2022-08-16 09:39:42

by Lei He

[permalink] [raw]
Subject: [PATCH] crypto-virtio: fix memory-leak

From: lei he <[email protected]>

Fix memory-leak for virtio-crypto akcipher request, this problem is
introduced by 59ca6c93387d3(virtio-crypto: implement RSA algorithm).
The leak can be reproduced and tested with the following script
inside virtual machine:

#!/bin/bash

LOOP_TIMES=10000

# required module: pkcs8_key_parser, virtio_crypto
modprobe pkcs8_key_parser # if CONFIG_PKCS8_PRIVATE_KEY_PARSER=m
modprobe virtio_crypto # if CONFIG_CRYPTO_DEV_VIRTIO=m
rm -rf /tmp/data
dd if=/dev/random of=/tmp/data count=1 bs=230

# generate private key and self-signed cert
openssl req -nodes -x509 -newkey rsa:2048 -keyout key.pem \
-outform der -out cert.der \
-subj "/C=CN/ST=GD/L=SZ/O=vihoo/OU=dev/CN=always.com/[email protected]"
# convert private key from pem to der
openssl pkcs8 -in key.pem -topk8 -nocrypt -outform DER -out key.der

# add key
PRIV_KEY_ID=`cat key.der | keyctl padd asymmetric test_priv_key @s`
echo "priv key id = "$PRIV_KEY_ID
PUB_KEY_ID=`cat cert.der | keyctl padd asymmetric test_pub_key @s`
echo "pub key id = "$PUB_KEY_ID

# query key
keyctl pkey_query $PRIV_KEY_ID 0
keyctl pkey_query $PUB_KEY_ID 0

# here we only run pkey_encrypt becasuse it is the fastest interface
function bench_pub() {
keyctl pkey_encrypt $PUB_KEY_ID 0 /tmp/data enc=pkcs1 >/tmp/enc.pub
}

# do bench_pub in loop to obtain the memory leak
for (( i = 0; i < ${LOOP_TIMES}; ++i )); do
bench_pub
done

Signed-off-by: lei he <[email protected]>

# Please enter the commit message for your changes. Lines starting
# with '#' will be kept; you may remove them yourself if you want to.
# An empty message aborts the commit.
#
# Date: Tue Aug 16 11:53:30 2022 +0800
#
# On branch master
# Your branch is ahead of 'origin/master' by 1 commit.
# (use "git push" to publish your local commits)
#
# Changes to be committed:
# modified: drivers/crypto/virtio/virtio_crypto_akcipher_algs.c
#
# Untracked files:
# cert.der
# key.der
# key.pem
#

# Please enter the commit message for your changes. Lines starting
# with '#' will be kept; you may remove them yourself if you want to.
# An empty message aborts the commit.
#
# Date: Tue Aug 16 11:53:30 2022 +0800
#
# On branch master
# Your branch is ahead of 'origin/master' by 1 commit.
# (use "git push" to publish your local commits)
#
# Changes to be committed:
# modified: drivers/crypto/virtio/virtio_crypto_akcipher_algs.c
#
# Untracked files:
# cert.der
# key.der
# key.pem
#

# Please enter the commit message for your changes. Lines starting
# with '#' will be kept; you may remove them yourself if you want to.
# An empty message aborts the commit.
#
# Date: Tue Aug 16 11:53:30 2022 +0800
#
# On branch master
# Your branch is ahead of 'origin/master' by 1 commit.
# (use "git push" to publish your local commits)
#
# Changes to be committed:
# modified: drivers/crypto/virtio/virtio_crypto_akcipher_algs.c
#
# Untracked files:
# cert.der
# key.der
# key.pem
#
---
drivers/crypto/virtio/virtio_crypto_akcipher_algs.c | 4 ++++
1 file changed, 4 insertions(+)

diff --git a/drivers/crypto/virtio/virtio_crypto_akcipher_algs.c b/drivers/crypto/virtio/virtio_crypto_akcipher_algs.c
index 2a60d0525cde..168195672e2e 100644
--- a/drivers/crypto/virtio/virtio_crypto_akcipher_algs.c
+++ b/drivers/crypto/virtio/virtio_crypto_akcipher_algs.c
@@ -56,6 +56,10 @@ static void virtio_crypto_akcipher_finalize_req(
struct virtio_crypto_akcipher_request *vc_akcipher_req,
struct akcipher_request *req, int err)
{
+ kfree(vc_akcipher_req->src_buf);
+ kfree(vc_akcipher_req->dst_buf);
+ vc_akcipher_req->src_buf = NULL;
+ vc_akcipher_req->dst_buf = NULL;
virtcrypto_clear_request(&vc_akcipher_req->base);

crypto_finalize_akcipher_request(vc_akcipher_req->base.dataq->engine, req, err);
--
2.20.1


2022-08-16 10:30:42

by Gonglei (Arei)

[permalink] [raw]
Subject: RE: [PATCH] crypto-virtio: fix memory-leak



> -----Original Message-----
> From: Michael S. Tsirkin [mailto:[email protected]]
> Sent: Tuesday, August 16, 2022 4:43 PM
> To: Lei He <[email protected]>
> Cc: Gonglei (Arei) <[email protected]>;
> [email protected]; [email protected];
> [email protected]; [email protected];
> [email protected]
> Subject: Re: [PATCH] crypto-virtio: fix memory-leak
>

Pls 's/crypto-virtio/virtio-crypto' in order to keep consistency.

