diff --git a/src/libsodium/crypto_aead/aes256gcm/aesni/aead_aes256gcm_aesni.c b/src/libsodium/crypto_aead/aes256gcm/aesni/aead_aes256gcm_aesni.c
index babf4f4b..842d0649 100644
--- a/src/libsodium/crypto_aead/aes256gcm/aesni/aead_aes256gcm_aesni.c
+++ b/src/libsodium/crypto_aead/aes256gcm/aesni/aead_aes256gcm_aesni.c
@@ -648,8 +648,7 @@ crypto_aead_aes256gcm_encrypt_afternm(unsigned char *c, unsigned long long *clen
 }
 
 int
-crypto_aead_aes256gcm_decrypt_detached_afternm(unsigned char *m, unsigned long long *mlen_p,
-                                               unsigned char *nsec,
+crypto_aead_aes256gcm_decrypt_detached_afternm(unsigned char *m, unsigned char *nsec,
                                                const unsigned char *c, unsigned long long clen,
                                                const unsigned char *mac,
                                                const unsigned char *ad, unsigned long long adlen,
@@ -674,9 +673,6 @@ crypto_aead_aes256gcm_decrypt_detached_afternm(unsigned char *m, unsigned long l
     if (clen > 16ULL * (1ULL << 32)) {
         abort(); /* LCOV_EXCL_LINE */
     }
-    if (mlen_p != NULL) {
-        *mlen_p = 0U;
-    }
     mlen = clen;
 
     memcpy(&n2[0], npub, 3 * 4);
@@ -799,9 +795,6 @@ crypto_aead_aes256gcm_decrypt_detached_afternm(unsigned char *m, unsigned long l
     LOOPDRND128;
     LOOPDRMD128;
 
-    if (mlen_p != NULL) {
-        *mlen_p = mlen;
-    }
     return 0;
 }
 
@@ -813,14 +806,22 @@ crypto_aead_aes256gcm_decrypt_afternm(unsigned char *m, unsigned long long *mlen
                                       const unsigned char *npub,
                                       const crypto_aead_aes256gcm_state *ctx_)
 {
-    if (clen < 16) {
-        return -1;
+    unsigned long long mlen = 0ULL;
+    int                ret = -1;
+
+    if (clen >= crypto_aead_aes256gcm_ABYTES) {
+        ret = crypto_aead_aes256gcm_decrypt_detached_afternm
+            (m, nsec, c, clen - crypto_aead_aes256gcm_ABYTES,
+             c + clen - crypto_aead_aes256gcm_ABYTES,
+             ad, adlen, npub, ctx_);
     }
-    return crypto_aead_aes256gcm_decrypt_detached_afternm(m, mlen_p, nsec,
-                                                          c, clen - crypto_aead_aes256gcm_ABYTES,
-                                                          c + clen - crypto_aead_aes256gcm_ABYTES,
-                                                          ad, adlen,
-                                                          npub, ctx_);
+    if (mlen_p != NULL) {
+        if (ret == 0) {
+            mlen = clen - crypto_aead_aes256gcm_ABYTES;
+        }
+        *mlen_p = mlen;
+    }
+    return ret;
 }
 
 int
@@ -866,7 +867,6 @@ crypto_aead_aes256gcm_encrypt(unsigned char *c,
 
 int
 crypto_aead_aes256gcm_decrypt_detached(unsigned char *m,
-                                       unsigned long long *mlen_p,
                                        unsigned char *nsec,
                                        const unsigned char *c,
                                        unsigned long long clen,
@@ -881,7 +881,7 @@ crypto_aead_aes256gcm_decrypt_detached(unsigned char *m,
     crypto_aead_aes256gcm_beforenm(&ctx, k);
 
     return crypto_aead_aes256gcm_decrypt_detached_afternm
-        (m, mlen_p, nsec, c, clen, mac, ad, adlen, npub,
+        (m, nsec, c, clen, mac, ad, adlen, npub,
             (const crypto_aead_aes256gcm_state *) &ctx);
 }
 
