Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67;
From:   Greg Kroah-Hartman <gregkh@linuxfoundation.org>
To:     linux-kernel@vger.kernel.org
Cc:     Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        stable@vger.kernel.org, Dan Carpenter <dan.carpenter@oracle.com>,
        Geoff Levand <geoff@infradead.org>,
        Michael Ellerman <mpe@ellerman.id.au>,
        Sasha Levin <sashal@kernel.org>
Subject: [PATCH 4.19 031/306] powerpc: Fix signedness bug in update_flash_db()
Date:   Wed, 27 Nov 2019 21:28:01 +0100
Message-Id: <20191127203117.022103888@linuxfoundation.org>
In-Reply-To: <20191127203114.766709977@linuxfoundation.org>
References: <20191127203114.766709977@linuxfoundation.org>
User-Agent: quilt/0.66
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit
Sender: linux-kernel-owner@vger.kernel.org
Precedence: bulk

From: Dan Carpenter <dan.carpenter@oracle.com>

[ Upstream commit 014704e6f54189a203cc14c7c0bb411b940241bc ]

The "count < sizeof(struct os_area_db)" comparison is type promoted to
size_t so negative values of "count" are treated as very high values
and we accidentally return success instead of a negative error code.

This doesn't really change runtime much but it fixes a static checker
warning.

Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Acked-by: Geoff Levand <geoff@infradead.org>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
 arch/powerpc/platforms/ps3/os-area.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/arch/powerpc/platforms/ps3/os-area.c b/arch/powerpc/platforms/ps3/os-area.c
index cdbfc5cfd6f38..f5387ad822798 100644
--- a/arch/powerpc/platforms/ps3/os-area.c
+++ b/arch/powerpc/platforms/ps3/os-area.c
@@ -664,7 +664,7 @@ static int update_flash_db(void)
 	db_set_64(db, &os_area_db_id_rtc_diff, saved_params.rtc_diff);
 
 	count = os_area_flash_write(db, sizeof(struct os_area_db), pos);
-	if (count < sizeof(struct os_area_db)) {
+	if (count < 0 || count < sizeof(struct os_area_db)) {
 		pr_debug("%s: os_area_flash_write failed %zd\n", __func__,
 			 count);
 		error = count < 0 ? count : -EIO;
-- 
2.20.1