From ba21d6367cc2cca8f25fff3bc94b1b8df55fc261 Mon Sep 17 00:00:00 2001 From: "Gustavo A. R. Silva" Date: Mon, 9 Oct 2023 15:30:17 -0600 Subject: [PATCH] soc: qcom: apr: Add __counted_by for struct apr_rx_buf 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: Justin Stitt Reviewed-by: Kees Cook Link: https://lore.kernel.org/r/ZSRw6RNi3Crhd32H@work Signed-off-by: Bjorn Andersson --- drivers/soc/qcom/apr.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/drivers/soc/qcom/apr.c b/drivers/soc/qcom/apr.c index 30f81d6d9d9d..1f8b315576a4 100644 --- a/drivers/soc/qcom/apr.c +++ b/drivers/soc/qcom/apr.c @@ -41,7 +41,7 @@ struct packet_router { struct apr_rx_buf { struct list_head node; int len; - uint8_t buf[]; + uint8_t buf[] __counted_by(len); }; /** @@ -171,7 +171,7 @@ static int apr_callback(struct rpmsg_device *rpdev, void *buf, return -EINVAL; } - abuf = kzalloc(sizeof(*abuf) + len, GFP_ATOMIC); + abuf = kzalloc(struct_size(abuf, buf, len), GFP_ATOMIC); if (!abuf) return -ENOMEM; -- 2.25.1