On Fri, Jan 11, 2019 at 12:29:28AM +0200, Aaro Koskinen wrote: > Hi, > > On Fri, Jan 04, 2019 at 05:28:02PM +0000, David Howells wrote: > > Eric Biggers <ebiggers@xxxxxxxxxx> wrote: > > > Hi Aaro, thanks for the bug report! I think you're on the right track; it makes > > > much more sense to have the keyrings subsystem store the payload with better > > > alignment, than to work around the 2-byte alignment in fscrypt. > > > > > > But how about '__aligned(__alignof__(u64))' instead? 4 bytes may not be enough. > > > > > > David, what do you think? > > > > Does that even work? > > That should work. > > > Might be better to just insert 6 bytes of padding with a comment, but yes I > > agree that it's probably better to align it to at least machine word size. > > Padding is fragile, e.g. if struct rcu_head changes. Using __aligned should > make it always right automatically. > > A. I agree that __aligned is better. It should work; see 'struct crypto_tfm' in include/linux/crypto.h for another example of a struct that uses __aligned on a flexible array at the end. Aaro, can you send a formal patch? If you don't I'll do so, but I figure I'll ask first. Thanks, - Eric
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