mm: Re-introduce vm_flags to do_mmap()

There was no more caller passing vm_flags to do_mmap(), and vm_flags was
removed from the function's input by:

commit 45e55300f114 ("mm: remove unnecessar

mm: Re-introduce vm_flags to do_mmap()

There was no more caller passing vm_flags to do_mmap(), and vm_flags was
removed from the function's input by:

commit 45e55300f114 ("mm: remove unnecessary wrapper function do_mmap_pgoff()").

There is a new user now. Shadow stack allocation passes VM_SHADOW_STACK to
do_mmap(). Thus, re-introduce vm_flags to do_mmap().

Co-developed-by: Rick Edgecombe <rick.p.edgecombe@intel.com>
Signed-off-by: Yu-cheng Yu <yu-cheng.yu@intel.com>
Signed-off-by: Rick Edgecombe <rick.p.edgecombe@intel.com>
Signed-off-by: Dave Hansen <dave.hansen@linux.intel.com>
Reviewed-by: Borislav Petkov (AMD) <bp@alien8.de>
Reviewed-by: Peter Collingbourne <pcc@google.com>
Reviewed-by: Kees Cook <keescook@chromium.org>
Reviewed-by: Kirill A. Shutemov <kirill.shutemov@linux.intel.com>
Reviewed-by: Mark Brown <broonie@kernel.org>
Acked-by: Mike Rapoport (IBM) <rppt@kernel.org>
Acked-by: David Hildenbrand <david@redhat.com>
Tested-by: Pengfei Xu <pengfei.xu@intel.com>
Tested-by: John Allen <john.allen@amd.com>
Tested-by: Kees Cook <keescook@chromium.org>
Tested-by: Mark Brown <broonie@kernel.org>
Link: https://lore.kernel.org/all/20230613001108.3040476-5-rick.p.edgecombe%40intel.com

show more ...

ipc/shm: introduce new do_vma_munmap() to munmap

The shm already has the vma iterator in position for a write.
do_vmi_munmap() searches for the correct position and aligns the write, so
it is not t

ipc/shm: introduce new do_vma_munmap() to munmap

The shm already has the vma iterator in position for a write.
do_vmi_munmap() searches for the correct position and aligns the write, so
it is not the right function to use in this case.

The shm VMA tree modification is similar to the brk munmap situation, the
vma iterator is in position and the VMA is already known. This patch
generalizes the brk munmap function do_brk_munmap() to be used for any
other callers with the vma iterator already in position to munmap a VMA.

Link: https://lkml.kernel.org/r/20230126212049.980501-1-Liam.Howlett@oracle.com
Signed-off-by: Liam R. Howlett <Liam.Howlett@oracle.com>
Reported-by: Sven Schnelle <svens@linux.ibm.com>
Link: https://lore.kernel.org/linux-mm/yt9dh6wec21a.fsf@linux.ibm.com/
Cc: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

show more ...

ipc/shm: use the vma iterator for munmap calls

Pass through the vma iterator to do_vmi_munmap() to handle the iterator
state internally

Link: https://lkml.kernel.org/r/20230120162650.984577-16-Liam

ipc/shm: use the vma iterator for munmap calls

Pass through the vma iterator to do_vmi_munmap() to handle the iterator
state internally

Link: https://lkml.kernel.org/r/20230120162650.984577-16-Liam.Howlett@oracle.com
Signed-off-by: Liam R. Howlett <Liam.Howlett@oracle.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

show more ...

ipc/shm: call underlying open/close vm_ops

Shared memory segments can be created that are backed by hugetlb pages.
When this happens, the vmas associated with any mappings (shmat) are
marked VM_HUG

ipc/shm: call underlying open/close vm_ops

Shared memory segments can be created that are backed by hugetlb pages.
When this happens, the vmas associated with any mappings (shmat) are
marked VM_HUGETLB, yet the vm_ops for such mappings are provided by
ipc/shm (shm_vm_ops). There is a mechanism to call the underlying hugetlb
vm_ops, and this is done for most operations. However, it is not done for
open and close.

