diff --git a/core/crypto/sha2/sha2.odin b/core/crypto/sha2/sha2.odin
index 7c7b2da81..9792a4cb8 100644
--- a/core/crypto/sha2/sha2.odin
+++ b/core/crypto/sha2/sha2.odin
@@ -419,8 +419,10 @@ update :: proc(ctx: ^$T, data: []byte) {
     sha2_transf(ctx, shifted_message, block_nb)
 
     rem_len = new_len % CURR_BLOCK_SIZE
-    when T == Sha256_Context      {copy(ctx.block[:], shifted_message[block_nb << 6:rem_len])}
-    else when T == Sha512_Context {copy(ctx.block[:], shifted_message[block_nb << 7:rem_len])}
+    if rem_len > 0 {
+        when T == Sha256_Context      {copy(ctx.block[:], shifted_message[block_nb << 6:rem_len])} 
+        else when T == Sha512_Context {copy(ctx.block[:], shifted_message[block_nb << 7:rem_len])}
+    }
 
     ctx.length = rem_len
     when T == Sha256_Context      {ctx.tot_len += (block_nb + 1) << 6}
diff --git a/core/mem/allocators.odin b/core/mem/allocators.odin
index b8bd9a065..118a7f7e6 100644
--- a/core/mem/allocators.odin
+++ b/core/mem/allocators.odin
@@ -746,6 +746,8 @@ dynamic_pool_reset :: proc(using pool: ^Dynamic_Pool) {
 		free(a, block_allocator)
 	}
 	clear(&out_band_allocations)
+
+	bytes_left = 0 // Make new allocations call `cycle_new_block` again.
 }
 
 dynamic_pool_free_all :: proc(using pool: ^Dynamic_Pool) {
diff --git a/tests/core/crypto/test_core_crypto.odin b/tests/core/crypto/test_core_crypto.odin
index 636632d71..f6b4b10b8 100644
--- a/tests/core/crypto/test_core_crypto.odin
+++ b/tests/core/crypto/test_core_crypto.odin
@@ -14,6 +14,7 @@ package test_core_crypto
 
 import "core:testing"
 import "core:fmt"
+import "core:strings"
 
 import "core:crypto/md2"
 import "core:crypto/md4"
@@ -230,11 +231,14 @@ test_sha224 :: proc(t: ^testing.T) {
 	// Test vectors from
 	// https://csrc.nist.gov/csrc/media/projects/cryptographic-standards-and-guidelines/documents/examples/sha_all.pdf
 	// https://www.di-mgt.com.au/sha_testvectors.html
+	// https://datatracker.ietf.org/doc/html/rfc3874#section-3.3
+    data_1_000_000_a := strings.repeat("a", 1_000_000)
 	test_vectors := [?]TestHash {
 		TestHash{"d14a028c2a3a2bc9476102bb288234c415a2b01f828ea62ac5b3e42f", ""},
 		TestHash{"23097d223405d8228642a477bda255b32aadbce4bda0b3f7e36c9da7", "abc"},
 		TestHash{"75388b16512776cc5dba5da1fd890150b0c6455cb4f58b1952522525", "abcdbcdecdefdefgefghfghighijhijkijkljklmklmnlmnomnopnopq"},
 		TestHash{"c97ca9a559850ce97a04a96def6d99a9e0e0e2ab14e6b8df265fc0b3", "abcdefghbcdefghicdefghijdefghijkefghijklfghijklmghijklmnhijklmnoijklmnopjklmnopqklmnopqrlmnopqrsmnopqrstnopqrstu"},
+		TestHash{"20794655980c91d8bbb4c1ea97618a4bf03f42581948b2ee4ee7ad67", data_1_000_000_a},
 	}
 	for v, _ in test_vectors {
 		computed     := sha2.hash_224(v.str)
diff --git a/tests/vendor/botan/test_vendor_botan.odin b/tests/vendor/botan/test_vendor_botan.odin
index f0ff44ac9..0a93723c8 100644
--- a/tests/vendor/botan/test_vendor_botan.odin
+++ b/tests/vendor/botan/test_vendor_botan.odin
@@ -15,6 +15,7 @@ package test_vendor_botan
 import "core:testing"
 import "core:fmt"
 import "core:os"
+import "core:strings"
 
 import "vendor:botan/md4"
 import "vendor:botan/md5"
@@ -172,11 +173,14 @@ test_sha224 :: proc(t: ^testing.T) {
     // Test vectors from 
     // https://csrc.nist.gov/csrc/media/projects/cryptographic-standards-and-guidelines/documents/examples/sha_all.pdf
     // https://www.di-mgt.com.au/sha_testvectors.html
+    // https://datatracker.ietf.org/doc/html/rfc3874#section-3.3
+    data_1_000_000_a := strings.repeat("a", 1_000_000)
     test_vectors := [?]TestHash {
         TestHash{"d14a028c2a3a2bc9476102bb288234c415a2b01f828ea62ac5b3e42f", ""},
         TestHash{"23097d223405d8228642a477bda255b32aadbce4bda0b3f7e36c9da7", "abc"},
         TestHash{"75388b16512776cc5dba5da1fd890150b0c6455cb4f58b1952522525", "abcdbcdecdefdefgefghfghighijhijkijkljklmklmnlmnomnopnopq"},
         TestHash{"c97ca9a559850ce97a04a96def6d99a9e0e0e2ab14e6b8df265fc0b3", "abcdefghbcdefghicdefghijdefghijkefghijklfghijklmghijklmnhijklmnoijklmnopjklmnopqklmnopqrlmnopqrsmnopqrstnopqrstu"},
+        TestHash{"20794655980c91d8bbb4c1ea97618a4bf03f42581948b2ee4ee7ad67", data_1_000_000_a},
     }
     for v, _ in test_vectors {
         computed     := sha2.hash_224(v.str)