diff --git a/lib/crypto/poly1305.c b/lib/crypto/poly1305.c
index f313ccc4b4dd..25018e3fb487 100644
--- a/lib/crypto/poly1305.c
+++ b/lib/crypto/poly1305.c
@@ -13,6 +13,7 @@
 #include <linux/module.h>
 #include <linux/string.h>
 #include <linux/unaligned.h>
+#include <linux/kmsan.h>
 
 #ifdef CONFIG_CRYPTO_LIB_POLY1305_ARCH
 #include "poly1305.h" /* $(SRCARCH)/poly1305.h */
@@ -31,6 +32,7 @@ void poly1305_init(struct poly1305_desc_ctx *desc,
 	desc->s[3] = get_unaligned_le32(key + 28);
 	desc->buflen = 0;
 	poly1305_block_init(&desc->state, key);
+	kmsan_unpoison_memory(desc, sizeof(struct poly1305_desc_ctx));
 }
 EXPORT_SYMBOL(poly1305_init);