This was not an issue until the introduction of the hugetlb vma_lock.
This lock structure is pointed to by vm_private_data and the open/close
vm_ops help maintain this structure. The special hugetlb routine called
at fork took care of structure updates at fork time. However,
vma_splitting is not properly handled for ipc shared memory mappings
backed by hugetlb pages. This can result in a "kernel NULL pointer
dereference" BUG or use after free as two vmas point to the same lock
structure.

Update the shm open and close routines to always call the underlying open
and close routines.

Link: https://lkml.kernel.org/r/20221114210018.49346-1-mike.kravetz@oracle.com
Fixes: 8d9bfb260814 ("hugetlb: add vma based lock for pmd sharing")
Signed-off-by: Mike Kravetz <mike.kravetz@oracle.com>
Reported-by: Doug Nelson <doug.nelson@intel.com>
Reported-by: <syzbot+83b4134621b7c326d950@syzkaller.appspotmail.com>
Cc: Alexander Mikhalitsyn <alexander.mikhalitsyn@virtuozzo.com>
Cc: "Eric W . Biederman" <ebiederm@xmission.com>
Cc: Manfred Spraul <manfred@colorfullife.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Miaohe Lin <linmiaohe@huawei.com>
Cc: Michal Hocko <mhocko@suse.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

show more ...

ipc/shm: use VMA iterator instead of linked list

The VMA iterator is faster than the linked llist, and it can be walked
even when VMAs are being removed from the address space, so there's no
need to

ipc/shm: use VMA iterator instead of linked list

The VMA iterator is faster than the linked llist, and it can be walked
even when VMAs are being removed from the address space, so there's no
need to keep track of 'next'.

Link: https://lkml.kernel.org/r/20220906194824.2110408-46-Liam.Howlett@oracle.com
Signed-off-by: Matthew Wilcox (Oracle) <willy@infradead.org>
Signed-off-by: Liam R. Howlett <Liam.Howlett@Oracle.com>
Tested-by: Yu Zhao <yuzhao@google.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: David Hildenbrand <david@redhat.com>
Cc: David Howells <dhowells@redhat.com>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Cc: SeongJae Park <sj@kernel.org>
Cc: Sven Schnelle <svens@linux.ibm.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Will Deacon <will@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

show more ...

shm: extend forced shm destroy to support objects from several IPC nses

Currently, the exit_shm() function not designed to work properly when
task->sysvshm.shm_clist holds shm objects from different

shm: extend forced shm destroy to support objects from several IPC nses

Currently, the exit_shm() function not designed to work properly when
task->sysvshm.shm_clist holds shm objects from different IPC namespaces.

This is a real pain when sysctl kernel.shm_rmid_forced = 1, because it
leads to use-after-free (reproducer exists).

This is an attempt to fix the problem by extending exit_shm mechanism to
handle shm's destroy from several IPC ns'es.

To achieve that we do several things:

1. add a namespace (non-refcounted) pointer to the struct shmid_kernel

2. during new shm object creation (newseg()/shmget syscall) we
initialize this pointer by current task IPC ns

3. exit_shm() fully reworked such that it traverses over all shp's in
task->sysvshm.shm_clist and gets IPC namespace not from current task
as it was before but from shp's object itself, then call
shm_destroy(shp, ns).

Note: We need to be really careful here, because as it was said before
(1), our pointer to IPC ns non-refcnt'ed. To be on the safe side we
using special helper get_ipc_ns_not_zero() which allows to get IPC ns
refcounter only if IPC ns not in the "state of destruction".

Q/A

Q: Why can we access shp->ns memory using non-refcounted pointer?
A: Because shp object lifetime is always shorther than IPC namespace
lifetime, so, if we get shp object from the task->sysvshm.shm_clist
while holding task_lock(task) nobody can steal our namespace.

Q: Does this patch change semantics of unshare/setns/clone syscalls?
A: No. It's just fixes non-covered case when process may leave IPC
namespace without getting task->sysvshm.shm_clist list cleaned up.

