diff options
authorElias Vanderstuyft <elias.vds@gmail.com>2014-03-29 12:08:45 -0700
committerDmitry Torokhov <dmitry.torokhov@gmail.com>2014-03-29 12:13:09 -0700
commitfc7392aa1b20debc7f398acc39ffc817630f11e6 (patch)
parent8a0435d958fb36d93b8df610124a0e91e5675c82 (diff)
Input: don't modify the id of ioctl-provided ff effect on upload failure
If a new (id == -1) ff effect was uploaded from userspace, ff-core.c::input_ff_upload() will have assigned a positive number to the new effect id. Currently, evdev.c::evdev_do_ioctl() will save this new id to userspace, regardless of whether the upload succeeded or not. On upload failure, this can be confusing because the dev->ff->effects[] array will not contain an element at the index of that new effect id. This patch fixes this by leaving the id unchanged after upload fails. Note: Unfortunately applications should still expect changed effect id for quite some time. This has been discussed on: http://www.mail-archive.com/linux-input@vger.kernel.org/msg08513.html ("ff-core effect id handling in case of a failed effect upload") Suggested-by: Dmitry Torokhov <dmitry.torokhov@gmail.com> Signed-off-by: Elias Vanderstuyft <elias.vds@gmail.com> Signed-off-by: Dmitry Torokhov <dmitry.torokhov@gmail.com>
1 files changed, 3 insertions, 1 deletions
diff --git a/drivers/input/evdev.c b/drivers/input/evdev.c
index a06e12552886..ce953d895f5b 100644
--- a/drivers/input/evdev.c
+++ b/drivers/input/evdev.c
@@ -954,11 +954,13 @@ static long evdev_do_ioctl(struct file *file, unsigned int cmd,
return -EFAULT;
error = input_ff_upload(dev, &effect, file);
+ if (error)
+ return error;
if (put_user(effect.id, &(((struct ff_effect __user *)p)->id)))
return -EFAULT;
- return error;
+ return 0;
/* Multi-number variable-length handlers */