Commit 210d4e9c authored by Kees Cook's avatar Kees Cook Committed by Jakub Kicinski
Browse files

ipv4/igmp: Annotate struct ip_sf_socklist 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 ip_sf_socklist.

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



Cc: Martin KaFai Lau <martin.lau@kernel.org>
Cc: Alexei Starovoitov <ast@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/20230922172858.3822653-2-keescook@chromium.org


Signed-off-by: default avatarJakub Kicinski <kuba@kernel.org>
parent 5b98fd5d

include/linux/igmp.h

+1 −1
Original line number Diff line number Diff line
@@ -39,7 +39,7 @@ struct ip_sf_socklist { 
	unsigned int		sl_max;

	unsigned int		sl_count;

	struct rcu_head		rcu;

	__be32			sl_addr[];

	__be32			sl_addr[] __counted_by(sl_max);

};



#define IP_SFBLOCK	10	/* allocate this many at once */