3.16.39-rc1 review patch. If anyone has any objections, please let me know.
------------------ From: Mauro Carvalho Chehab <[email protected]> commit 04da2daee383391954b34e7d0fe0281d75447d61 upstream. 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 <[email protected]> Signed-off-by: Mauro Carvalho Chehab <[email protected]> Signed-off-by: Ben Hutchings <[email protected]> --- drivers/media/dvb-core/dvb_ringbuffer.c | 26 ++++++++++++++++++++++++++ drivers/media/dvb-core/dvb_ringbuffer.h | 2 ++ drivers/media/pci/ngene/ngene-dvb.c | 2 +- 3 files changed, 29 insertions(+), 1 deletion(-) --- 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_ 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_spinl EXPORT_SYMBOL(dvb_ringbuffer_read_user); EXPORT_SYMBOL(dvb_ringbuffer_read); EXPORT_SYMBOL(dvb_ringbuffer_write); +EXPORT_SYMBOL(dvb_ringbuffer_write_user); --- 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 d */ 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); /** --- 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 *fil (&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; }