Reviewed-by: Gonglei <[email protected]>

Regards,
-Gonglei

> On Tue, Aug 16, 2022 at 03:59:16PM +0800, Lei He wrote:
> > From: lei he <[email protected]>
> >
> > Fix memory-leak for virtio-crypto akcipher request, this problem is
> > introduced by 59ca6c93387d3(virtio-crypto: implement RSA algorithm).
> > The leak can be reproduced and tested with the following script inside
> > virtual machine:
> >
> > #!/bin/bash
> >
> > LOOP_TIMES=10000
> >
> > # required module: pkcs8_key_parser, virtio_crypto modprobe
> > pkcs8_key_parser # if CONFIG_PKCS8_PRIVATE_KEY_PARSER=m modprobe
> > virtio_crypto # if CONFIG_CRYPTO_DEV_VIRTIO=m rm -rf /tmp/data dd
> > if=/dev/random of=/tmp/data count=1 bs=230
> >
> > # generate private key and self-signed cert openssl req -nodes -x509
> > -newkey rsa:2048 -keyout key.pem \
> > -outform der -out cert.der \
> > -subj
> "/C=CN/ST=GD/L=SZ/O=vihoo/OU=dev/CN=always.com/emailAddress=yy@
> always.com"
> > # convert private key from pem to der
> > openssl pkcs8 -in key.pem -topk8 -nocrypt -outform DER -out key.der
> >
> > # add key
> > PRIV_KEY_ID=`cat key.der | keyctl padd asymmetric test_priv_key @s`
> > echo "priv key id = "$PRIV_KEY_ID PUB_KEY_ID=`cat cert.der | keyctl
> > padd asymmetric test_pub_key @s` echo "pub key id = "$PUB_KEY_ID
> >
> > # query key
> > keyctl pkey_query $PRIV_KEY_ID 0
> > keyctl pkey_query $PUB_KEY_ID 0
> >
> > # here we only run pkey_encrypt becasuse it is the fastest interface
> > function bench_pub() {
> > keyctl pkey_encrypt $PUB_KEY_ID 0 /tmp/data
> enc=pkcs1 >/tmp/enc.pub }
> >
> > # do bench_pub in loop to obtain the memory leak for (( i = 0; i <
> > ${LOOP_TIMES}; ++i )); do
> > bench_pub
> > done
> >
> > Signed-off-by: lei he <[email protected]>
>
> trash below pls drop.
>
>
> > # Please enter the commit message for your changes. Lines starting #
> > with '#' will be kept; you may remove them yourself if you want to.
> > # An empty message aborts the commit.
> > #
> > # Date: Tue Aug 16 11:53:30 2022 +0800
> > #
> > # On branch master
> > # Your branch is ahead of 'origin/master' by 1 commit.
> > # (use "git push" to publish your local commits)
> > #
> > # Changes to be committed:
> > # modified: drivers/crypto/virtio/virtio_crypto_akcipher_algs.c
> > #
> > # Untracked files:
> > # cert.der
> > # key.der
> > # key.pem
> > #
> >
> > # Please enter the commit message for your changes. Lines starting #
> > with '#' will be kept; you may remove them yourself if you want to.
> > # An empty message aborts the commit.
> > #
> > # Date: Tue Aug 16 11:53:30 2022 +0800
> > #
> > # On branch master
> > # Your branch is ahead of 'origin/master' by 1 commit.
> > # (use "git push" to publish your local commits)
> > #
> > # Changes to be committed:
> > # modified: drivers/crypto/virtio/virtio_crypto_akcipher_algs.c
> > #
> > # Untracked files:
> > # cert.der
> > # key.der
> > # key.pem
> > #
> >
> > # Please enter the commit message for your changes. Lines starting #
> > with '#' will be kept; you may remove them yourself if you want to.
> > # An empty message aborts the commit.
> > #
> > # Date: Tue Aug 16 11:53:30 2022 +0800
> > #
> > # On branch master
> > # Your branch is ahead of 'origin/master' by 1 commit.
> > # (use "git push" to publish your local commits)
> > #
> > # Changes to be committed:
> > # modified: drivers/crypto/virtio/virtio_crypto_akcipher_algs.c
> > #
> > # Untracked files:
> > # cert.der
> > # key.der
> > # key.pem
> > #
> > ---
>
> with commit log fixed:
>
> Acked-by: Michael S. Tsirkin <[email protected]>
>
> > drivers/crypto/virtio/virtio_crypto_akcipher_algs.c | 4 ++++
> > 1 file changed, 4 insertions(+)
> >
> > diff --git a/drivers/crypto/virtio/virtio_crypto_akcipher_algs.c
> > b/drivers/crypto/virtio/virtio_crypto_akcipher_algs.c
> > index 2a60d0525cde..168195672e2e 100644
> > --- a/drivers/crypto/virtio/virtio_crypto_akcipher_algs.c
> > +++ b/drivers/crypto/virtio/virtio_crypto_akcipher_algs.c
> > @@ -56,6 +56,10 @@ static void virtio_crypto_akcipher_finalize_req(
> > struct virtio_crypto_akcipher_request *vc_akcipher_req,
> > struct akcipher_request *req, int err) {
> > + kfree(vc_akcipher_req->src_buf);
> > + kfree(vc_akcipher_req->dst_buf);
> > + vc_akcipher_req->src_buf = NULL;
> > + vc_akcipher_req->dst_buf = NULL;
> > virtcrypto_clear_request(&vc_akcipher_req->base);
> >
> >
> > crypto_finalize_akcipher_request(vc_akcipher_req->base.dataq->engine,
> > req, err);
> > --
> > 2.20.1