Mark read/write registers as non-overlapping for bn_qwmulw_{addqw_,}addw()

This does not cause an issue currently, however if called differently to
their current usage, it can lead to an input being overwritten and
incorrect results being generated.

1 files changed, 3 insertions, 3 deletions

diff --git a/src/lib/libcrypto/bn/arch/aarch64/bn_arch.h b/src/lib/libcrypto/bn/arch/aarch64/bn_arch.h
index 66de3682d4..fe6f8a3aea 100644
--- a/src/lib/libcrypto/bn/arch/aarch64/bn_arch.h
+++ b/src/lib/libcrypto/bn/arch/aarch64/bn_arch.h
@@ -1,4 +1,4 @@
-/*      $OpenBSD: bn_arch.h,v 1.12 2023/06/21 07:56:43 jsing Exp $ */
+/*      $OpenBSD: bn_arch.h,v 1.13 2023/07/24 10:21:29 jsing Exp $ */
 /*
  * Copyright (c) 2023 Joel Sing <jsing@openbsd.org>
  *
@@ -241,7 +241,7 @@ bn_qwmulw_addw(BN_ULONG a3, BN_ULONG a2, BN_ULONG a1, BN_ULONG a0, BN_ULONG b,
             "mul     %[c], %[a3], %[b] \n"
             "adcs   %[r3], %[r3], %[c] \n"
             "adc    %[r4], %[r4], xzr  \n"
-            : [c]"+r"(c), [r4]"=&r"(r4), [r3]"=&r"(r3), [r2]"=&r"(r2),
+            : [c]"+&r"(c), [r4]"=&r"(r4), [r3]"=&r"(r3), [r2]"=&r"(r2),
                 [r1]"=&r"(r1), [r0]"=&r"(r0)
             : [a3]"r"(a3), [a2]"r"(a2), [a1]"r"(a1), [a0]"r"(a0), [b]"r"(b)
             : "cc");
@@ -282,7 +282,7 @@ bn_qwmulw_addqw_addw(BN_ULONG a3, BN_ULONG a2, BN_ULONG a1, BN_ULONG a0,
             "adcs   %[r2], %[r2], %[c2] \n"
             "adcs   %[r3], %[r3], %[c3] \n"
             "adc    %[r4], %[r4], xzr   \n"
-            : [d]"+r"(d), [r4]"=&r"(r4), [r3]"=&r"(r3), [r2]"=&r"(r2),
+            : [d]"+&r"(d), [r4]"=&r"(r4), [r3]"=&r"(r3), [r2]"=&r"(r2),
                 [r1]"=&r"(r1), [r0]"=&r"(r0)
             : [a3]"r"(a3), [a2]"r"(a2), [a1]"r"(a1), [a0]"r"(a0), [b]"r"(b),
                 [c3]"r"(c3), [c2]"r"(c2), [c1]"r"(c1), [c0]"r"(c0)