From 73d649e089de328b5ff66e72a71f353588b24640 Mon Sep 17 00:00:00 2001 From: Mingjie Shen Date: Tue, 5 Mar 2024 18:13:28 -0500 Subject: [PATCH] ssl_mail_client: Fix unbounded write of sprintf() These calls to sprintf may overflow buf because opt.mail_from and opt.mail_to are controlled by users. Fix by replacing sprintf with snprintf. Signed-off-by: Mingjie Shen --- programs/ssl/ssl_mail_client.c | 15 ++++++++------- 1 file changed, 8 insertions(+), 7 deletions(-) diff --git a/programs/ssl/ssl_mail_client.c b/programs/ssl/ssl_mail_client.c index febb881c80..f26a23ba4f 100644 --- a/programs/ssl/ssl_mail_client.c +++ b/programs/ssl/ssl_mail_client.c @@ -727,7 +727,7 @@ usage: mbedtls_printf(" > Write MAIL FROM to server:"); fflush(stdout); - len = sprintf((char *) buf, "MAIL FROM:<%s>\r\n", opt.mail_from); + len = snprintf((char *) buf, sizeof(buf), "MAIL FROM:<%s>\r\n", opt.mail_from); ret = write_ssl_and_get_response(&ssl, buf, len); if (ret < 200 || ret > 299) { mbedtls_printf(" failed\n ! server responded with %d\n\n", ret); @@ -739,7 +739,7 @@ usage: mbedtls_printf(" > Write RCPT TO to server:"); fflush(stdout); - len = sprintf((char *) buf, "RCPT TO:<%s>\r\n", opt.mail_to); + len = snprintf((char *) buf, sizeof(buf), "RCPT TO:<%s>\r\n", opt.mail_to); ret = write_ssl_and_get_response(&ssl, buf, len); if (ret < 200 || ret > 299) { mbedtls_printf(" failed\n ! server responded with %d\n\n", ret); @@ -763,11 +763,12 @@ usage: mbedtls_printf(" > Write content to server:"); fflush(stdout); - len = sprintf((char *) buf, "From: %s\r\nSubject: Mbed TLS Test mail\r\n\r\n" - "This is a simple test mail from the " - "Mbed TLS mail client example.\r\n" - "\r\n" - "Enjoy!", opt.mail_from); + len = snprintf((char *) buf, sizeof(buf), + "From: %s\r\nSubject: Mbed TLS Test mail\r\n\r\n" + "This is a simple test mail from the " + "Mbed TLS mail client example.\r\n" + "\r\n" + "Enjoy!", opt.mail_from); ret = write_ssl_data(&ssl, buf, len); len = sprintf((char *) buf, "\r\n.\r\n");