Prepare for the coming implementation by GCC and Clang of the __counted_by attribute. Flexible array members annotated with __counted_by can have their accesses bounds-checked at run-time checking via CONFIG_UBSAN_BOUNDS (for array indexing) and CONFIG_FORTIFY_SOURCE (for strcpy/memcpy-family functions). As found with Coccinelle[1], add __counted_by for struct urb_priv. [1] https://github.com/kees/kernel-tools/blob/trunk/coccinelle/examples/counted_by.cocci Cc: Alan Stern <stern@xxxxxxxxxxxxxxxxxxx> Cc: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> Cc: Mathias Nyman <mathias.nyman@xxxxxxxxx> Cc: linux-usb@xxxxxxxxxxxxxxx Signed-off-by: Kees Cook <keescook@xxxxxxxxxxxx> --- drivers/usb/host/ohci.h | 2 +- drivers/usb/host/xhci.h | 2 +- 2 files changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/usb/host/ohci.h b/drivers/usb/host/ohci.h index aac6285b37f8..1aba22784e05 100644 --- a/drivers/usb/host/ohci.h +++ b/drivers/usb/host/ohci.h @@ -337,7 +337,7 @@ typedef struct urb_priv { u16 length; // # tds in this request u16 td_cnt; // tds already serviced struct list_head pending; - struct td *td[]; // all TDs in this request + struct td *td[] __counted_by(length); // all TDs in this request } urb_priv_t; diff --git a/drivers/usb/host/xhci.h b/drivers/usb/host/xhci.h index 7e282b4522c0..2f21c3a8565c 100644 --- a/drivers/usb/host/xhci.h +++ b/drivers/usb/host/xhci.h @@ -1666,7 +1666,7 @@ struct xhci_scratchpad { struct urb_priv { int num_tds; int num_tds_done; - struct xhci_td td[]; + struct xhci_td td[] __counted_by(num_tds); }; /* -- 2.34.1
