fscrypt: don't load ->i_crypt_info before it's known to be valid

In fscrypt_set_bio_crypt_ctx(), ->i_crypt_info isn't known to be
non-NULL until we check fscrypt_inode_uses_inline_crypto().  So, load
->i_crypt_info after the check rather than before.  This makes no
difference currently, but it prevents people from introducing bugs where
the pointer is dereferenced when it may be NULL.

Suggested-by: Dave Chinner <david@fromorbit.com>
Cc: Satya Tangirala <satyat@google.com>
Link: https://lore.kernel.org/r/20200727174158.121456-1-ebiggers@kernel.org
Signed-off-by: Eric Biggers <ebiggers@google.com>
This commit is contained in:
Eric Biggers 2020-07-27 10:41:58 -07:00
parent 880253eacd
commit 55e32c54bb
1 changed files with 2 additions and 1 deletions

View File

@ -244,11 +244,12 @@ static void fscrypt_generate_dun(const struct fscrypt_info *ci, u64 lblk_num,
void fscrypt_set_bio_crypt_ctx(struct bio *bio, const struct inode *inode,
u64 first_lblk, gfp_t gfp_mask)
{
const struct fscrypt_info *ci = inode->i_crypt_info;
const struct fscrypt_info *ci;
u64 dun[BLK_CRYPTO_DUN_ARRAY_SIZE];
if (!fscrypt_inode_uses_inline_crypto(inode))
return;
ci = inode->i_crypt_info;
fscrypt_generate_dun(ci, first_lblk, dun);
bio_crypt_set_ctx(bio, &ci->ci_enc_key.blk_key->base, dun, gfp_mask);