@@ -902,7 +902,7 @@ crypto_aead_aes256gcm_decrypt(unsigned char *m,
 
     return crypto_aead_aes256gcm_decrypt_afternm
         (m, mlen_p, nsec, c, clen, ad, adlen, npub,
-            (const crypto_aead_aes256gcm_state *) &ctx);
+         (const crypto_aead_aes256gcm_state *) &ctx);
 }
 
 int
@@ -942,7 +942,6 @@ crypto_aead_aes256gcm_encrypt(unsigned char *c, unsigned long long *clen_p,
 
 int
 crypto_aead_aes256gcm_decrypt_detached(unsigned char *m,
-                                       unsigned long long *mlen_p,
                                        unsigned char *nsec,
                                        const unsigned char *c,
                                        unsigned long long clen,
@@ -1000,8 +999,7 @@ crypto_aead_aes256gcm_encrypt_afternm(unsigned char *c, unsigned long long *clen
 }
 
 int
-crypto_aead_aes256gcm_decrypt_detached_afternm(unsigned char *m, unsigned long long *mlen_p,
-                                               unsigned char *nsec,
+crypto_aead_aes256gcm_decrypt_detached_afternm(unsigned char *m, unsigned char *nsec,
                                                const unsigned char *c, unsigned long long clen,
                                                const unsigned char *mac,
                                                const unsigned char *ad, unsigned long long adlen,
diff --git a/src/libsodium/crypto_aead/chacha20poly1305/sodium/aead_chacha20poly1305.c b/src/libsodium/crypto_aead/chacha20poly1305/sodium/aead_chacha20poly1305.c
index 215e80de..0318bfb2 100644
--- a/src/libsodium/crypto_aead/chacha20poly1305/sodium/aead_chacha20poly1305.c
+++ b/src/libsodium/crypto_aead/chacha20poly1305/sodium/aead_chacha20poly1305.c
@@ -178,7 +178,6 @@ crypto_aead_chacha20poly1305_ietf_encrypt(unsigned char *c,
 
 int
 crypto_aead_chacha20poly1305_decrypt_detached(unsigned char *m,
-                                              unsigned long long *mlen_p,
                                               unsigned char *nsec,
                                               const unsigned char *c,
                                               unsigned long long clen,
@@ -196,9 +195,6 @@ crypto_aead_chacha20poly1305_decrypt_detached(unsigned char *m,
     int                               ret;
 
     (void) nsec;
-    if (mlen_p != NULL) {
-        *mlen_p = 0ULL;
-    }
     crypto_stream_chacha20(block0, sizeof block0, npub, k);
     crypto_onetimeauth_poly1305_init(&state, block0);
     sodium_memzero(block0, sizeof block0);
@@ -223,9 +219,7 @@ crypto_aead_chacha20poly1305_decrypt_detached(unsigned char *m,
         return -1;
     }
     crypto_stream_chacha20_xor_ic(m, c, mlen, npub, 1U, k);
-    if (mlen_p != NULL) {
-        *mlen_p = mlen;
-    }
+
     return 0;
 }
 
@@ -240,20 +234,27 @@ crypto_aead_chacha20poly1305_decrypt(unsigned char *m,
                                      const unsigned char *npub,
                                      const unsigned char *k)
 {
-    if (clen < crypto_aead_chacha20poly1305_ABYTES) {
-        return -1;
+    unsigned long long mlen = 0ULL;
+    int                ret = -1;
+
+    if (clen >= crypto_aead_chacha20poly1305_ABYTES) {
+        ret = crypto_aead_chacha20poly1305_decrypt_detached
+            (m, nsec,
+             c, clen - crypto_aead_chacha20poly1305_ABYTES,
+             c + clen - crypto_aead_chacha20poly1305_ABYTES,
+             ad, adlen, npub, k);
     }
-    return crypto_aead_chacha20poly1305_decrypt_detached
-        (m, mlen_p, nsec,
-         c, clen - crypto_aead_chacha20poly1305_ABYTES,
-         c + clen - crypto_aead_chacha20poly1305_ABYTES,
-         ad, adlen,
-         npub, k);
+    if (mlen_p != NULL) {
+        if (ret == 0) {
+            mlen = clen - crypto_aead_chacha20poly1305_ABYTES;
+        }
+        *mlen_p = mlen;
+    }
+    return ret;
 }
 
