Christoph Hellwig <hch@xxxxxx> writes: > On Fri, Apr 17, 2020 at 05:41:52PM -0500, Eric W. Biederman wrote: >> > this series gets rid of playing with the address limit in the exec and >> > coredump code. Most of this was fairly trivial, the biggest changes are >> > those to the spufs coredump code. >> > >> > Changes since v1: >> > - properly spell NUL >> > - properly handle the compat siginfo case in ELF coredumps >> >> Quick question is exec from a kernel thread within the scope of what you >> are looking at? >> >> There is a set_fs(USER_DS) in flush_old_exec whose sole purpose appears >> to be to allow exec from kernel threads. Where the kernel threads >> run with set_fs(KERNEL_DS) until they call exec. > > This series doesn't really look at that area. But I don't think exec > from a kernel thread makes any sense, and cleaning up how to set the > initial USER_DS vs KERNEL_DS state is something I'll eventually get to, > it seems like a major mess at the moment. Fair enough. I just wanted to make certain that it is on people's radar that when the kernel exec's init the arguments are read from kernel memory and the set_fs(USER_DS) in flush_old_exec() that makes that not work later. It is subtle and easy to miss. So I figured I would mention it since I have been staring at the exec code a lot lately. Eric
