staging/rts5208: Fix read overflow in memcpy

Noticed by FORTIFY_SOURCE, this swaps memcpy() for strncpy() to zero-value
fill the end of the buffer instead of over-reading a string from .rodata.

Signed-off-by: Daniel Micay <danielmicay@gmail.com>
[kees: wrote commit log]
Signed-off-by: Kees Cook <keescook@chromium.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Wayne Porter <wporter82@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/staging/rts5208/rtsx_scsi.c b/drivers/staging/rts5208/rtsx_scsi.c
index a95c5de..36b5a11 100644 (file)
--- a/drivers/staging/rts5208/rtsx_scsi.c
+++ b/drivers/staging/rts5208/rtsx_scsi.c
@@ -536,7 +536,7 @@ static int inquiry(struct scsi_cmnd *srb, struct rtsx_chip *chip)
 
        if (sendbytes > 8) {
                memcpy(buf, inquiry_buf, 8);
-               memcpy(buf + 8, inquiry_string, sendbytes - 8);
+               strncpy(buf + 8, inquiry_string, sendbytes - 8);
                if (pro_formatter_flag) {
                        /* Additional Length */
                        buf[4] = 0x33;