On Mon, Jul 27, 2020 at 10:41:58AM -0700, Eric Biggers wrote:
> From: Eric Biggers <ebiggers@xxxxxxxxxx>
>
> 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@xxxxxxxxxxxxx>
> Cc: Satya Tangirala <satyat@xxxxxxxxxx>
> Signed-off-by: Eric Biggers <ebiggers@xxxxxxxxxx>
> ---
> fs/crypto/inline_crypt.c | 3 ++-
> 1 file changed, 2 insertions(+), 1 deletion(-)
>
> diff --git a/fs/crypto/inline_crypt.c b/fs/crypto/inline_crypt.c
> index dfb06375099ae..b6b8574caa13c 100644
> --- a/fs/crypto/inline_crypt.c
> +++ b/fs/crypto/inline_crypt.c
> @@ -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);
Applied to fscrypt.git#master for 5.9.
- Eric
