From 6e4129f8163460c79bb99887bc6f791196fcbda2 Mon Sep 17 00:00:00 2001 From: Fuqian Huang Date: Wed, 3 Jul 2019 13:28:37 -0300 Subject: media: media/dvb: Use kmemdup rather than duplicating its implementation [ Upstream commit f6af820ef1be58c2e4b81aa479b9f109eb6344ce ] kmemdup is introduced to duplicate a region of memory in a neat way. Rather than kmalloc/kzalloc + memcpy, which the programmer needs to write the size twice (sometimes lead to mistakes), kmemdup improves readability, leads to smaller code and also reduce the chances of mistakes. Suggestion to use kmemdup rather than using kmalloc/kzalloc + memcpy. Signed-off-by: Fuqian Huang Signed-off-by: Sean Young Signed-off-by: Mauro Carvalho Chehab Stable-dep-of: 8c64f4cdf4e6 ("media: edia: dvbdev: fix a use-after-free") Signed-off-by: Sasha Levin --- drivers/media/dvb-core/dvbdev.c | 3 +-- drivers/media/dvb-frontends/drx39xyj/drxj.c | 5 ++--- 2 files changed, 3 insertions(+), 5 deletions(-) diff --git a/drivers/media/dvb-core/dvbdev.c b/drivers/media/dvb-core/dvbdev.c index 1f80c4fa31c9..5d68ad0ac5d2 100644 --- a/drivers/media/dvb-core/dvbdev.c +++ b/drivers/media/dvb-core/dvbdev.c @@ -485,7 +485,7 @@ int dvb_register_device(struct dvb_adapter *adap, struct dvb_device **pdvbdev, return -ENOMEM; } - dvbdevfops = kzalloc(sizeof(struct file_operations), GFP_KERNEL); + dvbdevfops = kmemdup(template->fops, sizeof(*dvbdevfops), GFP_KERNEL); if (!dvbdevfops){ kfree (dvbdev); @@ -502,7 +502,6 @@ int dvb_register_device(struct dvb_adapter *adap, struct dvb_device **pdvbdev, dvbdev->fops = dvbdevfops; init_waitqueue_head (&dvbdev->wait_queue); - memcpy(dvbdevfops, template->fops, sizeof(struct file_operations)); dvbdevfops->owner = adap->module; list_add_tail (&dvbdev->list_head, &adap->device_list); diff --git a/drivers/media/dvb-frontends/drx39xyj/drxj.c b/drivers/media/dvb-frontends/drx39xyj/drxj.c index 9670bc98b45a..33cf6dccb547 100644 --- a/drivers/media/dvb-frontends/drx39xyj/drxj.c +++ b/drivers/media/dvb-frontends/drx39xyj/drxj.c @@ -12287,7 +12287,8 @@ struct dvb_frontend *drx39xxj_attach(struct i2c_adapter *i2c) if (state == NULL) goto error; - demod = kmalloc(sizeof(struct drx_demod_instance), GFP_KERNEL); + demod = kmemdup(&drxj_default_demod_g, + sizeof(struct drx_demod_instance), GFP_KERNEL); if (demod == NULL) goto error; @@ -12311,8 +12312,6 @@ struct dvb_frontend *drx39xxj_attach(struct i2c_adapter *i2c) state->demod = demod; /* setup the demod data */ - memcpy(demod, &drxj_default_demod_g, sizeof(struct drx_demod_instance)); - demod->my_i2c_dev_addr = demod_addr; demod->my_common_attr = demod_comm_attr; demod->my_i2c_dev_addr->user_data = state; -- cgit v1.2.3