Hi Herbert,
On 1/18/23 10:54 PM, Herbert Xu wrote:
On Wed, Jan 18, 2023 at 10:19:28PM +0800, Tianjia Zhang wrote:
When the cryption total length is zero, GCM cryption call
skcipher_walk_done() will cause an unexpected crash, so skip calling
this function to avoid possible crash when the GCM cryption length
is equal to zero.
Fixes: ae1b83c7d572 ("crypto: arm64/sm4 - add CE implementation for GCM mode")
Signed-off-by: Tianjia Zhang <tianjia.zhang@xxxxxxxxxxxxxxxxx>
---
arch/arm64/crypto/sm4-ce-gcm-glue.c | 12 +++++++-----
1 file changed, 7 insertions(+), 5 deletions(-)
diff --git a/arch/arm64/crypto/sm4-ce-gcm-glue.c b/arch/arm64/crypto/sm4-ce-gcm-glue.c
index c450a2025ca9..9b63bcf9aa85 100644
--- a/arch/arm64/crypto/sm4-ce-gcm-glue.c
+++ b/arch/arm64/crypto/sm4-ce-gcm-glue.c
@@ -178,11 +178,13 @@ static int gcm_crypt(struct aead_request *req, struct skcipher_walk *walk,
kernel_neon_end();
- err = skcipher_walk_done(walk, tail);
- if (err)
- return err;
- if (walk->nbytes)
- kernel_neon_begin();
+ if (walk->nbytes) {
Please do
if (!walk->nbytes)
break;
Thanks for the suggestion, a new patch has been sent.
As an additional improvement, the tail calculation can be removed
entirely because you already set the chunksize so the walker should
only be feeding you multiples of chunksize except at the end.
Cheers
I printed the walk->nbytes of each iteration of the walker, it is not
always multiples of chunksize except at the end when the algorithm test
manager is turned on.
For example, during a GCM encryption process, I get data like this:
total = 4014, nbytes = 2078, tail = 14
total = 1950, nbytes = 16, tail = 0
total = 1934, nbytes = 311, tail = 7
total = 1630, nbytes = 16, tail = 0
total = 1614, nbytes = 16, tail = 0
total = 1598, nbytes = 1598, tail = 14
Is my understanding wrong?
Best regards,
Tianjia
