Commit ba21d636 authored by Gustavo A. R. Silva's avatar Gustavo A. R. Silva Committed by Bjorn Andersson
Browse files

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: default avatar"Gustavo A. R. Silva" <gustavoars@kernel.org>
Reviewed-by: default avatarJustin Stitt <justinstitt@google.com>
Reviewed-by: default avatarKees Cook <keescook@chromium.org>
Link: https://lore.kernel.org/r/ZSRw6RNi3Crhd32H@work


Signed-off-by: default avatarBjorn Andersson <andersson@kernel.org>
parent f86955f2

drivers/soc/qcom/apr.c

+2 −2
Original line number Diff line number Diff line
@@ -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;