From: Gustavo A. R. Silva Date: Mon, 9 Oct 2023 19:41:18 +0000 (-0600) Subject: wifi: hostap: Add __counted_by for struct prism2_download_data and use struct_size() X-Git-Tag: v6.7-rc1~160^2~112^2~20 X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=5cf47dc14158f979ee9485fc15e004c0d6952ea7;p=thirdparty%2Fkernel%2Flinux.git wifi: hostap: Add __counted_by for struct prism2_download_data and use struct_size() 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 via CONFIG_UBSAN_BOUNDS (for array indexing) and CONFIG_FORTIFY_SOURCE (for strcpy/memcpy-family functions). While there, use struct_size() helper, instead of the open-coded version, to calculate the size for the allocation of the whole flexible structure, including of course, the flexible-array member. This code was found with the help of Coccinelle, and audited and fixed manually. Signed-off-by: Gustavo A. R. Silva Reviewed-by: Kees Cook Signed-off-by: Kalle Valo Link: https://lore.kernel.org/r/ZSRXXvWMMkm7qqRW@work --- diff --git a/drivers/net/wireless/intersil/hostap/hostap_download.c b/drivers/net/wireless/intersil/hostap/hostap_download.c index 3672291ced5c8..5e5bada28b5b9 100644 --- a/drivers/net/wireless/intersil/hostap/hostap_download.c +++ b/drivers/net/wireless/intersil/hostap/hostap_download.c @@ -732,8 +732,7 @@ static int prism2_download(local_info_t *local, goto out; } - dl = kzalloc(sizeof(*dl) + param->num_areas * - sizeof(struct prism2_download_data_area), GFP_KERNEL); + dl = kzalloc(struct_size(dl, data, param->num_areas), GFP_KERNEL); if (dl == NULL) { ret = -ENOMEM; goto out; diff --git a/drivers/net/wireless/intersil/hostap/hostap_wlan.h b/drivers/net/wireless/intersil/hostap/hostap_wlan.h index c25cd21d18bd9..f71c0545c0be6 100644 --- a/drivers/net/wireless/intersil/hostap/hostap_wlan.h +++ b/drivers/net/wireless/intersil/hostap/hostap_wlan.h @@ -617,7 +617,7 @@ struct prism2_download_data { u32 addr; /* wlan card address */ u32 len; u8 *data; /* allocated data */ - } data[]; + } data[] __counted_by(num_areas); };