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 ffs_buffer. [1] https://github.com/kees/kernel-tools/blob/trunk/coccinelle/examples/counted_by.cocci Cc: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> Cc: John Keeping <john@xxxxxxxxxxxxx> Cc: Udipto Goswami <quic_ugoswami@xxxxxxxxxxx> Cc: Linyu Yuan <quic_linyyuan@xxxxxxxxxxx> Cc: linux-usb@xxxxxxxxxxxxxxx Signed-off-by: Kees Cook <keescook@xxxxxxxxxxxx> --- drivers/usb/gadget/function/f_fs.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/usb/gadget/function/f_fs.c b/drivers/usb/gadget/function/f_fs.c index 6e9ef35a43a7..af400d083777 100644 --- a/drivers/usb/gadget/function/f_fs.c +++ b/drivers/usb/gadget/function/f_fs.c @@ -202,7 +202,7 @@ struct ffs_epfile { struct ffs_buffer { size_t length; char *data; - char storage[]; + char storage[] __counted_by(length); }; /* ffs_io_data structure ***************************************************/ -- 2.34.1
