Commit 1d495f1c authored by Kees Cook's avatar Kees Cook Committed by Steffen Klassert
Browse files

xfrm: Annotate struct xfrm_sec_ctx with __counted_by 

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).

As found with Coccinelle[1], add __counted_by for struct xfrm_sec_ctx.

Cc: Steffen Klassert <steffen.klassert@secunet.com>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: "David S. Miller" <davem@davemloft.net>
Cc: netdev@vger.kernel.org
Link: https://github.com/kees/kernel-tools/blob/trunk/coccinelle/examples/counted_by.cocci

 [1]
Signed-off-by: default avatarKees Cook <keescook@chromium.org>
Reviewed-by: default avatarGustavo A. R. Silva <gustavoars@kernel.org>
Signed-off-by: default avatarSteffen Klassert <steffen.klassert@secunet.com>
parent 5fa4704d

include/uapi/linux/xfrm.h

+2 −1
Original line number Diff line number Diff line
@@ -4,6 +4,7 @@ 


#include <linux/in6.h>

#include <linux/types.h>

#include <linux/stddef.h>



/* All of the structures in this file may not change size as they are

 * passed into the kernel from userspace via netlink sockets.
@@ -33,7 +34,7 @@ struct xfrm_sec_ctx { 
	__u8	ctx_alg;

	__u16	ctx_len;

	__u32	ctx_sid;

	char	ctx_str[];

	char	ctx_str[] __counted_by(ctx_len);

};



/* Security Context Domains of Interpretation */