Link: https://lkml.kernel.org/r/67bb03e5-f79c-1815-e2bf-949c67047418@colorfullife.com
Link: https://lkml.kernel.org/r/20211109151501.4921-1-manfred@colorfullife.com
Fixes: ab602f79915 ("shm: make exit_shm work proportional to task activity")
Co-developed-by: Manfred Spraul <manfred@colorfullife.com>
Signed-off-by: Manfred Spraul <manfred@colorfullife.com>
Signed-off-by: Alexander Mikhalitsyn <alexander.mikhalitsyn@virtuozzo.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Cc: Greg KH <gregkh@linuxfoundation.org>
Cc: Andrei Vagin <avagin@gmail.com>
Cc: Pavel Tikhomirov <ptikhomirov@virtuozzo.com>
Cc: Vasily Averin <vvs@virtuozzo.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

show more ...

mm,hugetlb: remove mlock ulimit for SHM_HUGETLB

Commit 21a3c273f88c ("mm, hugetlb: add thread name and pid to
SHM_HUGETLB mlock rlimit warning") marked this as deprecated in 2012,
but it is not dele

mm,hugetlb: remove mlock ulimit for SHM_HUGETLB

Commit 21a3c273f88c ("mm, hugetlb: add thread name and pid to
SHM_HUGETLB mlock rlimit warning") marked this as deprecated in 2012,
but it is not deleted yet.

Mike says he still sees that message in log files on occasion, so maybe we
should preserve this warning.

Also remove hugetlbfs related user_shm_unlock in ipc/shm.c and remove the
user_shm_unlock after out.

Link: https://lkml.kernel.org/r/20211103105857.25041-1-zhangyiru3@huawei.com
Signed-off-by: zhangyiru <zhangyiru3@huawei.com>
Reviewed-by: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Liu Zixian <liuzixian4@huawei.com>
Cc: Michal Hocko <mhocko@suse.com>
Cc: wuxu.wu <wuxu.wu@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

show more ...

shm: extend forced shm destroy to support objects from several IPC nses

commit 85b6d24646e4125c591639841169baa98a2da503 upstream.

Currently, the exit_shm() function not designed to work properly wh

shm: extend forced shm destroy to support objects from several IPC nses

commit 85b6d24646e4125c591639841169baa98a2da503 upstream.

Currently, the exit_shm() function not designed to work properly when
task->sysvshm.shm_clist holds shm objects from different IPC namespaces.

This is a real pain when sysctl kernel.shm_rmid_forced = 1, because it
leads to use-after-free (reproducer exists).

This is an attempt to fix the problem by extending exit_shm mechanism to
handle shm's destroy from several IPC ns'es.

To achieve that we do several things:

1. add a namespace (non-refcounted) pointer to the struct shmid_kernel

2. during new shm object creation (newseg()/shmget syscall) we
initialize this pointer by current task IPC ns

3. exit_shm() fully reworked such that it traverses over all shp's in
task->sysvshm.shm_clist and gets IPC namespace not from current task
as it was before but from shp's object itself, then call
shm_destroy(shp, ns).

Note: We need to be really careful here, because as it was said before
(1), our pointer to IPC ns non-refcnt'ed. To be on the safe side we
using special helper get_ipc_ns_not_zero() which allows to get IPC ns
refcounter only if IPC ns not in the "state of destruction".

Q/A

Q: Why can we access shp->ns memory using non-refcounted pointer?
A: Because shp object lifetime is always shorther than IPC namespace
lifetime, so, if we get shp object from the task->sysvshm.shm_clist
while holding task_lock(task) nobody can steal our namespace.

Q: Does this patch change semantics of unshare/setns/clone syscalls?
A: No. It's just fixes non-covered case when process may leave IPC
namespace without getting task->sysvshm.shm_clist list cleaned up.

