scsi: mptfusion: Avoid possible run-time warning with long manufacturer strings

The prior strscpy() replacement of strncpy() here expected the
manufacture_reply strings to be NUL-terminated, but it is possible
they are not, as the code pattern here shows, e.g., edev->vendor_id
being exactly 1 character larger than manufacture_reply->vendor_id,
and the replaced strncpy() was copying only up to the size of the
source character array. Replace this with memtostr(), which is the
unambiguous way to convert a maybe not-NUL-terminated character array
into a NUL-terminated string.

Reported-by: Charles Bertsch <cbertsch@cox.net>
Closes: https://lore.kernel.org/all/5445ba0f-3e27-4d43-a9ba-0cc22ada2fce@cox.net/
Fixes: 45e833f0e5bb ("scsi: message: fusion: Replace deprecated strncpy() with strscpy()")
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Link: https://lore.kernel.org/r/20240410023155.2100422-2-keescook@chromium.org
Signed-off-by: Kees Cook <keescook@chromium.org>

diff --git a/drivers/message/fusion/mptsas.c b/drivers/message/fusion/mptsas.c
index 300f8e955a5319f92361a607a754e36be1a669d8..0f80c840afc3a26e52a0f0c33f1fa676a20b604a 100644 (file)
--- a/drivers/message/fusion/mptsas.c
+++ b/drivers/message/fusion/mptsas.c
@@ -2964,17 +2964,13 @@ mptsas_exp_repmanufacture_info(MPT_ADAPTER *ioc,
                        goto out_free;
 
                manufacture_reply = data_out + sizeof(struct rep_manu_request);
-               strscpy(edev->vendor_id, manufacture_reply->vendor_id,
-                       sizeof(edev->vendor_id));
-               strscpy(edev->product_id, manufacture_reply->product_id,
-                       sizeof(edev->product_id));
-               strscpy(edev->product_rev, manufacture_reply->product_rev,
-                       sizeof(edev->product_rev));
+               memtostr(edev->vendor_id, manufacture_reply->vendor_id);
+               memtostr(edev->product_id, manufacture_reply->product_id);
+               memtostr(edev->product_rev, manufacture_reply->product_rev);
                edev->level = manufacture_reply->sas_format;
                if (manufacture_reply->sas_format) {
-                       strscpy(edev->component_vendor_id,
-                               manufacture_reply->component_vendor_id,
-                               sizeof(edev->component_vendor_id));
+                       memtostr(edev->component_vendor_id,
+                                manufacture_reply->component_vendor_id);
                        tmp = (u8 *)&manufacture_reply->component_id;
                        edev->component_id = tmp[0] << 8 | tmp[1];
                        edev->component_revision_id =