Commit aade1533 authored by Kees Cook's avatar Kees Cook
Browse files

afs: Annotate struct afs_permits 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 afs_permits.

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



Cc: David Howells <dhowells@redhat.com>
Cc: Marc Dionne <marc.dionne@auristor.com>
Cc: linux-afs@lists.infradead.org
Reviewed-by: default avatar"Gustavo A. R. Silva" <gustavoars@kernel.org>
Link: https://lore.kernel.org/r/20230915201456.never.529-kees@kernel.org


Signed-off-by: default avatarKees Cook <keescook@chromium.org>
parent 5234193e

fs/afs/internal.h

+1 −1
Original line number Diff line number Diff line
@@ -705,7 +705,7 @@ struct afs_permits { 
	refcount_t		usage;

	unsigned short		nr_permits;	/* Number of records */

	bool			invalidated;	/* Invalidated due to key change */

	struct afs_permit	permits[];	/* List of permits sorted by key pointer */

	struct afs_permit	permits[] __counted_by(nr_permits);	/* List of permits sorted by key pointer */

};



/*