diff --git a/tests/sys/sys/buf_ring_test.c b/tests/sys/sys/buf_ring_test.c
index 5ee1b1cc094b..611fb23788cc 100644
--- a/tests/sys/sys/buf_ring_test.c
+++ b/tests/sys/sys/buf_ring_test.c
@@ -1,126 +1,180 @@
 /*-
  * SPDX-License-Identifier: BSD-2-Clause
  *
  * Copyright (c) 2024 Arm Ltd
  */
 
 #include <sys/types.h>
 
 #include <machine/cpu.h>
 #include <machine/cpufunc.h>
 
 #include <errno.h>
+#include <stdint.h>
 
 #include <atf-c.h>
 
 static void critical_enter(void);
 static void critical_exit(void);
 
 #include <sys/buf_ring.h>
 
 static void
 critical_enter(void)
 {
 }
 
 static void
 critical_exit(void)
 {
 }
 
 static void *
 buf_ring_dequeue_peek(struct buf_ring *br)
 {
 	void *val;
 
 	val = buf_ring_peek(br);
 	if (val != NULL)
 		buf_ring_advance_sc(br);
 	return (val);
 }
 
 static void *
 buf_ring_dequeue_peek_clear_sc(struct buf_ring *br)
 {
 	void *val;
 
 	val = buf_ring_peek_clear_sc(br);
 	if (val != NULL)
 		buf_ring_advance_sc(br);
 	return (val);
 }
 
 #define	MC_SC_TEST(dequeue_func)					\
 ATF_TC_WITHOUT_HEAD(dequeue_func);					\
 ATF_TC_BODY(dequeue_func, tc)						\
 {									\
 	struct buf_ring *br;						\
 									\
 	br = buf_ring_alloc(4);						\
 	ATF_REQUIRE_MSG(br != NULL, "buf_ring_alloc returned NULL");	\
 									\
 	ATF_REQUIRE(dequeue_func(br) == NULL);				\
 	ATF_REQUIRE(buf_ring_count(br) == 0);				\
 	ATF_REQUIRE(!buf_ring_full(br));				\
 	ATF_REQUIRE(buf_ring_empty(br));				\
 									\
 	/* Try filling the buf_ring */					\
 	ATF_REQUIRE(buf_ring_enqueue(br, (void *)1) == 0);		\
 	ATF_REQUIRE(buf_ring_enqueue(br, (void *)2) == 0);		\
 	ATF_REQUIRE(buf_ring_enqueue(br, (void *)3) == 0);		\
 	ATF_REQUIRE(buf_ring_enqueue(br, (void *)4) == ENOBUFS);	\
 									\
 	ATF_REQUIRE(buf_ring_count(br) == 3);				\
 	ATF_REQUIRE(buf_ring_full(br));					\
 	ATF_REQUIRE(!buf_ring_empty(br));				\
 									\
 	/* Partially empty it */					\
 	ATF_REQUIRE(dequeue_func(br) == (void *)1);			\
 	ATF_REQUIRE(dequeue_func(br) == (void *)2);			\
 									\
 	ATF_REQUIRE(buf_ring_count(br) == 1);				\
 	ATF_REQUIRE(!buf_ring_full(br));				\
 	ATF_REQUIRE(!buf_ring_empty(br));				\
 									\
 	/* Add more items */						\
 	ATF_REQUIRE(buf_ring_enqueue(br, (void *)5) == 0);		\
 	ATF_REQUIRE(buf_ring_count(br) == 2);				\
 									\
 	/* Finish emptying it */					\
 	ATF_REQUIRE(dequeue_func(br) == (void *)3);			\
 	ATF_REQUIRE(dequeue_func(br) == (void *)5);			\
 	ATF_REQUIRE(dequeue_func(br) == NULL);				\
 									\
 	ATF_REQUIRE(buf_ring_count(br) == 0);				\
 	ATF_REQUIRE(!buf_ring_full(br));				\
 	ATF_REQUIRE(buf_ring_empty(br));				\
 									\
 	for (uintptr_t i = 0; i < 8; i++) {				\
 		ATF_REQUIRE(buf_ring_enqueue(br, (void *)(i + 100)) == 0);  \
 		ATF_REQUIRE(buf_ring_enqueue(br, (void *)(i + 200)) == 0);  \
 		ATF_REQUIRE(buf_ring_enqueue(br, (void *)(i + 300)) == 0);  \
 		ATF_REQUIRE(buf_ring_count(br) == 3);			\
 		ATF_REQUIRE(dequeue_func(br) == (void *)(i + 100));	\
 		ATF_REQUIRE(dequeue_func(br) == (void *)(i + 200));	\
 		ATF_REQUIRE(dequeue_func(br) == (void *)(i + 300));	\
 									\
 		ATF_REQUIRE(!buf_ring_full(br));			\
 		ATF_REQUIRE(buf_ring_empty(br));			\
 	}								\
 									\
 	buf_ring_free(br);						\
 }
 
