V4L/DVB (6305): V4L: videobuf-core.c avoid NULL dereferences in videobuf-core
The return value of videobuf_alloc() is unchecked but this function will
return NULL on an error. Check for NULL and make videobuf_reqbufs()
return the number of successfully allocated buffers.
Also, fix saa7146_video.c and bttv-driver.c to use this returned
buffer count.
Tested against the vivi driver. Not tested against saa7146 or bt8xx
devices.
Signed-off-by: Brandon Philips <bphilips@suse.de>
Signed-off-by: Mauro Carvalho Chehab <mchehab@infradead.org>
diff --git a/drivers/media/common/saa7146_video.c b/drivers/media/common/saa7146_video.c
index 29dbc60..f245a3b 100644
--- a/drivers/media/common/saa7146_video.c
+++ b/drivers/media/common/saa7146_video.c
@@ -1212,6 +1212,8 @@
mutex_unlock(&q->lock);
return err;
}
+
+ gbuffers = err;
memset(mbuf,0,sizeof(*mbuf));
mbuf->frames = gbuffers;
mbuf->size = gbuffers * gbufsize;
diff --git a/drivers/media/video/bt8xx/bttv-driver.c b/drivers/media/video/bt8xx/bttv-driver.c
index 4927853..7a332b3 100644
--- a/drivers/media/video/bt8xx/bttv-driver.c
+++ b/drivers/media/video/bt8xx/bttv-driver.c
@@ -3072,6 +3072,8 @@
V4L2_MEMORY_MMAP);
if (retval < 0)
goto fh_unlock_and_return;
+
+ gbuffers = retval;
memset(mbuf,0,sizeof(*mbuf));
mbuf->frames = gbuffers;
mbuf->size = gbuffers * gbufsize;
diff --git a/drivers/media/video/videobuf-core.c b/drivers/media/video/videobuf-core.c
index f5c5ea8..25a9849 100644
--- a/drivers/media/video/videobuf-core.c
+++ b/drivers/media/video/videobuf-core.c
@@ -329,7 +329,7 @@
goto done;
}
- req->count = count;
+ req->count = retval;
done:
mutex_unlock(&q->lock);
@@ -698,7 +698,7 @@
{
enum v4l2_field field;
unsigned long flags=0;
- int count = 0, size = 0;
+ unsigned int count = 0, size = 0;
int err, i;
q->ops->buf_setup(q,&count,&size);
@@ -709,9 +709,11 @@
size = PAGE_ALIGN(size);
err = videobuf_mmap_setup(q, count, size, V4L2_MEMORY_USERPTR);
- if (err)
+ if (err < 0)
return err;
+ count = err;
+
for (i = 0; i < count; i++) {
field = videobuf_next_field(q);
err = q->ops->buf_prepare(q,q->bufs[i],field);
@@ -876,6 +878,9 @@
for (i = 0; i < bcount; i++) {
q->bufs[i] = videobuf_alloc(q);
+ if (q->bufs[i] == NULL)
+ break;
+
q->bufs[i]->i = i;
q->bufs[i]->input = UNSET;
q->bufs[i]->memory = memory;
@@ -891,10 +896,13 @@
}
}
- dprintk(1,"mmap setup: %d buffers, %d bytes each\n",
- bcount,bsize);
+ if (!i)
+ return -ENOMEM;
- return 0;
+ dprintk(1,"mmap setup: %d buffers, %d bytes each\n",
+ i, bsize);
+
+ return i;
}
int videobuf_mmap_free(struct videobuf_queue *q)