Skip to content
New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Jump to bottom

Return NULL early in context_preallocated_create if flags invalid #840

Merged
merged 1 commit into from
Oct 30, 2020
Merged

Return NULL early in context_preallocated_create if flags invalid #840

Changes from all commits
Commits
Show all changes
1 commit
Select commit
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
16 changes: 9 additions & 7 deletions src/secp256k1.c
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -86,6 +86,8 @@ const secp256k1_context *secp256k1_context_no_precomp = &secp256k1_context_no_pr

size_t secp256k1_context_preallocated_size(unsigned int flags) {
size_t ret = ROUND_TO_ALIGN(sizeof(secp256k1_context));
/* A return value of 0 is reserved as an indicator for errors when we call this function internally. */
VERIFY_CHECK(ret != 0);

if (EXPECT((flags & SECP256K1_FLAGS_TYPE_MASK) != SECP256K1_FLAGS_TYPE_CONTEXT, 0)) {
secp256k1_callback_call(&default_illegal_callback,
Expand Down Expand Up @@ -122,21 +124,21 @@ secp256k1_context* secp256k1_context_preallocated_create(void* prealloc, unsigne
if (!secp256k1_selftest()) {
secp256k1_callback_call(&default_error_callback, "self test failed");
}
VERIFY_CHECK(prealloc != NULL);

prealloc_size = secp256k1_context_preallocated_size(flags);
if (prealloc_size == 0) {
return NULL;
}
VERIFY_CHECK(prealloc != NULL);
ret = (secp256k1_context*)manual_alloc(&prealloc, sizeof(secp256k1_context), base, prealloc_size);
ret->illegal_callback = default_illegal_callback;
ret->error_callback = default_error_callback;

if (EXPECT((flags & SECP256K1_FLAGS_TYPE_MASK) != SECP256K1_FLAGS_TYPE_CONTEXT, 0)) {
secp256k1_callback_call(&ret->illegal_callback,
"Invalid flags");
return NULL;
}

secp256k1_ecmult_context_init(&ret->ecmult_ctx);
secp256k1_ecmult_gen_context_init(&ret->ecmult_gen_ctx);

/* Flags have been checked by secp256k1_context_preallocated_size. */
VERIFY_CHECK((flags & SECP256K1_FLAGS_TYPE_MASK) == SECP256K1_FLAGS_TYPE_CONTEXT);
if (flags & SECP256K1_FLAGS_BIT_CONTEXT_SIGN) {
secp256k1_ecmult_gen_context_build(&ret->ecmult_gen_ctx, &prealloc);
}
Expand Down