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From:   Jijie Shao <shaojijie@huawei.com>
To:     <yisen.zhuang@huawei.com>, <salil.mehta@huawei.com>,
        <davem@davemloft.net>, <edumazet@google.com>, <kuba@kernel.org>,
        <pabeni@redhat.com>
CC:     <shenjian15@huawei.com>, <wangjie125@huawei.com>,
        <liuyonglong@huawei.com>, <chenhao418@huawei.com>,
        <shaojijie@huawei.com>, <netdev@vger.kernel.org>,
        <linux-kernel@vger.kernel.org>, <stable@vger.kernel.org>
Subject: [PATCH net] net: hns3: fix strscpy causing content truncation issue
Date:   Wed, 9 Aug 2023 10:09:02 +0800
Message-ID: <20230809020902.1941471-1-shaojijie@huawei.com>
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From: Hao Chen <chenhao418@huawei.com>

hns3_dbg_fill_content()/hclge_dbg_fill_content() is aim to integrate some
items to a string for content, and we add '\n' and '\0' in the last
two bytes of content.

strscpy() will add '\0' in the last byte of destination buffer(one of
items), it result in finishing content print ahead of schedule and some
dump content truncation.

One Error log shows as below:
cat mac_list/uc
UC MAC_LIST:

Expected:
UC MAC_LIST:
FUNC_ID  MAC_ADDR            STATE
pf       00:2b:19:05:03:00   ACTIVE

The destination buffer is length-bounded and not required to be
NUL-terminated, so just change strscpy() to memcpy() to fix it.

Fixes: 1cf3d5567f27 ("net: hns3: fix strncpy() not using dest-buf length as length issue")
Signed-off-by: Hao Chen <chenhao418@huawei.com>
Signed-off-by: Jijie Shao <shaojijie@huawei.com>
---
 drivers/net/ethernet/hisilicon/hns3/hns3_debugfs.c         | 4 ++--
 drivers/net/ethernet/hisilicon/hns3/hns3pf/hclge_debugfs.c | 4 ++--
 2 files changed, 4 insertions(+), 4 deletions(-)

diff --git a/drivers/net/ethernet/hisilicon/hns3/hns3_debugfs.c b/drivers/net/ethernet/hisilicon/hns3/hns3_debugfs.c
index 52546f625c8b..f276b5ecb431 100644
--- a/drivers/net/ethernet/hisilicon/hns3/hns3_debugfs.c
+++ b/drivers/net/ethernet/hisilicon/hns3/hns3_debugfs.c
@@ -464,9 +464,9 @@ static void hns3_dbg_fill_content(char *content, u16 len,
 		if (result) {
 			if (item_len < strlen(result[i]))
 				break;
-			strscpy(pos, result[i], strlen(result[i]));
+			memcpy(pos, result[i], strlen(result[i]));
 		} else {
-			strscpy(pos, items[i].name, strlen(items[i].name));
+			memcpy(pos, items[i].name, strlen(items[i].name));
 		}
 		pos += item_len;
 		len -= item_len;
diff --git a/drivers/net/ethernet/hisilicon/hns3/hns3pf/hclge_debugfs.c b/drivers/net/ethernet/hisilicon/hns3/hns3pf/hclge_debugfs.c
index 409db2e70965..0fb2eaee3e8a 100644
--- a/drivers/net/ethernet/hisilicon/hns3/hns3pf/hclge_debugfs.c
+++ b/drivers/net/ethernet/hisilicon/hns3/hns3pf/hclge_debugfs.c
@@ -111,9 +111,9 @@ static void hclge_dbg_fill_content(char *content, u16 len,
 		if (result) {
 			if (item_len < strlen(result[i]))
 				break;
-			strscpy(pos, result[i], strlen(result[i]));
+			memcpy(pos, result[i], strlen(result[i]));
 		} else {
-			strscpy(pos, items[i].name, strlen(items[i].name));
+			memcpy(pos, items[i].name, strlen(items[i].name));
 		}
 		pos += item_len;
 		len -= item_len;
-- 
2.30.0