linux/arch/csky/kernel
Linus Torvalds 1ec6574a3c This set of changes updates init and user mode helper tasks to be
ordinary user mode tasks.
 
 In commit 40966e316f ("kthread: Ensure struct kthread is present for
 all kthreads") caused init and the user mode helper threads that call
 kernel_execve to have struct kthread allocated for them.  This struct
 kthread going away during execve in turned made a use after free of
 struct kthread possible.
 
 The commit 343f4c49f2 ("kthread: Don't allocate kthread_struct for
 init and umh") is enough to fix the use after free and is simple enough
 to be backportable.
 
 The rest of the changes pass struct kernel_clone_args to clean things
 up and cause the code to make sense.
 
 In making init and the user mode helpers tasks purely user mode tasks
 I ran into two complications.  The function task_tick_numa was
 detecting tasks without an mm by testing for the presence of
 PF_KTHREAD.  The initramfs code in populate_initrd_image was using
 flush_delayed_fput to ensuere the closing of all it's file descriptors
 was complete, and flush_delayed_fput does not work in a userspace thread.
 
 I have looked and looked and more complications and in my code review
 I have not found any, and neither has anyone else with the code sitting
 in linux-next.
 
 Link: https://lkml.kernel.org/r/87mtfu4up3.fsf@email.froward.int.ebiederm.org
 
 Eric W. Biederman (8):
       kthread: Don't allocate kthread_struct for init and umh
       fork: Pass struct kernel_clone_args into copy_thread
       fork: Explicity test for idle tasks in copy_thread
       fork: Generalize PF_IO_WORKER handling
       init: Deal with the init process being a user mode process
       fork: Explicitly set PF_KTHREAD
       fork: Stop allowing kthreads to call execve
       sched: Update task_tick_numa to ignore tasks without an mm
 
  arch/alpha/kernel/process.c      | 13 ++++++------
  arch/arc/kernel/process.c        | 13 ++++++------
  arch/arm/kernel/process.c        | 12 ++++++-----
  arch/arm64/kernel/process.c      | 12 ++++++-----
  arch/csky/kernel/process.c       | 15 ++++++-------
  arch/h8300/kernel/process.c      | 10 ++++-----
  arch/hexagon/kernel/process.c    | 12 ++++++-----
  arch/ia64/kernel/process.c       | 15 +++++++------
  arch/m68k/kernel/process.c       | 12 ++++++-----
  arch/microblaze/kernel/process.c | 12 ++++++-----
  arch/mips/kernel/process.c       | 13 ++++++------
  arch/nios2/kernel/process.c      | 12 ++++++-----
  arch/openrisc/kernel/process.c   | 12 ++++++-----
  arch/parisc/kernel/process.c     | 18 +++++++++-------
  arch/powerpc/kernel/process.c    | 15 +++++++------
  arch/riscv/kernel/process.c      | 12 ++++++-----
  arch/s390/kernel/process.c       | 12 ++++++-----
  arch/sh/kernel/process_32.c      | 12 ++++++-----
  arch/sparc/kernel/process_32.c   | 12 ++++++-----
  arch/sparc/kernel/process_64.c   | 12 ++++++-----
  arch/um/kernel/process.c         | 15 +++++++------
  arch/x86/include/asm/fpu/sched.h |  2 +-
  arch/x86/include/asm/switch_to.h |  8 +++----
  arch/x86/kernel/fpu/core.c       |  4 ++--
  arch/x86/kernel/process.c        | 18 +++++++++-------
  arch/xtensa/kernel/process.c     | 17 ++++++++-------
  fs/exec.c                        |  8 ++++---
  include/linux/sched/task.h       |  8 +++++--
  init/initramfs.c                 |  2 ++
  init/main.c                      |  2 +-
  kernel/fork.c                    | 46 +++++++++++++++++++++++++++++++++-------
  kernel/sched/fair.c              |  2 +-
  kernel/umh.c                     |  6 +++---
  33 files changed, 234 insertions(+), 160 deletions(-)
 
 Signed-off-by: "Eric W. Biederman" <ebiederm@xmission.com>
 -----BEGIN PGP SIGNATURE-----
 
 iQIzBAABCgAdFiEEgjlraLDcwBA2B+6cC/v6Eiajj0AFAmKaR/MACgkQC/v6Eiaj
 j0Aayg/7Bx66872d9c6igkJ+MPCTuh+v9QKCGwiYEmiU4Q5sVAFB0HPJO27qC14u
 630X0RFNZTkPzNNEJNIW4kw6Dj8s8YRKf+FgQAVt4SzdRwT7eIPDjk1nGraopPJ3
 O04pjvuTmUyidyViRyFcf2ptx/pnkrwP8jUSc+bGTgfASAKAgAokqKE5ecjewbBc
 Y/EAkQ6QW7KxPjeSmpAHwI+t3BpBev9WEC4PbhRhsBCQFO2+PJiklvqdhVNBnIjv
 qUezll/1xv9UYgniB15Q4Nb722SmnWSU3r8as1eFPugzTHizKhufrrpyP+KMK1A0
 tdtEJNs5t2DZF7ZbGTFSPqJWmyTYLrghZdO+lOmnaSjHxK4Nda1d4NzbefJ0u+FE
 tutewowvHtBX6AFIbx+H3O+DOJM2IgNMf+ReQDU/TyNyVf3wBrTbsr9cLxypIJIp
 zze8npoLMlB7B4yxVo5ES5e63EXfi3iHl0L3/1EhoGwriRz1kWgVLUX/VZOUpscL
 RkJHsW6bT8sqxPWAA5kyWjEN+wNR2PxbXi8OE4arT0uJrEBMUgDCzydzOv5tJB00
 mSQdytxH9LVdsmxBKAOBp5X6WOLGA4yb1cZ6E/mEhlqXMpBDF1DaMfwbWqxSYi4q
 sp5zU3SBAW0qceiZSsWZXInfbjrcQXNV/DkDRDO9OmzEZP4m1j0=
 =x6fy
 -----END PGP SIGNATURE-----

Merge tag 'kthread-cleanups-for-v5.19' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace

Pull kthread updates from Eric Biederman:
 "This updates init and user mode helper tasks to be ordinary user mode
  tasks.

