[PATCH] scsi: qedf: replace memset/memcpy with safer strscpy

[Colin King <colin.king@canonical.com>]

From: Colin Ian King <colin.king@canonical.com>

Currently the qedf_dbg_* family of functions can overrun the end
of the source string if it is less than the destination buffer
length because of the use of a fixed sized memcpy. Replace the
memset/memcpy calls with the safer strscpy as this won't overrun
the end of the source string and it ensures the destination
string is always terminated with NUL.

Addresses-Coverity: ("Out-of-bounds access")
Fixes: 61d8658b4a43 ("scsi: qedf: Add QLogic FastLinQ offload FCoE driver framework.")
Signed-off-by: Colin Ian King <colin.king@canonical.com>
---
 drivers/scsi/qedf/qedf_dbg.c | 12 ++++--------
 1 file changed, 4 insertions(+), 8 deletions(-)

diff --git a/drivers/scsi/qedf/qedf_dbg.c b/drivers/scsi/qedf/qedf_dbg.c
index f2397ee9ba69..b491bebeaca9 100644
--- a/drivers/scsi/qedf/qedf_dbg.c
+++ b/drivers/scsi/qedf/qedf_dbg.c
@@ -17,8 +17,7 @@ qedf_dbg_err(struct qedf_dbg_ctx *qedf, const char *func, u32 line,
 	struct va_format vaf;
 	char nfunc[32];
 
-	memset(nfunc, 0, sizeof(nfunc));
-	memcpy(nfunc, func, sizeof(nfunc) - 1);
+	strscpy(nfunc, func, sizeof(nfunc));
 
 	va_start(va, fmt);
 
@@ -42,8 +41,7 @@ qedf_dbg_warn(struct qedf_dbg_ctx *qedf, const char *func, u32 line,
 	struct va_format vaf;
 	char nfunc[32];
 
-	memset(nfunc, 0, sizeof(nfunc));
-	memcpy(nfunc, func, sizeof(nfunc) - 1);
+	strscpy(nfunc, func, sizeof(nfunc));
 
 	va_start(va, fmt);
 
@@ -71,8 +69,7 @@ qedf_dbg_notice(struct qedf_dbg_ctx *qedf, const char *func, u32 line,
 	struct va_format vaf;
 	char nfunc[32];
 
-	memset(nfunc, 0, sizeof(nfunc));
-	memcpy(nfunc, func, sizeof(nfunc) - 1);
+	strscpy(nfunc, func, sizeof(nfunc));
 
 	va_start(va, fmt);
 
@@ -101,8 +98,7 @@ qedf_dbg_info(struct qedf_dbg_ctx *qedf, const char *func, u32 line,
 	struct va_format vaf;
 	char nfunc[32];
 
-	memset(nfunc, 0, sizeof(nfunc));
-	memcpy(nfunc, func, sizeof(nfunc) - 1);
+	strscpy(nfunc, func, sizeof(nfunc));
 
 	va_start(va, fmt);
 
-- 
2.20.1