 int
 crypto_aead_chacha20poly1305_ietf_decrypt_detached(unsigned char *m,
-                                                   unsigned long long *mlen_p,
                                                    unsigned char *nsec,
                                                    const unsigned char *c,
                                                    unsigned long long clen,
@@ -271,9 +272,6 @@ crypto_aead_chacha20poly1305_ietf_decrypt_detached(unsigned char *m,
     int                               ret;
 
     (void) nsec;
-    if (mlen_p != NULL) {
-        *mlen_p = 0ULL;
-    }
     crypto_stream_chacha20_ietf(block0, sizeof block0, npub, k);
     crypto_onetimeauth_poly1305_init(&state, block0);
     sodium_memzero(block0, sizeof block0);
@@ -302,9 +300,7 @@ crypto_aead_chacha20poly1305_ietf_decrypt_detached(unsigned char *m,
         return -1;
     }
     crypto_stream_chacha20_ietf_xor_ic(m, c, mlen, npub, 1U, k);
-    if (mlen_p != NULL) {
-        *mlen_p = mlen;
-    }
+
     return 0;
 }
 
@@ -319,15 +315,23 @@ crypto_aead_chacha20poly1305_ietf_decrypt(unsigned char *m,
                                           const unsigned char *npub,
                                           const unsigned char *k)
 {
-    if (clen < crypto_aead_chacha20poly1305_ietf_ABYTES) {
-        return -1;
+    unsigned long long mlen = 0ULL;
+    int                ret = -1;
+
+    if (clen >= crypto_aead_chacha20poly1305_ietf_ABYTES) {
+        ret = crypto_aead_chacha20poly1305_ietf_decrypt_detached
+            (m, nsec,
+             c, clen - crypto_aead_chacha20poly1305_ietf_ABYTES,
+             c + clen - crypto_aead_chacha20poly1305_ietf_ABYTES,
+             ad, adlen, npub, k);
     }
-    return crypto_aead_chacha20poly1305_ietf_decrypt_detached
-        (m, mlen_p, nsec,
-         c, clen - crypto_aead_chacha20poly1305_ietf_ABYTES,
-         c + clen - crypto_aead_chacha20poly1305_ietf_ABYTES,
-         ad, adlen,
-         npub, k);
+    if (mlen_p != NULL) {
+        if (ret == 0) {
+            mlen = clen - crypto_aead_chacha20poly1305_ietf_ABYTES;
+        }
+        *mlen_p = mlen;
+    }
+    return ret;
 }
 
 size_t
diff --git a/src/libsodium/include/sodium/crypto_aead_aes256gcm.h b/src/libsodium/include/sodium/crypto_aead_aes256gcm.h
index 6651c3c2..d7be4848 100644
--- a/src/libsodium/include/sodium/crypto_aead_aes256gcm.h
+++ b/src/libsodium/include/sodium/crypto_aead_aes256gcm.h
@@ -71,7 +71,6 @@ int crypto_aead_aes256gcm_encrypt_detached(unsigned char *c,
 
 SODIUM_EXPORT
 int crypto_aead_aes256gcm_decrypt_detached(unsigned char *m,
-                                           unsigned long long *mlen_p,
                                            unsigned char *nsec,
                                            const unsigned char *c,
                                            unsigned long long clen,
@@ -125,7 +124,6 @@ int crypto_aead_aes256gcm_encrypt_detached_afternm(unsigned char *c,
 
