Merge #839: Prevent arithmetic on NULL pointer if the scratch space is too small

29a299e373 Run the undefined behaviour sanitizer on Travis (Fabien)
7506e064d7 Prevent arithmetic on NULL pointer if the scratch space is too small (Fabien)

Pull request description:

ACKs for top commit:
  sipa:
    ACK 29a299e373. Reviewed the code changes and verified that building with these sanitizer flags catches the existing error, as well as a signed integer overflow if introduced.
  real-or-random:
    ACK 29a299e373 code inspection
  jonasnick:
    utACK 29a299e373

Tree-SHA512: 4d788f12f3d7b48018e884910adb9b530a05d88f504de83dadeab8a22d75da83c05a1518f7317de5f536c4dd243ea7b347b1eaddb2ca1d804c663e41b85db69d
This commit is contained in:
Jonas Nick
2020-11-04 14:52:56 +00:00
2 changed files with 4 additions and 3 deletions

View File

@@ -31,6 +31,7 @@ env:
- BUILD=distcheck WITH_VALGRIND=no CTIMETEST=no BENCH=no
- CPPFLAGS=-DDETERMINISTIC
- CFLAGS=-O0 CTIMETEST=no
- CFLAGS="-fsanitize=undefined -fno-omit-frame-pointer" LDFLAGS="-fsanitize=undefined -fno-omit-frame-pointer" UBSAN_OPTIONS="print_stacktrace=1:halt_on_error=1" BIGNUM=no ASM=x86_64 ECDH=yes RECOVERY=yes EXPERIMENTAL=yes SCHNORRSIG=yes CTIMETEST=no
- ECMULTGENPRECISION=2
- ECMULTGENPRECISION=8
- RUN_VALGRIND=yes BIGNUM=no ASM=x86_64 ECDH=yes RECOVERY=yes EXPERIMENTAL=yes SCHNORRSIG=yes EXTRAFLAGS="--disable-openssl-tests" BUILD=

View File

@@ -595,11 +595,11 @@ static int secp256k1_ecmult_strauss_batch(const secp256k1_callback* error_callba
scalars = (secp256k1_scalar*)secp256k1_scratch_alloc(error_callback, scratch, n_points * sizeof(secp256k1_scalar));
state.prej = (secp256k1_gej*)secp256k1_scratch_alloc(error_callback, scratch, n_points * ECMULT_TABLE_SIZE(WINDOW_A) * sizeof(secp256k1_gej));
state.zr = (secp256k1_fe*)secp256k1_scratch_alloc(error_callback, scratch, n_points * ECMULT_TABLE_SIZE(WINDOW_A) * sizeof(secp256k1_fe));
state.pre_a = (secp256k1_ge*)secp256k1_scratch_alloc(error_callback, scratch, n_points * 2 * ECMULT_TABLE_SIZE(WINDOW_A) * sizeof(secp256k1_ge));
state.pre_a_lam = state.pre_a + n_points * ECMULT_TABLE_SIZE(WINDOW_A);
state.pre_a = (secp256k1_ge*)secp256k1_scratch_alloc(error_callback, scratch, n_points * ECMULT_TABLE_SIZE(WINDOW_A) * sizeof(secp256k1_ge));
state.pre_a_lam = (secp256k1_ge*)secp256k1_scratch_alloc(error_callback, scratch, n_points * ECMULT_TABLE_SIZE(WINDOW_A) * sizeof(secp256k1_ge));
state.ps = (struct secp256k1_strauss_point_state*)secp256k1_scratch_alloc(error_callback, scratch, n_points * sizeof(struct secp256k1_strauss_point_state));
if (points == NULL || scalars == NULL || state.prej == NULL || state.zr == NULL || state.pre_a == NULL) {
if (points == NULL || scalars == NULL || state.prej == NULL || state.zr == NULL || state.pre_a == NULL || state.pre_a_lam == NULL || state.ps == NULL) {
secp256k1_scratch_apply_checkpoint(error_callback, scratch, scratch_checkpoint);
return 0;
}