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Tsirkin" , Jason Wang , Xuan Zhuo , Nathan Chancellor , virtualization@lists.linux.dev, lei he , Herbert Xu , =?UTF-8?Q?Eugenio_P=C3=A9rez?= , "David S. Miller" References: <80b91321-138c-41de-95c7-47c3be07fe76@web.de> Content-Language: en-US From: zhenwei pi In-Reply-To: <80b91321-138c-41de-95c7-47c3be07fe76@web.de> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit On 10/12/24 16:06, Markus Elfring wrote: > From: Markus Elfring > Date: Sat, 12 Oct 2024 09:51:58 +0200 > > Move the reset of the data structure member “n” to a null pointer > into an if branch so that this assignment will be performed only after > a key parsing failure. > > Signed-off-by: Markus Elfring > --- > drivers/crypto/virtio/virtio_crypto_akcipher_algs.c | 5 +++-- > 1 file changed, 3 insertions(+), 2 deletions(-) > > diff --git a/drivers/crypto/virtio/virtio_crypto_akcipher_algs.c b/drivers/crypto/virtio/virtio_crypto_akcipher_algs.c > index 48fee07b7e51..56557d4778b0 100644 > --- a/drivers/crypto/virtio/virtio_crypto_akcipher_algs.c > +++ b/drivers/crypto/virtio/virtio_crypto_akcipher_algs.c > @@ -355,7 +355,6 @@ static int virtio_crypto_rsa_set_key(struct crypto_akcipher *tfm, > > /* mpi_free will test n, just free it. */ > mpi_free(rsa_ctx->n); > - rsa_ctx->n = NULL; > > if (private) { > keytype = VIRTIO_CRYPTO_AKCIPHER_KEY_TYPE_PRIVATE; > @@ -365,8 +364,10 @@ static int virtio_crypto_rsa_set_key(struct crypto_akcipher *tfm, > ret = rsa_parse_pub_key(&rsa_key, key, keylen); > } > > - if (ret) > + if (ret) { > + rsa_ctx->n = NULL; > return ret; > + } > > rsa_ctx->n = mpi_read_raw_data(rsa_key.n, rsa_key.n_sz); > if (!rsa_ctx->n) > -- Hi, This change only reduces a single assignment on a key parsing failure, however it breaks the original "free a pointer, and set it to NULL". I prefer the original style. Lei, what's your opinion? > 2.46.1 >