diff mbox series

[net-next,v3,2/3] net: hns3: fix strncpy() not using dest-buf length as length issue

Message ID 20230621123309.34381-3-lanhao@huawei.com (mailing list archive)
State Accepted
Commit 1cf3d5567f273a8746d1bade00633a93204f80f0
Delegated to: Netdev Maintainers
Headers show
Series net: hns3: There are some cleanup for the HNS3 ethernet driver | expand

Checks

Context Check Description
netdev/series_format success Posting correctly formatted
netdev/tree_selection success Clearly marked for net-next
netdev/fixes_present success Fixes tag not required for -next series
netdev/header_inline success No static functions without inline keyword in header files
netdev/build_32bit success Errors and warnings before: 9 this patch: 8
netdev/cc_maintainers warning 3 maintainers not CCed: guoren@kernel.org huangguangbin2@huawei.com linux-csky@vger.kernel.org
netdev/build_clang success Errors and warnings before: 8 this patch: 8
netdev/verify_signedoff success Signed-off-by tag matches author and committer
netdev/deprecated_api success None detected
netdev/check_selftest success No net selftest shell script
netdev/verify_fixes success No Fixes tag
netdev/build_allmodconfig_warn success Errors and warnings before: 10 this patch: 8
netdev/checkpatch success total: 0 errors, 0 warnings, 0 checks, 83 lines checked
netdev/kdoc success Errors and warnings before: 0 this patch: 0
netdev/source_inline success Was 0 now: 0

Commit Message

Hao Lan June 21, 2023, 12:33 p.m. UTC 
From: Hao Chen <chenhao418@huawei.com>

Now, strncpy() in hns3_dbg_fill_content() use src-length as copy-length,
it may result in dest-buf overflow.

This patch is to fix intel compile warning for csky-linux-gcc (GCC) 12.1.0
compiler.

The warning reports as below:

hclge_debugfs.c:92:25: warning: 'strncpy' specified bound depends on
the length of the source argument [-Wstringop-truncation]

strncpy(pos, items[i].name, strlen(items[i].name));

hclge_debugfs.c:90:25: warning: 'strncpy' output truncated before
terminating nul copying as many bytes from a string as its length
[-Wstringop-truncation]

strncpy(pos, result[i], strlen(result[i]));

strncpy() use src-length as copy-length, it may result in
dest-buf overflow.

So,this patch add some values check to avoid this issue.

Signed-off-by: Hao Chen <chenhao418@huawei.com>
Reported-by: kernel test robot <lkp@intel.com>
Closes: https://lore.kernel.org/lkml/202207170606.7WtHs9yS-lkp@intel.com/T/
Signed-off-by: Hao Lan <lanhao@huawei.com>
---
ChangeLog:
v2-v3:
Use strscpy instead of strncpy
suggested by Paolo Abeni.
v1->v2:
Use strcpy substitutes for memcpy
suggested by Simon Horman.
---
 .../ethernet/hisilicon/hns3/hns3_debugfs.c    | 31 ++++++++++++++-----
 .../hisilicon/hns3/hns3pf/hclge_debugfs.c     | 29 ++++++++++++++---
 2 files changed, 48 insertions(+), 12 deletions(-)
diff mbox series

Patch

diff --git a/drivers/net/ethernet/hisilicon/hns3/hns3_debugfs.c b/drivers/net/ethernet/hisilicon/hns3/hns3_debugfs.c
index d385ffc21876..32bb14303473 100644
--- a/drivers/net/ethernet/hisilicon/hns3/hns3_debugfs.c
+++ b/drivers/net/ethernet/hisilicon/hns3/hns3_debugfs.c
@@ -438,19 +438,36 @@  static void hns3_dbg_fill_content(char *content, u16 len,
 				  const struct hns3_dbg_item *items,
 				  const char **result, u16 size)
 {
+#define HNS3_DBG_LINE_END_LEN	2
 	char *pos = content;
+	u16 item_len;
 	u16 i;
 
+	if (!len) {
+		return;
+	} else if (len <= HNS3_DBG_LINE_END_LEN) {
+		*pos++ = '\0';
+		return;
+	}
+
 	memset(content, ' ', len);
-	for (i = 0; i < size; i++) {
-		if (result)
-			strncpy(pos, result[i], strlen(result[i]));
-		else
-			strncpy(pos, items[i].name, strlen(items[i].name));
+	len -= HNS3_DBG_LINE_END_LEN;
 
-		pos += strlen(items[i].name) + items[i].interval;
+	for (i = 0; i < size; i++) {
+		item_len = strlen(items[i].name) + items[i].interval;
+		if (len < item_len)
+			break;
+
+		if (result) {
+			if (item_len < strlen(result[i]))
+				break;
+			strscpy(pos, result[i], strlen(result[i]));
+		} else {
+			strscpy(pos, items[i].name, strlen(items[i].name));
+		}
+		pos += item_len;
+		len -= item_len;
 	}
-
 	*pos++ = '\n';
 	*pos++ = '\0';
 }
diff --git a/drivers/net/ethernet/hisilicon/hns3/hns3pf/hclge_debugfs.c b/drivers/net/ethernet/hisilicon/hns3/hns3pf/hclge_debugfs.c
index a0b46e7d863e..233c132dc513 100644
--- a/drivers/net/ethernet/hisilicon/hns3/hns3pf/hclge_debugfs.c
+++ b/drivers/net/ethernet/hisilicon/hns3/hns3pf/hclge_debugfs.c
@@ -88,16 +88,35 @@  static void hclge_dbg_fill_content(char *content, u16 len,
 				   const struct hclge_dbg_item *items,
 				   const char **result, u16 size)
 {
+#define HCLGE_DBG_LINE_END_LEN	2
 	char *pos = content;
+	u16 item_len;
 	u16 i;
 
+	if (!len) {
+		return;
+	} else if (len <= HCLGE_DBG_LINE_END_LEN) {
+		*pos++ = '\0';
+		return;
+	}
+
 	memset(content, ' ', len);
+	len -= HCLGE_DBG_LINE_END_LEN;
+
 	for (i = 0; i < size; i++) {
-		if (result)
-			strncpy(pos, result[i], strlen(result[i]));
-		else
-			strncpy(pos, items[i].name, strlen(items[i].name));
-		pos += strlen(items[i].name) + items[i].interval;
+		item_len = strlen(items[i].name) + items[i].interval;
+		if (len < item_len)
+			break;
+
+		if (result) {
+			if (item_len < strlen(result[i]))
+				break;
+			strscpy(pos, result[i], strlen(result[i]));
+		} else {
+			strscpy(pos, items[i].name, strlen(items[i].name));
+		}
+		pos += item_len;
+		len -= item_len;
 	}
 	*pos++ = '\n';
 	*pos++ = '\0';