From 2eb27c11937ee9984c04b75d213a737291c5f58c Mon Sep 17 00:00:00 2001 From: Eric Biggers Date: Thu, 9 Jul 2020 23:20:39 -0700 Subject: crypto: algapi - add NEED_FALLBACK to INHERITED_FLAGS CRYPTO_ALG_NEED_FALLBACK is handled inconsistently. When it's requested to be clear, some templates propagate that request to child algorithms, while others don't. It's apparently desired for NEED_FALLBACK to be propagated, to avoid deadlocks where a module tries to load itself while it's being initialized, and to avoid unnecessarily complex fallback chains where we have e.g. cbc-aes-$driver falling back to cbc(aes-$driver) where aes-$driver itself falls back to aes-generic, instead of cbc-aes-$driver simply falling back to cbc(aes-generic). There have been a number of fixes to this effect: commit 89027579bc6c ("crypto: xts - Propagate NEED_FALLBACK bit") commit d2c2a85cfe82 ("crypto: ctr - Propagate NEED_FALLBACK bit") commit e6c2e65c70a6 ("crypto: cbc - Propagate NEED_FALLBACK bit") But it seems that other templates can have the same problems too. To avoid this whack-a-mole, just add NEED_FALLBACK to INHERITED_FLAGS so that it's always inherited. Signed-off-by: Eric Biggers Signed-off-by: Herbert Xu --- include/linux/crypto.h | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'include/linux/crypto.h') diff --git a/include/linux/crypto.h b/include/linux/crypto.h index 7cd2d00f0a05..f73f0b51e1cd 100644 --- a/include/linux/crypto.h +++ b/include/linux/crypto.h @@ -60,8 +60,8 @@ #define CRYPTO_ALG_ASYNC 0x00000080 /* - * Set this bit if and only if the algorithm requires another algorithm of - * the same type to handle corner cases. + * Set if the algorithm (or an algorithm which it uses) requires another + * algorithm of the same type to handle corner cases. */ #define CRYPTO_ALG_NEED_FALLBACK 0x00000100 -- cgit v1.2.3-59-g8ed1b