 SODIUM_EXPORT
 int crypto_aead_aes256gcm_decrypt_detached_afternm(unsigned char *m,
-                                                   unsigned long long *mlen_p,
                                                    unsigned char *nsec,
                                                    const unsigned char *c,
                                                    unsigned long long clen,
diff --git a/src/libsodium/include/sodium/crypto_aead_chacha20poly1305.h b/src/libsodium/include/sodium/crypto_aead_chacha20poly1305.h
index 48378ba6..8ee5e42d 100644
--- a/src/libsodium/include/sodium/crypto_aead_chacha20poly1305.h
+++ b/src/libsodium/include/sodium/crypto_aead_chacha20poly1305.h
@@ -67,7 +67,6 @@ int crypto_aead_chacha20poly1305_ietf_encrypt_detached(unsigned char *c,
 
 SODIUM_EXPORT
 int crypto_aead_chacha20poly1305_ietf_decrypt_detached(unsigned char *m,
-                                                       unsigned long long *mlen_p,
                                                        unsigned char *nsec,
                                                        const unsigned char *c,
                                                        unsigned long long clen,
@@ -133,7 +132,6 @@ int crypto_aead_chacha20poly1305_encrypt_detached(unsigned char *c,
 
 SODIUM_EXPORT
 int crypto_aead_chacha20poly1305_decrypt_detached(unsigned char *m,
-                                                  unsigned long long *mlen_p,
                                                   unsigned char *nsec,
                                                   const unsigned char *c,
                                                   unsigned long long clen,
diff --git a/test/default/aead_aes256gcm.c b/test/default/aead_aes256gcm.c
index 07fadf47..cd6760b5 100644
--- a/test/default/aead_aes256gcm.c
+++ b/test/default/aead_aes256gcm.c
@@ -3167,6 +3167,7 @@ tv(void)
         }
 
         decrypted = (unsigned char *) sodium_malloc(message_len);
+        found_message_len = 1;
         if (crypto_aead_aes256gcm_decrypt(decrypted, &found_message_len,
                                           NULL, ciphertext,
                                           randombytes_uniform(ciphertext_len),
@@ -3174,6 +3175,9 @@ tv(void)
             printf("Verification of test vector #%u after truncation succeeded\n",
                    (unsigned int) i);
         }
+        if (found_message_len != 0) {
+            printf("Message length should have been set to zero after a failure\n");
+        }
         if (crypto_aead_aes256gcm_decrypt(decrypted, &found_message_len,
                                           NULL, ciphertext,
                                           randombytes_uniform(crypto_aead_aes256gcm_ABYTES),
@@ -3190,15 +3194,13 @@ tv(void)
         if (memcmp(decrypted, message, message_len) != 0) {
             printf("Incorrect decryption of test vector #%u\n", (unsigned int) i);
         }
-
         memset(decrypted, 0xd0, message_len);
-        if (crypto_aead_aes256gcm_decrypt_detached(decrypted, &found_message_len,
+        if (crypto_aead_aes256gcm_decrypt_detached(decrypted,
                                                    NULL, detached_ciphertext,
                                                    detached_ciphertext_len,
                                                    mac, ad, ad_len, nonce, key) != 0) {
             printf("Detached verification of test vector #%u failed\n", (unsigned int) i);
         }
-        assert((size_t) found_message_len == message_len);
         if (memcmp(decrypted, message, message_len) != 0) {
             printf("Incorrect decryption of test vector #%u\n", (unsigned int) i);
         }
diff --git a/test/default/aead_chacha20poly1305.c b/test/default/aead_chacha20poly1305.c
index 568751b8..f8e14e11 100644
--- a/test/default/aead_chacha20poly1305.c
+++ b/test/default/aead_chacha20poly1305.c
@@ -66,15 +66,12 @@ tv(void)
         printf("m != m2\n");
     }
     memset(m2, 0, m2len);
-    if (crypto_aead_chacha20poly1305_decrypt_detached(m2, &m2len, NULL,
+    if (crypto_aead_chacha20poly1305_decrypt_detached(m2, NULL,
                                                       c, MLEN, mac,
                                                       ad, ADLEN,
                                                       nonce, firstkey) != 0) {
         printf("crypto_aead_chacha20poly1305_decrypt_detached() failed\n");
     }
-    if (m2len != MLEN) {
-        printf("detached m2len is not properly set\n");
-    }
     if (memcmp(m, m2, MLEN) != 0) {
         printf("detached m != m2\n");
     }
@@ -112,18 +109,25 @@ tv(void)
     if (memcmp(m, m2, MLEN) != 0) {
         printf("m != m2 (adlen=0)\n");
     }
-
+    m2len = 1;
     if (crypto_aead_chacha20poly1305_decrypt(
             m2, &m2len, NULL, c, crypto_aead_chacha20poly1305_ABYTES / 2, NULL,
             0U, nonce, firstkey) != -1) {
         printf("crypto_aead_chacha20poly1305_decrypt() worked with a short "
                "ciphertext\n");
     }
+    if (m2len != 0) {
+        printf("Message length should have been set to zero after a failure\n");
+    }
+    m2len = 1;
     if (crypto_aead_chacha20poly1305_decrypt(m2, &m2len, NULL, c, 0U, NULL, 0U,
                                              nonce, firstkey) != -1) {
         printf("crypto_aead_chacha20poly1305_decrypt() worked with an empty "
                "ciphertext\n");
     }
+    if (m2len != 0) {
+        printf("Message length should have been set to zero after a failure\n");
+    }
 