Link: https://lkml.kernel.org/r/67bb03e5-f79c-1815-e2bf-949c67047418@colorfullife.com
Link: https://lkml.kernel.org/r/20211109151501.4921-1-manfred@colorfullife.com
Fixes: ab602f79915 ("shm: make exit_shm work proportional to task activity")
Co-developed-by: Manfred Spraul <manfred@colorfullife.com>
Signed-off-by: Manfred Spraul <manfred@colorfullife.com>
Signed-off-by: Alexander Mikhalitsyn <alexander.mikhalitsyn@virtuozzo.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Cc: Greg KH <gregkh@linuxfoundation.org>
Cc: Andrei Vagin <avagin@gmail.com>
Cc: Pavel Tikhomirov <ptikhomirov@virtuozzo.com>
Cc: Vasily Averin <vvs@virtuozzo.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

show more ...

memcg: enable accounting of ipc resources

When user creates IPC objects it forces kernel to allocate memory for
these long-living objects.

It makes sense to account them to restrict the host's memo

memcg: enable accounting of ipc resources

When user creates IPC objects it forces kernel to allocate memory for
these long-living objects.

It makes sense to account them to restrict the host's memory consumption
from inside the memcg-limited container.

This patch enables accounting for IPC shared memory segments, messages
semaphores and semaphore's undo lists.

Link: https://lkml.kernel.org/r/d6507b06-4df6-78f8-6c54-3ae86e3b5339@virtuozzo.com
Signed-off-by: Vasily Averin <vvs@virtuozzo.com>
Reviewed-by: Shakeel Butt <shakeelb@google.com>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Alexey Dobriyan <adobriyan@gmail.com>
Cc: Andrei Vagin <avagin@gmail.com>
Cc: Borislav Petkov <bp@alien8.de>
Cc: Borislav Petkov <bp@suse.de>
Cc: Christian Brauner <christian.brauner@ubuntu.com>
Cc: Dmitry Safonov <0x7f454c46@gmail.com>
Cc: "Eric W. Biederman" <ebiederm@xmission.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: "J. Bruce Fields" <bfields@fieldses.org>
Cc: Jeff Layton <jlayton@kernel.org>
Cc: Jens Axboe <axboe@kernel.dk>
Cc: Jiri Slaby <jirislaby@kernel.org>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Kirill Tkhai <ktkhai@virtuozzo.com>
Cc: Michal Hocko <mhocko@kernel.org>
Cc: Oleg Nesterov <oleg@redhat.com>
Cc: Roman Gushchin <guro@fb.com>
Cc: Serge Hallyn <serge@hallyn.com>
Cc: Tejun Heo <tj@kernel.org>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vladimir Davydov <vdavydov.dev@gmail.com>
Cc: Yutian Yang <nglaive@gmail.com>
Cc: Zefan Li <lizefan.x@bytedance.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

show more ...

ipc: use kmalloc for msg_queue and shmid_kernel

msg_queue and shmid_kernel are quite small objects, no need to use
kvmalloc for them. mhocko@: "Both of them are 256B on most 64b systems."

Previous

ipc: use kmalloc for msg_queue and shmid_kernel

msg_queue and shmid_kernel are quite small objects, no need to use
kvmalloc for them. mhocko@: "Both of them are 256B on most 64b systems."

Previously these objects was allocated via ipc_alloc/ipc_rcu_alloc(),
common function for several ipc objects. It had kvmalloc call inside().
Later, this function went away and was finally replaced by direct kvmalloc
call, and now we can use more suitable kmalloc/kfree for them.

Link: https://lkml.kernel.org/r/0d0b6c9b-8af3-29d8-34e2-a565c53780f3@virtuozzo.com
Reported-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Vasily Averin <vvs@virtuozzo.com>
Acked-by: Michal Hocko <mhocko@suse.com>
Reviewed-by: Shakeel Butt <shakeelb@google.com>
Acked-by: Roman Gushchin <guro@fb.com>
Cc: Johannes Weiner <hannes@cmpxchg.org>
Cc: Vladimir Davydov <vdavydov.dev@gmail.com>
Cc: Dmitry Safonov <0x7f454c46@gmail.com>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Cc: Manfred Spraul <manfred@colorfullife.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

show more ...

