From 6fefad49f71552d0336a2d1095b50858f1c95023 Mon Sep 17 00:00:00 2001 From: Frank Mori Hess Date: Wed, 21 Jul 2004 00:10:59 +0000 Subject: [PATCH] fix double-munging when bufinfo ioctl is called in concert with read()s from /dev/comediX --- comedi/comedi_fops.c | 3 +-- comedi/drivers.c | 9 ++++++--- 2 files changed, 7 insertions(+), 5 deletions(-) diff --git a/comedi/comedi_fops.c b/comedi/comedi_fops.c index 79fec01a..92d0a825 100644 --- a/comedi/comedi_fops.c +++ b/comedi/comedi_fops.c @@ -1504,8 +1504,7 @@ static ssize_t comedi_read_v22(struct file * file,char *buf,size_t nbytes,loff_t schedule(); continue; } - - comedi_buf_munge(dev, s, n); + comedi_buf_munge(dev, s, async->buf_write_count - async->munge_count); m = copy_to_user(buf, async->prealloc_buf + async->buf_read_ptr, n); if(m){ diff --git a/comedi/drivers.c b/comedi/drivers.c index 527e711f..045ad0cc 100644 --- a/comedi/drivers.c +++ b/comedi/drivers.c @@ -120,7 +120,6 @@ int comedi_device_attach(comedi_device *dev,comedi_devconfig *it) spin_lock_init(&dev->spinlock); dev->minor=minor; dev->use_count = use_count; - for(driv=comedi_drivers;driv;driv=driv->next){ if(!try_module_get( driv->module )) { @@ -480,14 +479,18 @@ unsigned int comedi_buf_munge( comedi_device *dev, comedi_subdevice *s, if( s->munge == NULL || ( s->async->cmd.flags & CMDF_RAWDATA ) ) return count; - /* don't munge partial samples */ num_bytes -= num_bytes % bytes_per_sample(s); while( count < num_bytes ) { - unsigned int block_size; + int block_size; block_size = num_bytes - count; + if(block_size < 0) + { + rt_printk("%s: %s: bug! block_size is negative\n", __FILE__, __FUNCTION__); + break; + } if( (int)(s->async->munge_ptr + block_size - s->async->prealloc_bufsz) > 0 ) block_size = s->async->prealloc_bufsz - s->async->munge_ptr; -- 2.26.2