diff options
| author |   Trent Piepho <xyzzy@speakeasy.org> | 2006-03-30 15:53:32 -0300 |
|---|---|---|
| committer |   Mauro Carvalho Chehab <mchehab@infradead.org> | 2006-04-02 04:56:01 -0300 |
| commit | 5e85bd057f0cb29881e3d55d29f48bb55bd2f450 (patch) | |
| tree | 7d1e582b25710d70487d1dc59e150b387a58c919 /drivers | |
| parent | V4L/DVB (3671): New module parameter 'tv_standard' (dvb-ttpci driver) (diff) | |
| download | linux-dev-5e85bd057f0cb29881e3d55d29f48bb55bd2f450.tar.xz linux-dev-5e85bd057f0cb29881e3d55d29f48bb55bd2f450.zip | |
V4L/DVB (3672): Fix memory leak in dvr open
The dvr device could be opened multiple times simultaneously in O_RDONLY mode.
Each open after the first would allocate a new dvr buffer (1880 KB) and leak
the old buffer. The first close would de-allocate the dvr buffer and cause
all other open dvrs to stop working. This patch allows only a single O_RDONLY
open of the drv device, as per the API specification. Multiple O_WRONLY opens
are still allowed and don't appear to cause any problems.
Signed-off-by: Trent Piepho <xyzzy@speakeasy.org>
Signed-off-by: Andrew de Quincey <adq_dvb@lidskialf.net>
Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
Diffstat (limited to 'drivers')
| -rw-r--r-- | drivers/media/dvb/dvb-core/dmxdev.c | 12 |
1 files changed, 9 insertions, 3 deletions
diff --git a/drivers/media/dvb/dvb-core/dmxdev.c b/drivers/media/dvb/dvb-core/dmxdev.c index 09e96e9ddbdf..04578df3f249 100644 --- a/drivers/media/dvb/dvb-core/dmxdev.c +++ b/drivers/media/dvb/dvb-core/dmxdev.c @@ -141,12 +141,18 @@ static int dvb_dvr_open(struct inode *inode, struct file *file) } if ((file->f_flags & O_ACCMODE) == O_RDONLY) { - void *mem = vmalloc(DVR_BUFFER_SIZE); + void *mem; + if (!dvbdev->readers) { + mutex_unlock(&dmxdev->mutex); + return -EBUSY; + } + mem = vmalloc(DVR_BUFFER_SIZE); if (!mem) { mutex_unlock(&dmxdev->mutex); return -ENOMEM; } dvb_ringbuffer_init(&dmxdev->dvr_buffer, mem, DVR_BUFFER_SIZE); + dvbdev->readers--; } if ((file->f_flags & O_ACCMODE) == O_WRONLY) { @@ -184,6 +190,7 @@ static int dvb_dvr_release(struct inode *inode, struct file *file) dmxdev->dvr_orig_fe); } if ((file->f_flags & O_ACCMODE) == O_RDONLY) { + dvbdev->readers++; if (dmxdev->dvr_buffer.data) { void *mem = dmxdev->dvr_buffer.data; mb(); @@ -1029,8 +1036,7 @@ static struct file_operations dvb_dvr_fops = { static struct dvb_device dvbdev_dvr = { .priv = NULL, - .users = 1, - .writers = 1, + .readers = 1, .fops = &dvb_dvr_fops }; |