scsi: target: Replace strncpy() with strscpy() in VPD dump functions

Replace the deprecated[1] strncpy() with strscpy() in
transport_dump_vpd_proto_id(), transport_dump_vpd_assoc(),
transport_dump_vpd_ident_type(), and transport_dump_vpd_ident().

All four functions follow the same pattern: a local
buf[VPD_TMP_BUF_SIZE] (254 bytes) is zeroed with memset(), populated
via sprintf()/snprintf() (always NUL-terminated), then conditionally
copied to p_buf with strncpy(). The p_buf destination is used as a
C string by all callers in target_core_configfs.c: strlen(buf) and
sprintf(page+len, "%s", buf) to build sysfs output.

NUL-padding is not required: callers in target_core_configfs.c
pre-zero p_buf with memset() or initializer before calling these
functions, and consume p_buf only as a NUL-terminated C string via
strlen() and "%s", never exposing trailing bytes.

No behavioral change: the source buf is always NUL-terminated and
shorter than VPD_TMP_BUF_SIZE, so strscpy() produces identical output.

Link: https://github.com/KSPP/linux/issues/90
Signed-off-by: Kees Cook <kees@kernel.org>
Reviewed-by: Kees Cook <keescook@chromium.org>
Link: https://patch.msgid.link/20260323171311.work.101-kees@kernel.org
Signed-off-by: Martin K. Petersen <martin.petersen@oracle.com>

diff --git a/drivers/target/target_core_transport.c b/drivers/target/target_core_transport.c
index 4e8d779dda5e259a1854d66e16828ac6e2c07bb4..fad03a15c969e6d74ad628ae5f10b7f52017fc39 100644 (file)
--- a/drivers/target/target_core_transport.c
+++ b/drivers/target/target_core_transport.c
@@ -1150,7 +1150,7 @@ void transport_dump_vpd_proto_id(
        }
 
        if (p_buf)
-               strncpy(p_buf, buf, p_buf_len);
+               strscpy(p_buf, buf, p_buf_len);
        else
                pr_debug("%s", buf);
 }
@@ -1200,7 +1200,7 @@ int transport_dump_vpd_assoc(
        }
 
        if (p_buf)
-               strncpy(p_buf, buf, p_buf_len);
+               strscpy(p_buf, buf, p_buf_len);
        else
                pr_debug("%s", buf);
 
@@ -1260,7 +1260,7 @@ int transport_dump_vpd_ident_type(
        if (p_buf) {
                if (p_buf_len < strlen(buf)+1)
                        return -EINVAL;
-               strncpy(p_buf, buf, p_buf_len);
+               strscpy(p_buf, buf, p_buf_len);
        } else {
                pr_debug("%s", buf);
        }
@@ -1314,7 +1314,7 @@ int transport_dump_vpd_ident(
        }
 
        if (p_buf)
-               strncpy(p_buf, buf, p_buf_len);
+               strscpy(p_buf, buf, p_buf_len);
        else
                pr_debug("%s", buf);