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 sidtab_str_cache. [1] https://github.com/kees/kernel-tools/blob/trunk/coccinelle/examples/counted_by.cocci Cc: Paul Moore <paul@xxxxxxxxxxxxxx> Cc: Stephen Smalley <stephen.smalley.work@xxxxxxxxx> Cc: Eric Paris <eparis@xxxxxxxxxxxxxx> Cc: Ondrej Mosnacek <omosnace@xxxxxxxxxx> Cc: selinux@xxxxxxxxxxxxxxx Signed-off-by: Kees Cook <keescook@xxxxxxxxxxxx> --- security/selinux/ss/sidtab.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/security/selinux/ss/sidtab.c b/security/selinux/ss/sidtab.c index d8ead463b8df..732fd8e22a12 100644 --- a/security/selinux/ss/sidtab.c +++ b/security/selinux/ss/sidtab.c @@ -25,7 +25,7 @@ struct sidtab_str_cache { struct list_head lru_member; struct sidtab_entry *parent; u32 len; - char str[]; + char str[] __counted_by(len); }; #define index_to_sid(index) ((index) + SECINITSID_NUM + 1) -- 2.34.1
