> Calling crypto_free_shash(NULL) is actually fine. Really? > It doesn't dereference the parameter, it just does pointer math on it in > crypto_shash_tfm() and returns if it's NULL in crypto_destroy_tfm(). Can a passed null pointer really work in this function? https://elixir.bootlin.com/linux/v4.16-rc2/source/include/crypto/hash.h#L684 https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/tree/include/crypto/hash.h?id=0f9da844d87796ac31b04e81ee95e155e9043132#n751 static inline struct crypto_tfm *crypto_shash_tfm(struct crypto_shash *tfm) { return &tfm->base; } Regards, Markus