  Commit 40966e316f ("kthread: Ensure struct kthread is present for
  all kthreads") caused init and the user mode helper threads that call
  kernel_execve to have struct kthread allocated for them. This struct
  kthread going away during execve in turned made a use after free of
  struct kthread possible.

  Here, commit 343f4c49f2 ("kthread: Don't allocate kthread_struct for
  init and umh") is enough to fix the use after free and is simple
  enough to be backportable.

  The rest of the changes pass struct kernel_clone_args to clean things
  up and cause the code to make sense.

  In making init and the user mode helpers tasks purely user mode tasks
  I ran into two complications. The function task_tick_numa was
  detecting tasks without an mm by testing for the presence of
  PF_KTHREAD. The initramfs code in populate_initrd_image was using
  flush_delayed_fput to ensuere the closing of all it's file descriptors
  was complete, and flush_delayed_fput does not work in a userspace
  thread.

  I have looked and looked and more complications and in my code review
  I have not found any, and neither has anyone else with the code
  sitting in linux-next"

* tag 'kthread-cleanups-for-v5.19' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace:
  sched: Update task_tick_numa to ignore tasks without an mm
  fork: Stop allowing kthreads to call execve
  fork: Explicitly set PF_KTHREAD
  init: Deal with the init process being a user mode process
  fork: Generalize PF_IO_WORKER handling
  fork: Explicity test for idle tasks in copy_thread
  fork: Pass struct kernel_clone_args into copy_thread
  kthread: Don't allocate kthread_struct for init and umh
2022-06-03 16:03:05 -07:00
..
probes csky: patch_text: Fixup last cpu should be master 2022-04-07 15:35:57 +08:00
vdso csky: Add VDSO with GENERIC_GETTIMEOFDAY, GENERIC_TIME_VSYSCALL, HAVE_GENERIC_VDSO 2021-02-27 16:35:09 +08:00
asm-offsets.c uaccess: remove CONFIG_SET_FS 2022-02-25 09:36:06 +01:00
atomic.S csky: Remove prologue of page fault handler in entry.S 2021-01-12 09:52:40 +08:00
cpu-probe.c csky: Exception handling and mm-fault 2018-10-25 23:36:19 +08:00
entry.S irq: csky: perform irqentry in entry code 2021-10-26 10:13:27 +01:00
ftrace.c ftrace: Cleanup ftrace_dyn_arch_init() 2021-10-08 19:41:39 -04:00
head.S csky: Add memory layout 2.5G(user):1.5G(kernel) 2021-01-12 09:52:40 +08:00
io.c csky: optimize memcpy_{from,to}io() and memset_io() 2022-04-18 21:23:55 +08:00
irq.c irq: csky: perform irqentry in entry code 2021-10-26 10:13:27 +01:00
Makefile csky: optimize memcpy_{from,to}io() and memset_io() 2022-04-18 21:23:55 +08:00
module.c csky: fix typos in comments 2022-04-06 22:37:58 +08:00
perf_callchain.c uaccess: fix type mismatch warnings from access_ok() 2022-02-25 09:36:05 +01:00
perf_event.c csky: Add VDSO with GENERIC_GETTIMEOFDAY, GENERIC_TIME_VSYSCALL, HAVE_GENERIC_VDSO 2021-02-27 16:35:09 +08:00
perf_regs.c perf/arch: Remove perf_sample_data::regs_user_copy 2020-11-09 18:12:34 +01:00
power.c csky: Use do_kernel_power_off() 2022-05-19 19:30:30 +02:00
process.c This set of changes updates init and user mode helper tasks to be 2022-06-03 16:03:05 -07:00
ptrace.c ptrace: Create ptrace_report_syscall_{entry,exit} in ptrace.h 2022-03-10 13:35:08 -06:00
setup.c csky: convert to setup_initial_init_mm() 2021-07-08 11:48:21 -07:00
signal.c ptrace: Cleanups for v5.18 2022-03-28 17:29:53 -07:00
smp.c csky: Use of_get_cpu_hwid() 2021-10-20 13:37:24 -05:00
stacktrace.c sched: Add wrapper for get_wchan() to keep task blocked 2021-10-15 11:25:14 +02:00
syscall_table.c csky: System Call 2018-10-25 23:36:19 +08:00
syscall.c csky: System Call 2018-10-25 23:36:19 +08:00
time.c csky: Replace <linux/clk-provider.h> by <linux/of_clk.h> 2020-02-23 12:48:55 +08:00
traps.c Merge branch 'signal-for-v5.17' of git://git.kernel.org/pub/scm/linux/kernel/git/ebiederm/user-namespace 2022-01-17 05:49:30 +02:00
vdso.c csky: Add VDSO with GENERIC_GETTIMEOFDAY, GENERIC_TIME_VSYSCALL, HAVE_GENERIC_VDSO 2021-02-27 16:35:09 +08:00
vmlinux.lds.S csky: Add memory layout 2.5G(user):1.5G(kernel) 2021-01-12 09:52:40 +08:00