Commit 5b98fd5d authored by Kees Cook's avatar Kees Cook Committed by Jakub Kicinski
Browse files

ipv4: Annotate struct fib_info 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 checking 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 fib_info.

[1] https://github.com/kees/kernel-tools/blob/trunk/coccinelle/examples/counted_by.cocci



Cc: David Ahern <dsahern@kernel.org>
Signed-off-by: default avatarKees Cook <keescook@chromium.org>
Reviewed-by: default avatarGustavo A. R. Silva <gustavoars@kernel.org>
Link: https://lore.kernel.org/r/20230922172858.3822653-1-keescook@chromium.org


Signed-off-by: default avatarJakub Kicinski <kuba@kernel.org>
parent 436e5f75

include/net/ip_fib.h

+1 −1
Original line number Diff line number Diff line
@@ -156,7 +156,7 @@ struct fib_info { 
	bool			nh_updated;

	struct nexthop		*nh;

	struct rcu_head		rcu;

	struct fib_nh		fib_nh[];

	struct fib_nh		fib_nh[] __counted_by(fib_nhs);

};