     memcpy(c, m, MLEN);
     crypto_aead_chacha20poly1305_encrypt(c, &found_clen, c, MLEN,
@@ -234,15 +238,12 @@ tv_ietf(void)
         printf("m != m2\n");
     }
     memset(m2, 0, m2len);
-    if (crypto_aead_chacha20poly1305_ietf_decrypt_detached(m2, &m2len, NULL,
+    if (crypto_aead_chacha20poly1305_ietf_decrypt_detached(m2, NULL,
                                                            c, MLEN, mac,
                                                            ad, ADLEN,
                                                            nonce, firstkey) != 0) {
         printf("crypto_aead_chacha20poly1305_ietf_decrypt_detached() failed\n");
     }
-    if (m2len != MLEN) {
-        printf("detached m2len is not properly set\n");
-    }
     if (memcmp(m, m2, MLEN) != 0) {
         printf("detached m != m2\n");
     }
@@ -278,18 +279,25 @@ tv_ietf(void)
     if (memcmp(m, m2, MLEN) != 0) {
         printf("m != m2 (adlen=0)\n");
     }
-
+    m2len = 1;
     if (crypto_aead_chacha20poly1305_ietf_decrypt(
             m2, &m2len, NULL, c, crypto_aead_chacha20poly1305_ietf_ABYTES / 2, NULL,
             0U, nonce, firstkey) != -1) {
         printf("crypto_aead_chacha20poly1305_ietf_decrypt() worked with a short "
                "ciphertext\n");
     }
+    if (m2len != 0) {
+        printf("Message length should have been set to zero after a failure\n");
+    }
+    m2len = 1;
     if (crypto_aead_chacha20poly1305_ietf_decrypt(m2, &m2len, NULL, c, 0U, NULL, 0U,
                                                   nonce, firstkey) != -1) {
         printf("crypto_aead_chacha20poly1305_ietf_decrypt() worked with an empty "
                "ciphertext\n");
     }
+    if (m2len != 0) {
+        printf("Message length should have been set to zero after a failure\n");
+    }
 
     memcpy(c, m, MLEN);
     crypto_aead_chacha20poly1305_ietf_encrypt(c, &found_clen, c, MLEN,