On Wed, Jul 06, 2022 at 12:27:49PM +0300, Péter Ujfalusi wrote: > > > On 06/07/2022 10:25, Dan Carpenter wrote: > > The tokenize_input() function is cleaner if it uses strndup_user() > > instead of simple_write_to_buffer(). The way it's written now, if > > *ppos is non-zero then it returns -EIO but normally we would return > > 0 in that case. It's easier to handle that in the callers. > > This patch breaks the probe point settings: > > # echo 52,1,0 > /sys/kernel/debug/sof/probe_points > -bash: echo: write error: Invalid argument > > I did not looked for the exact reason, but something is not correct. > Crud... Thanks for testing. I used strndup_user() in a couple other patches today and I didn't realize how strict it was. I've NAKed my patches which used strndup_user(). One of the patches was an infoleak patch so I'm going to resend that using memdup_user() instead but let's just drop this one. I guess another safer option would be to just always zero the buffers going into simple_write_to_buffer()... regards, dan carpenter
