[PATCH v6 26/39] s390/cpacf: Unpoison the results of cpacf_trng()

Ilya Leoshkevich
2024-06-21T00:27:14Z

Prevent KMSAN from complaining about buffers filled by cpacf_trng()
being uninitialized.

Tested-by: Alexander Gordeev <agordeev@linux.ibm.com>
Reviewed-by: Alexander Potapenko <glider@google.com>
Acked-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Ilya Leoshkevich <iii@linux.ibm.com>
---
arch/s390/include/asm/cpacf.h | 3 +++
1 file changed, 3 insertions(+)

diff --git a/arch/s390/include/asm/cpacf.h b/arch/s390/include/asm/cpacf.h
index c786538e397c..dae8843b164f 100644
--- a/arch/s390/include/asm/cpacf.h
+++ b/arch/s390/include/asm/cpacf.h
@@ -12,6 +12,7 @@
#define _ASM_S390_CPACF_H

#include <asm/facility.h>
+#include <linux/kmsan-checks.h>

/*
* Instruction opcodes for the CPACF instructions
@@ -542,6 +543,8 @@ static inline void cpacf_trng(u8 *ucbuf, unsigned long ucbuf_len,
: [ucbuf] "+&d" (u.pair), [cbuf] "+&d" (c.pair)
: [fc] "K" (CPACF_PRNO_TRNG), [opc] "i" (CPACF_PRNO)
: "cc", "memory", "0");
+ kmsan_unpoison_memory(ucbuf, ucbuf_len);
+ kmsan_unpoison_memory(cbuf, cbuf_len);
}

/**
--
2.45.1