if ((state.seed = OPENSSL_rdtsc()) == 0) { + /* If there is no timer available, seed another way */ + state.using_global_seed = 1; + state.seed = tsan_load(&global_seed); + } store->cache_need_flush = 0; ossl_sa_ALGORITHM_doall_arg(store->algs, &impl_cache_flush_one_alg, &state); store->cache_nelem = state.nelem; + /* Without a timer, update the global seed */ + if (state.using_global_seed) + tsan_add(&global_seed, state.seed); } int ossl_method_store_cache_get(OSSL_METHOD_STORE *store, OSSL_PROVIDER *prov, |