linux-kernel - [PATCH v3 02/14] lib/mpi: mpi_write_sgl(): fix style issue with lzero decrement

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Message-Id: <1458648768-1469-3-git-send-email-nicstange@gmail.com>
Date:	Tue, 22 Mar 2016 13:12:36 +0100
From:	Nicolai Stange <nicstange@...il.com>
To:	Herbert Xu <herbert@...dor.apana.org.au>,
	"David S. Miller" <davem@...emloft.net>
Cc:	Tadeusz Struk <tadeusz.struk@...el.com>,
	Michal Marek <mmarek@...e.com>,
	Andrzej Zaborowski <andrew.zaborowski@...el.com>,
	Stephan Mueller <smueller@...onox.de>,
	Arnd Bergmann <arnd@...db.de>, linux-crypto@...r.kernel.org,
	linux-kernel@...r.kernel.org, Nicolai Stange <nicstange@...il.com>
Subject: [PATCH v3 02/14] lib/mpi: mpi_write_sgl(): fix style issue with lzero decrement

Within the copying loop in mpi_write_sgl(), we have

  if (lzeros > 0) {
    ...
    lzeros -= sizeof(alimb);
  }

However, at this point, lzeros < sizeof(alimb) holds. Make this fact
explicit by rewriting the above to

  if (lzeros) {
    ...
    lzeros = 0;
  }

Signed-off-by: Nicolai Stange <nicstange@...il.com>
---
 lib/mpi/mpicoder.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/lib/mpi/mpicoder.c b/lib/mpi/mpicoder.c
index 6bb52be..d8b372b 100644
--- a/lib/mpi/mpicoder.c
+++ b/lib/mpi/mpicoder.c
@@ -402,14 +402,14 @@ int mpi_write_to_sgl(MPI a, struct scatterlist *sgl, unsigned *nbytes,
 #else
 #error please implement for this limb size.
 #endif
-		if (lzeros > 0) {
+		if (lzeros) {
 			mpi_limb_t *limb1 = (void *)p - sizeof(alimb);
 			mpi_limb_t *limb2 = (void *)p - sizeof(alimb)
 				+ lzeros;
 			*limb1 = *limb2;
 			p -= lzeros;
 			y = lzeros;
-			lzeros -= sizeof(alimb);
+			lzeros = 0;
 		}
 
 		p = p - (sizeof(alimb) - y);
-- 
2.7.4