On Tue, Jan 07, 2020 at 09:54:49PM +0100, Christian Brauner wrote: > On Tue, Jan 07, 2020 at 09:59:23AM -0800, Sargun Dhillon wrote: > > This patchset introduces a mechanism (pidfd_getfd syscall) to get file > > descriptors from other processes via pidfd. Although this can be achieved > > using SCM_RIGHTS, and parasitic code injection, this offers a more > > straightforward mechanism, with less overhead and complexity. The process > > under manipulation's fd still remains valid, and unmodified by the > > copy operation. > > > > It introduces a flags field. The flags field is reserved a the moment, > > but the intent is to extend it with the following capabilities: > > * Close the remote FD when copying it > > * Drop the cgroup data if it's a fd pointing a socket when copying it > > > > The syscall numbers were chosen to be one greater than openat2. > > > > Summary of history: > > This initially started as a ptrace command. It did not require the process > > to be stopped, and felt like kind of an awkward fit for ptrace. After that, > > it moved to an ioctl on the pidfd. Given the core functionality, it made > > sense to make it a syscall which did not require the process to be stopped. > > > > Previous versions: > > V8: https://lore.kernel.org/lkml/20200103162928.5271-1-sargun@xxxxxxxxx/ > > V7: https://lore.kernel.org/lkml/20191226180227.GA29389@ircssh-2.c.rugged-nimbus-611.internal/ > > V6: https://lore.kernel.org/lkml/20191223210823.GA25083@ircssh-2.c.rugged-nimbus-611.internal/ > > V5: https://lore.kernel.org/lkml/20191220232746.GA20215@ircssh-2.c.rugged-nimbus-611.internal/ > > V4: https://lore.kernel.org/lkml/20191218235310.GA17259@ircssh-2.c.rugged-nimbus-611.internal/ > > V3: https://lore.kernel.org/lkml/20191217005842.GA14379@ircssh-2.c.rugged-nimbus-611.internal/ > > V2: https://lore.kernel.org/lkml/20191209070446.GA32336@ircssh-2.c.rugged-nimbus-611.internal/ > > RFC V1: https://lore.kernel.org/lkml/20191205234450.GA26369@ircssh-2.c.rugged-nimbus-611.internal/ > > I don't see anything wrong with this series anymore: > > Acked-by: Christian Brauner <christian.brauner@xxxxxxxxxx> > > Other Acked-bys/Reviewed-bys and reviews of course strongly encouraged! > Christian Fyi, I'm waiting a few days on a reply from Al. Depending on his input the intent rn is to move this into my for-next early next week. Christian
