From: Gustavo A. R. Silva Date: Mon, 15 Jun 2020 22:41:12 +0000 (-0500) Subject: cifs: misc: Use array_size() in if-statement controlling expression X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=bf1028a41eaf0ce39518cbdda34cdb717f16364a;p=linux.git cifs: misc: Use array_size() in if-statement controlling expression Use array_size() instead of the open-coded version in the controlling expression of the if statement. Also, while there, use the preferred form for passing a size of a struct. The alternative form where struct name is spelled out hurts readability and introduces an opportunity for a bug when the pointer variable type is changed but the corresponding sizeof that is passed as argument is not. This issue was found with the help of Coccinelle and, audited and fixed manually. Addresses-KSPP-ID: https://github.com/KSPP/linux/issues/83 Signed-off-by: Gustavo A. R. Silva Signed-off-by: Steve French Reviewed-by: Aurelien Aptel Reviewed-by: Kees Cook Signed-off-by: Steve French --- diff --git a/fs/cifs/misc.c b/fs/cifs/misc.c index 56791a692c8be..e44d049142d04 100644 --- a/fs/cifs/misc.c +++ b/fs/cifs/misc.c @@ -844,28 +844,26 @@ setup_aio_ctx_iter(struct cifs_aio_ctx *ctx, struct iov_iter *iter, int rw) struct bio_vec *bv = NULL; if (iov_iter_is_kvec(iter)) { - memcpy(&ctx->iter, iter, sizeof(struct iov_iter)); + memcpy(&ctx->iter, iter, sizeof(*iter)); ctx->len = count; iov_iter_advance(iter, count); return 0; } - if (max_pages * sizeof(struct bio_vec) <= CIFS_AIO_KMALLOC_LIMIT) - bv = kmalloc_array(max_pages, sizeof(struct bio_vec), - GFP_KERNEL); + if (array_size(max_pages, sizeof(*bv)) <= CIFS_AIO_KMALLOC_LIMIT) + bv = kmalloc_array(max_pages, sizeof(*bv), GFP_KERNEL); if (!bv) { - bv = vmalloc(array_size(max_pages, sizeof(struct bio_vec))); + bv = vmalloc(array_size(max_pages, sizeof(*bv))); if (!bv) return -ENOMEM; } - if (max_pages * sizeof(struct page *) <= CIFS_AIO_KMALLOC_LIMIT) - pages = kmalloc_array(max_pages, sizeof(struct page *), - GFP_KERNEL); + if (array_size(max_pages, sizeof(*pages)) <= CIFS_AIO_KMALLOC_LIMIT) + pages = kmalloc_array(max_pages, sizeof(*pages), GFP_KERNEL); if (!pages) { - pages = vmalloc(array_size(max_pages, sizeof(struct page *))); + pages = vmalloc(array_size(max_pages, sizeof(*pages))); if (!pages) { kvfree(bv); return -ENOMEM;