Re: [PATCH] rust_binder: check context manager before creating node
From: Greg Kroah-Hartman
Date: Thu Jun 18 2026 - 07:30:08 EST
A: http://en.wikipedia.org/wiki/Top_post
Q: Were do I find info about this thing called top-posting?
A: Because it messes up the order in which people normally read text.
Q: Why is top-posting such a bad thing?
A: Top-posting.
Q: What is the most annoying thing in e-mail?
A: No.
Q: Should I include quotations after my reply?
http://daringfireball.net/2007/07/on_top
On Thu, Jun 18, 2026 at 04:49:31PM +0530, Keshav Verma wrote:
> Thanks, I will fix the line wrapping and add the appropriate Fixes tag in
> v2.
Also, you sent html email which the lists reject :(
> This can be triggered after the normal context manager has already been
> registered. A second process can open /dev/binder and call
> BINDER_SET_CONTEXT_MGR_EXT with a local BINDER_TYPE_BINDER object. The
> ioctl returns -EBUSY because the context manager already exists.
>
> Repeating this with unique ptr/cookie values triggers the warning each time.
>
> Since this is easy to trigger from userspace, should I drop the pr_warn!() from
> the check in v2 and just return -EBUSY there?
If userspace can trigger this, then please remove it so that it doesn't
cause a denial-of-service on the kernel log.
thanks,
greg k-h