 MC_SC_TEST(buf_ring_dequeue_sc)
 MC_SC_TEST(buf_ring_dequeue_mc)
 MC_SC_TEST(buf_ring_dequeue_peek)
 MC_SC_TEST(buf_ring_dequeue_peek_clear_sc)
 
+ATF_TC_WITHOUT_HEAD(overflow);
+ATF_TC_BODY(overflow, tc)
+{
+	struct buf_ring *br;
+
+	br = buf_ring_alloc(4);
+	ATF_REQUIRE_MSG(br != NULL, "buf_ring_alloc returned NULL");
+
+	br->br_prod_head = br->br_cons_head = br->br_prod_tail =
+	    br->br_cons_tail = UINT32_MAX - 1;
+	ATF_REQUIRE(buf_ring_count(br) == 0);
+	ATF_REQUIRE(!buf_ring_full(br));
+	ATF_REQUIRE(buf_ring_empty(br));
+
+	ATF_REQUIRE(buf_ring_enqueue(br, (void *)1) == 0);
+	ATF_REQUIRE(buf_ring_count(br) == 1);
+	ATF_REQUIRE(!buf_ring_full(br));
+	ATF_REQUIRE(!buf_ring_empty(br));
+
+	ATF_REQUIRE(buf_ring_enqueue(br, (void *)2) == 0);
+	ATF_REQUIRE(buf_ring_count(br) == 2);
+	ATF_REQUIRE(!buf_ring_full(br));
+	ATF_REQUIRE(!buf_ring_empty(br));
+
+	ATF_REQUIRE(buf_ring_enqueue(br, (void *)3) == 0);
+	ATF_REQUIRE(buf_ring_count(br) == 3);
+	ATF_REQUIRE(buf_ring_full(br));
+	ATF_REQUIRE(!buf_ring_empty(br));
+
+	ATF_REQUIRE(br->br_prod_head == 1);
+	ATF_REQUIRE(br->br_prod_tail == 1);
+	ATF_REQUIRE(br->br_cons_head == UINT32_MAX - 1);
+	ATF_REQUIRE(br->br_cons_tail == UINT32_MAX - 1);
+
+	ATF_REQUIRE(buf_ring_dequeue_sc(br) == (void *)1);
+	ATF_REQUIRE(buf_ring_count(br) == 2);
+	ATF_REQUIRE(!buf_ring_full(br));
+	ATF_REQUIRE(!buf_ring_empty(br));
+
+	ATF_REQUIRE(buf_ring_dequeue_sc(br) == (void *)2);
+	ATF_REQUIRE(buf_ring_count(br) == 1);
+	ATF_REQUIRE(!buf_ring_full(br));
+	ATF_REQUIRE(!buf_ring_empty(br));
+
+	ATF_REQUIRE(buf_ring_dequeue_sc(br) == (void *)3);
+	ATF_REQUIRE(buf_ring_count(br) == 0);
+	ATF_REQUIRE(!buf_ring_full(br));
+	ATF_REQUIRE(buf_ring_empty(br));
+
+	buf_ring_free(br);
+}
+
 ATF_TP_ADD_TCS(tp)
 {
 	ATF_TP_ADD_TC(tp, buf_ring_dequeue_sc);
 	ATF_TP_ADD_TC(tp, buf_ring_dequeue_mc);
 	ATF_TP_ADD_TC(tp, buf_ring_dequeue_peek);
 	ATF_TP_ADD_TC(tp, buf_ring_dequeue_peek_clear_sc);
+	ATF_TP_ADD_TC(tp, overflow);
 	return (atf_no_error());
 }