On Wed, Jun 03, 2020 at 04:56:59PM -0700, Sargun Dhillon wrote: > On Wed, Jun 3, 2020 at 4:42 PM Kees Cook <keescook@xxxxxxxxxxxx> wrote: > > > > On Tue, Jun 02, 2020 at 06:10:40PM -0700, Sargun Dhillon wrote: > > > Sargun Dhillon (4): > > > fs, net: Standardize on file_receive helper to move fds across > > > processes > > > pid: Use file_receive helper to copy FDs > > > > The fixes (that should add open-coded cgroups stuff) should be separate > > patches so they can be backported. > Patch 1/4, and 2/4 are separated so they can be backported. Patch 1 should > go into long term, and patch 2 should land in stable. > > Do you see anything in 1/4, and 2/4 that shouldn't be there? So, my thinking was to open code the fixes to minimize the code churn in the -stable trees and isolate logical changes. However, in looking at the commits (3.6, 3.8) and the age of the rest of the nearby code in SCM_RIGHTS (3.7), and the actual oldest supported kernel release (3.16), I guess it would be better to split it like you've done. > > The helper doesn't take the __user pointer I thought we'd agreed it > > should to avoid changing any SCM_RIGHTS behaviors? > > > It doesn't change the SCM_RIGHTS behaviour because it continues > to have the logic which allocates the file descriptor outside of the > helper. > 1. Allocate FD (this happens in scm.c) > 2. Copy FD # to userspace (this happens in scm.c) > 3. Receive FD (this happens in the new helper) Sorry, I was not writing very clearly: I was meaning to have said: I was expecting the helper to take the __user pointer (like I thought we agreed[1]) so we could both avoid changing SCM_RIGHTS behavior and avoid copy/pasting of the get_unused/put_unused code in 3 places. (I get into this more in the other thread[2]). So, let's finalize this decision in the thread at [2]. Again, sorry I wasted your time due to my confusion! -Kees [1] Apologies, I misread your "1" in [3] to be "suggestion 1" from the quoted text from me in that email, rather than the "[1]" it was, which was a link to your counter-proposal. And then I wasted your time by saying "agreed". [2] https://lore.kernel.org/lkml/202006031845.F587F85A@keescook/ [3] https://lore.kernel.org/lkml/20200530011054.GA14852@ircssh-2.c.rugged-nimbus-611.internal/ -- Kees Cook _______________________________________________ Containers mailing list Containers@xxxxxxxxxxxxxxxxxxxxxxxxxx https://lists.linuxfoundation.org/mailman/listinfo/containers