On Sun, 07 Aug 2016 11:48:42 +0200, Takashi Sakamoto wrote:
In a 32/64 bit compatibility layer of ALSA sequencer core, data for some ioctls is copied to kernel stack and passed to core operations. Then, address limit of running task is changed because core implementation expected arguments in userspace.
In this case, snd_seq_kernel_client_ctl() is available. This commit replaces with it.
Signed-off-by: Takashi Sakamoto o-takashi@sakamocchi.jp
sound/core/seq/seq_compat.c | 25 +++++++++++++------------ 1 file changed, 13 insertions(+), 12 deletions(-)
diff --git a/sound/core/seq/seq_compat.c b/sound/core/seq/seq_compat.c index 70d3ddb..6cc7302 100644 --- a/sound/core/seq/seq_compat.c +++ b/sound/core/seq/seq_compat.c @@ -42,13 +42,11 @@ struct snd_seq_port_info32 { char reserved[59]; /* for future use */ };
-static int seq_call_port_info_ioctl(struct snd_seq_client *client,
unsigned int cmd,+static int seq_call_port_info_ioctl(int clientid, unsigned int cmd, struct snd_seq_port_info32 __user *data32) { int err = -EFAULT; struct snd_seq_port_info *data;
mm_segment_t fs;
data = kmalloc(sizeof(*data), GFP_KERNEL); if (!data)
@@ -60,9 +58,7 @@ static int seq_call_port_info_ioctl(struct snd_seq_client *client, goto error; data->kernel = NULL;
- fs = snd_enter_user();
- err = seq_do_ioctl(client, cmd, data);
- snd_leave_user(fs);
- err = snd_seq_kernel_client_ctl(clientid, cmd, data); if (err < 0) goto error;
It's better to pass a snd_seq_client pointer to this function and evaluate client->port in the function instead of referencing to client->port from each caller.
Takashi