diff options
| author |   Mauro Carvalho Chehab <m.chehab@samsung.com> | 2014-09-03 20:44:04 -0300 |
|---|---|---|
| committer | Mauro Carvalho Chehab <m.chehab@samsung.com> | 2014-09-08 10:00:52 -0300 |
| commit | 04da2daee383391954b34e7d0fe0281d75447d61 (patch) | |
| tree | bd5e08c06fb73f2fda5f4199b00b91ecefc8d9d4 | |
| parent | [media] tw68: make tw68_pci_tbl static and constify (diff) | |
| download | linux-dev-04da2daee383391954b34e7d0fe0281d75447d61.tar.xz linux-dev-04da2daee383391954b34e7d0fe0281d75447d61.zip | |
[media] ngene: properly handle __user ptr
Sparse is complaining about ngene's bad usage of a __user ptr:
>> drivers/media/pci/ngene/ngene-dvb.c:62:48: sparse: incorrect type in argument 2 (different address spaces)
drivers/media/pci/ngene/ngene-dvb.c:62:48: expected unsigned char const [usertype] *buf
drivers/media/pci/ngene/ngene-dvb.c:62:48: got char const [noderef] <asn:1>*buf
As this is intercepting a .write() file ops, we can't just memcpy. We need to use
copy_from_user.
Reported-by: kbuild test robot <fengguang.wu@intel.com>
Signed-off-by: Mauro Carvalho Chehab <m.chehab@samsung.com>
| -rw-r--r-- | drivers/media/dvb-core/dvb_ringbuffer.c | 26 | ||||
| -rw-r--r-- | drivers/media/dvb-core/dvb_ringbuffer.h | 2 | ||||
| -rw-r--r-- | drivers/media/pci/ngene/ngene-dvb.c | 2 |
3 files changed, 29 insertions, 1 deletions
diff --git a/drivers/media/dvb-core/dvb_ringbuffer.c b/drivers/media/dvb-core/dvb_ringbuffer.c index a5712cd7c65f..1100e98a7b1d 100644 --- a/drivers/media/dvb-core/dvb_ringbuffer.c +++ b/drivers/media/dvb-core/dvb_ringbuffer.c @@ -166,6 +166,31 @@ ssize_t dvb_ringbuffer_write(struct dvb_ringbuffer *rbuf, const u8 *buf, size_t return len; } +ssize_t dvb_ringbuffer_write_user(struct dvb_ringbuffer *rbuf, + const u8 __user *buf, size_t len) +{ + int status; + size_t todo = len; + size_t split; + + split = (rbuf->pwrite + len > rbuf->size) ? rbuf->size - rbuf->pwrite : 0; + + if (split > 0) { + status = copy_from_user(rbuf->data+rbuf->pwrite, buf, split); + if (status) + return len - todo; + buf += split; + todo -= split; + rbuf->pwrite = 0; + } + status = copy_from_user(rbuf->data+rbuf->pwrite, buf, todo); + if (status) + return len - todo; + rbuf->pwrite = (rbuf->pwrite + todo) % rbuf->size; + + return len; +} + ssize_t dvb_ringbuffer_pkt_write(struct dvb_ringbuffer *rbuf, u8* buf, size_t len) { int status; @@ -297,3 +322,4 @@ EXPORT_SYMBOL(dvb_ringbuffer_flush_spinlock_wakeup); EXPORT_SYMBOL(dvb_ringbuffer_read_user); EXPORT_SYMBOL(dvb_ringbuffer_read); EXPORT_SYMBOL(dvb_ringbuffer_write); +EXPORT_SYMBOL(dvb_ringbuffer_write_user); diff --git a/drivers/media/dvb-core/dvb_ringbuffer.h b/drivers/media/dvb-core/dvb_ringbuffer.h index 41f04dae69b6..9e1e11b7c39c 100644 --- a/drivers/media/dvb-core/dvb_ringbuffer.h +++ b/drivers/media/dvb-core/dvb_ringbuffer.h @@ -133,6 +133,8 @@ extern void dvb_ringbuffer_read(struct dvb_ringbuffer *rbuf, */ extern ssize_t dvb_ringbuffer_write(struct dvb_ringbuffer *rbuf, const u8 *buf, size_t len); +extern ssize_t dvb_ringbuffer_write_user(struct dvb_ringbuffer *rbuf, + const u8 __user *buf, size_t len); /** diff --git a/drivers/media/pci/ngene/ngene-dvb.c b/drivers/media/pci/ngene/ngene-dvb.c index a8a4045f66d7..59bb2858c8d0 100644 --- a/drivers/media/pci/ngene/ngene-dvb.c +++ b/drivers/media/pci/ngene/ngene-dvb.c @@ -59,7 +59,7 @@ static ssize_t ts_write(struct file *file, const char __user *buf, (&dev->tsout_rbuf) >= count) < 0) return 0; - dvb_ringbuffer_write(&dev->tsout_rbuf, buf, count); + dvb_ringbuffer_write_user(&dev->tsout_rbuf, buf, count); return count; } |