staging: dgnc: fix potential format string flaw

Make sure that format strings cannot leak into printk() calls from the
msgbuf string.

Signed-off-by: Kees Cook <keescook@chromium.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/drivers/staging/dgnc/dgnc_driver.c b/drivers/staging/dgnc/dgnc_driver.c
index f8c1e22..71d2b83 100644 (file)
--- a/drivers/staging/dgnc/dgnc_driver.c
+++ b/drivers/staging/dgnc/dgnc_driver.c
@@ -454,7 +454,7 @@ static void dgnc_cleanup_board(struct board_t *brd)
 
                DGNC_LOCK(dgnc_global_lock, flags);
                brd->msgbuf = NULL;
-               printk(brd->msgbuf_head);
+               printk("%s", brd->msgbuf_head);
                kfree(brd->msgbuf_head);
                brd->msgbuf_head = NULL;
                DGNC_UNLOCK(dgnc_global_lock, flags);
@@ -710,7 +710,7 @@ static int dgnc_found_board(struct pci_dev *pdev, int id)
        DPR_INIT(("dgnc_scan(%d) - printing out the msgbuf\n", i));
        DGNC_LOCK(dgnc_global_lock, flags);
        brd->msgbuf = NULL;
-       printk(brd->msgbuf_head);
+       printk("%s", brd->msgbuf_head);
        kfree(brd->msgbuf_head);
        brd->msgbuf_head = NULL;
        DGNC_UNLOCK(dgnc_global_lock, flags);