From aa501be989f5df58c4732d5eb1989e5ca6479d90 Mon Sep 17 00:00:00 2001 From: Chris Pascoe Date: Mon, 19 Nov 2007 04:45:38 -0300 Subject: [PATCH] V4L/DVB (6636): xc2028: protect device list Protect refcount changes and modifications to xc2028_list with a mutex. Signed-off-by: Chris Pascoe Signed-off-by: Mauro Carvalho Chehab --- drivers/media/video/tuner-xc2028.c | 14 +++++++++++++- 1 file changed, 13 insertions(+), 1 deletion(-) diff --git a/drivers/media/video/tuner-xc2028.c b/drivers/media/video/tuner-xc2028.c index a01231a0410d..ac7f3e1d32f4 100644 --- a/drivers/media/video/tuner-xc2028.c +++ b/drivers/media/video/tuner-xc2028.c @@ -44,6 +44,8 @@ MODULE_PARM_DESC(audio_std, "NICAM/B\n"); static LIST_HEAD(xc2028_list); +static DEFINE_MUTEX(xc2028_list_mutex); + /* struct for storing firmware table */ struct firmware_description { unsigned int type; @@ -854,6 +856,8 @@ static int xc2028_dvb_release(struct dvb_frontend *fe) tuner_dbg("%s called\n", __FUNCTION__); + mutex_lock(&xc2028_list_mutex); + priv->count--; if (!priv->count) { @@ -865,6 +869,8 @@ static int xc2028_dvb_release(struct dvb_frontend *fe) kfree(priv); } + mutex_unlock(&xc2028_list_mutex); + return 0; } @@ -940,6 +946,8 @@ void *xc2028_attach(struct dvb_frontend *fe, struct xc2028_config *cfg) video_dev = cfg->video_dev; + mutex_lock(&xc2028_list_mutex); + list_for_each_entry(priv, &xc2028_list, xc2028_list) { if (priv->video_dev == cfg->video_dev) { video_dev = NULL; @@ -949,8 +957,10 @@ void *xc2028_attach(struct dvb_frontend *fe, struct xc2028_config *cfg) if (video_dev) { priv = kzalloc(sizeof(*priv), GFP_KERNEL); - if (priv == NULL) + if (priv == NULL) { + mutex_unlock(&xc2028_list_mutex); return NULL; + } priv->bandwidth = BANDWIDTH_6_MHZ; priv->need_load_generic = 1; @@ -974,6 +984,8 @@ void *xc2028_attach(struct dvb_frontend *fe, struct xc2028_config *cfg) tuner_info("type set to %s\n", "XCeive xc2028/xc3028 tuner"); + mutex_unlock(&xc2028_list_mutex); + return fe; } -- GitLab