From 27074efa2ee8c1ef07dc5f644104e35d39e43322 Mon Sep 17 00:00:00 2001 From: Hans de Goede Date: Thu, 30 Dec 2010 19:54:33 -0300 Subject: [media] gspca_main: Locking fixes 2 Before this patch vidioc_dqbuf is using its own read_lock, where as other queue related functions use queue_lock. This means that dqbuf is accessing several variables in a racy manor. The most important one being fr_o, which may be changed from underneath dqbuf by vidioc_reqbufs or vidioc_streamoff. Other variables which it accesses unprotected are gspca_dev->memory, gspca_dev->streaming and gspca_dev->capt_file. This patch fixes this by changing vidioc_dqbuf to also use the queue_lock. Signed-off-by: Hans de Goede Acked-by: Jean-Francois Moine Signed-off-by: Mauro Carvalho Chehab --- drivers/media/video/gspca/gspca.h | 1 - 1 file changed, 1 deletion(-) (limited to 'drivers/media/video/gspca/gspca.h') diff --git a/drivers/media/video/gspca/gspca.h b/drivers/media/video/gspca/gspca.h index 97b77a26a2eb..a2a1a6aa0606 100644 --- a/drivers/media/video/gspca/gspca.h +++ b/drivers/media/video/gspca/gspca.h @@ -205,7 +205,6 @@ struct gspca_dev { wait_queue_head_t wq; /* wait queue */ struct mutex usb_lock; /* usb exchange protection */ - struct mutex read_lock; /* read protection */ struct mutex queue_lock; /* ISOC queue protection */ int usb_err; /* USB error - protected by usb_lock */ u16 pkt_size; /* ISOC packet size */ -- cgit v1.2.1 From 7f6eb118df84715b128e25e99dc6a3ebc5b133d6 Mon Sep 17 00:00:00 2001 From: Hans de Goede Date: Thu, 30 Dec 2010 20:20:09 -0300 Subject: [media] gspca_main: Remove no longer used users variable Remove the no longer used / useful users variable, and with that gone there also is no longer a need to take queue_lock in dev_open. Signed-off-by: Hans de Goede Acked-by: Jean-Francois Moine Signed-off-by: Mauro Carvalho Chehab --- drivers/media/video/gspca/gspca.h | 1 - 1 file changed, 1 deletion(-) (limited to 'drivers/media/video/gspca/gspca.h') diff --git a/drivers/media/video/gspca/gspca.h b/drivers/media/video/gspca/gspca.h index a2a1a6aa0606..41755226d389 100644 --- a/drivers/media/video/gspca/gspca.h +++ b/drivers/media/video/gspca/gspca.h @@ -211,7 +211,6 @@ struct gspca_dev { #ifdef CONFIG_PM char frozen; /* suspend - resume */ #endif - char users; /* number of opens */ char present; /* device connected */ char nbufread; /* number of buffers for read() */ char memory; /* memory type (V4L2_MEMORY_xxx) */ -- cgit v1.2.1