[Buildroot] [2025.02.x, PATCH 1/2] package/iperf3: add patch to fix CVE-2025-54349

[Thomas Perale]

Fixes the following vulnerability:

- CVE-2025-54349

    In iperf before 3.19.1, iperf_auth.c has an off-by-one error and
    resultant heap-based buffer overflow.

For more information, see:
  - https://www.cve.org/CVERecord?id=CVE-2025-54349
  - https://github.com/esnet/iperf/commit/4e5313bab0b9b3fe03513ab54f722c8a3e4b7bdf

Signed-off-by: Thomas Perale <thomas.perale at mind.be>
---
 ...Fix-off-by-one-head-overflow-in-auth.patch | 93 +++++++++++++++++++
 package/iperf3/iperf3.mk                      |  3 +
 2 files changed, 96 insertions(+)
 create mode 100644 package/iperf3/0001-Fix-off-by-one-head-overflow-in-auth.patch

diff --git a/package/iperf3/0001-Fix-off-by-one-head-overflow-in-auth.patch b/package/iperf3/0001-Fix-off-by-one-head-overflow-in-auth.patch
new file mode 100644
index 0000000000..38fe1327ce
--- /dev/null
+++ b/package/iperf3/0001-Fix-off-by-one-head-overflow-in-auth.patch
@@ -0,0 +1,93 @@
+From 4e5313bab0b9b3fe03513ab54f722c8a3e4b7bdf Mon Sep 17 00:00:00 2001
+From: Sarah Larsen <swlarsen at es.net>
+Date: Wed, 25 Jun 2025 15:11:03 +0000
+Subject: [PATCH] Fix off-by-one heap overflow in auth.
+
+Reported by Han Lee (Apple Information Security)
+
+CVE: CVE-2025-54349
+Upstream: https://github.com/esnet/iperf/commit/4e5313bab0b9b3fe03513ab54f722c8a3e4b7bdf
+Signed-off-by: Thomas Perale <thomas.perale at mind.be>
+---
+ src/iperf_auth.c | 18 +++++++++++++-----
+ 1 file changed, 13 insertions(+), 5 deletions(-)
+
+diff --git a/src/iperf_auth.c b/src/iperf_auth.c
+index b9f2bc0f2..632f03d24 100644
+--- a/src/iperf_auth.c
++++ b/src/iperf_auth.c
+@@ -288,6 +288,7 @@ int encrypt_rsa_message(const char *plaintext, EVP_PKEY *public_key, unsigned ch
+ }
+ 
+ int decrypt_rsa_message(const unsigned char *encryptedtext, const int encryptedtext_len, EVP_PKEY *private_key, unsigned char **plaintext, int use_pkcs1_padding) {
++    int ret =0;
+ #if OPENSSL_VERSION_MAJOR >= 3
+     EVP_PKEY_CTX *ctx;
+ #else
+@@ -310,7 +311,8 @@ int decrypt_rsa_message(const unsigned char *encryptedtext, const int encryptedt
+     keysize = RSA_size(rsa);
+ #endif
+     rsa_buffer  = OPENSSL_malloc(keysize * 2);
+-    *plaintext = (unsigned char*)OPENSSL_malloc(keysize);
++    // Note: +1 for NULL
++    *plaintext = (unsigned char*)OPENSSL_malloc(keysize + 1);
+ 
+     BIO *bioBuff   = BIO_new_mem_buf((void*)encryptedtext, encryptedtext_len);
+     rsa_buffer_len = BIO_read(bioBuff, rsa_buffer, keysize * 2);
+@@ -320,13 +322,15 @@ int decrypt_rsa_message(const unsigned char *encryptedtext, const int encryptedt
+         padding = RSA_PKCS1_PADDING;
+     }
+ #if OPENSSL_VERSION_MAJOR >= 3
++
+     plaintext_len = keysize;
+     EVP_PKEY_decrypt_init(ctx);
+-    int ret = EVP_PKEY_CTX_set_rsa_padding(ctx, padding);
++
++    ret = EVP_PKEY_CTX_set_rsa_padding(ctx, padding);
+     if (ret < 0){
+         goto errreturn;
+     }
+-    EVP_PKEY_decrypt(ctx, *plaintext, &plaintext_len, rsa_buffer, rsa_buffer_len);
++    ret = EVP_PKEY_decrypt(ctx, *plaintext, &plaintext_len, rsa_buffer, rsa_buffer_len);
+     EVP_PKEY_CTX_free(ctx);
+ #else
+     plaintext_len = RSA_private_decrypt(rsa_buffer_len, rsa_buffer, *plaintext, rsa, padding);
+@@ -337,7 +341,7 @@ int decrypt_rsa_message(const unsigned char *encryptedtext, const int encryptedt
+     BIO_free(bioBuff);
+ 
+     /* Treat a decryption error as an empty string. */
+-    if (plaintext_len < 0) {
++    if (plaintext_len <= 0) {
+         plaintext_len = 0;
+     }
+ 
+@@ -386,24 +390,28 @@ int decode_auth_setting(int enable_debug, const char *authtoken, EVP_PKEY *priva
+     int plaintext_len;
+     plaintext_len = decrypt_rsa_message(encrypted_b64, encrypted_len_b64, private_key, &plaintext, use_pkcs1_padding);
+     free(encrypted_b64);
+-    if (plaintext_len < 0) {
++    if (plaintext_len <= 0) {
+         return -1;
+     }
++
+     plaintext[plaintext_len] = '\0';
+ 
+     char *s_username, *s_password;
+     s_username = (char *) calloc(plaintext_len, sizeof(char));
+     if (s_username == NULL) {
++        OPENSSL_free(plaintext);
+ 	return -1;
+     }
+     s_password = (char *) calloc(plaintext_len, sizeof(char));
+     if (s_password == NULL) {
++        OPENSSL_free(plaintext);
+ 	free(s_username);
+ 	return -1;
+     }
+ 
+     int rc = sscanf((char *) plaintext, auth_text_format, s_username, s_password, &utc_seconds);
+     if (rc != 3) {
++        OPENSSL_free(plaintext);
+ 	free(s_password);
+ 	free(s_username);
+ 	return -1;
diff --git a/package/iperf3/iperf3.mk b/package/iperf3/iperf3.mk
index 744ee070a4..c5efb1d784 100644
--- a/package/iperf3/iperf3.mk
+++ b/package/iperf3/iperf3.mk
@@ -11,6 +11,9 @@ IPERF3_LICENSE = BSD-3-Clause, BSD-2-Clause, MIT
 IPERF3_LICENSE_FILES = LICENSE
 IPERF3_CPE_ID_VENDOR = es
 
+# 0001-Fix-off-by-one-head-overflow-in-auth.patch
+IPERF3_IGNORE_CVES += CVE-2025-54349
+
 IPERF3_CONF_ENV += CFLAGS="$(TARGET_CFLAGS) -D_GNU_SOURCE"
 
 ifeq ($(BR2_PACKAGE_OPENSSL),y)
-- 
2.50.1