Reimplement RLIMIT_MEMLOCK on top of ucounts

The rlimit counter is tied to uid in the user_namespace. This allows
rlimit values to be specified in userns even if they are already
globally exceeded b

Reimplement RLIMIT_MEMLOCK on top of ucounts

The rlimit counter is tied to uid in the user_namespace. This allows
rlimit values to be specified in userns even if they are already
globally exceeded by the user. However, the value of the previous
user_namespaces cannot be exceeded.

Changelog

v11:
* Fix issue found by lkp robot.

v8:
* Fix issues found by lkp-tests project.

v7:
* Keep only ucounts for RLIMIT_MEMLOCK checks instead of struct cred.

v6:
* Fix bug in hugetlb_file_setup() detected by trinity.

Reported-by: kernel test robot <oliver.sang@intel.com>
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Alexey Gladkov <legion@kernel.org>
Link: https://lkml.kernel.org/r/970d50c70c71bfd4496e0e8d2a0a32feebebb350.1619094428.git.legion@kernel.org
Signed-off-by: Eric W. Biederman <ebiederm@xmission.com>

show more ...

vm_ops: rename .split() callback to .may_split()

Rename the callback to reflect that it's not called *on* or *after* split,
but rather some time before the splitting to check if it's possible.

Link

vm_ops: rename .split() callback to .may_split()

Rename the callback to reflect that it's not called *on* or *after* split,
but rather some time before the splitting to check if it's possible.

Link: https://lkml.kernel.org/r/20201013013416.390574-5-dima@arista.com
Signed-off-by: Dmitry Safonov <dima@arista.com>
Cc: Alexander Viro <viro@zeniv.linux.org.uk>
Cc: Andy Lutomirski <luto@kernel.org>
Cc: Brian Geffon <bgeffon@google.com>
Cc: Catalin Marinas <catalin.marinas@arm.com>
Cc: Dan Carpenter <dan.carpenter@oracle.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: Dave Jiang <dave.jiang@intel.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jason Gunthorpe <jgg@ziepe.ca>
Cc: John Hubbard <jhubbard@nvidia.com>
Cc: "Kirill A. Shutemov" <kirill.shutemov@linux.intel.com>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Minchan Kim <minchan@kernel.org>
Cc: Ralph Campbell <rcampbell@nvidia.com>
Cc: Russell King <linux@armlinux.org.uk>
Cc: Thomas Bogendoerfer <tsbogend@alpha.franken.de>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Vishal Verma <vishal.l.verma@intel.com>
Cc: Vlastimil Babka <vbabka@suse.cz>
Cc: Will Deacon <will@kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

show more ...

treewide: Use fallthrough pseudo-keyword

Replace the existing /* fall through */ comments and its variants with
the new pseudo-keyword macro fallthrough[1]. Also, remove unnecessary
fall-through mar

treewide: Use fallthrough pseudo-keyword

Replace the existing /* fall through */ comments and its variants with
the new pseudo-keyword macro fallthrough[1]. Also, remove unnecessary
fall-through markings when it is the case.

[1] https://www.kernel.org/doc/html/v5.7/process/deprecated.html?highlight=fallthrough#implicit-switch-case-fall-through

Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>

show more ...

ipc/shm.c: remove the superfluous break

Remove the superfuous break, as there is a 'return' before it.

Signed-off-by: Liao Pingfang <liao.pingfang@zte.com.cn>
Signed-off-by: Yi Wang <wang.yi59@zte.

ipc/shm.c: remove the superfluous break

Remove the superfuous break, as there is a 'return' before it.

Signed-off-by: Liao Pingfang <liao.pingfang@zte.com.cn>
Signed-off-by: Yi Wang <wang.yi59@zte.com.cn>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Link: http://lkml.kernel.org/r/1594724361-11525-1-git-send-email-wang.yi59@zte.com.cn
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

show more ...

ipc: uninline functions

Two functions are only called via function pointers, don't bother
inlining them.

Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Andrew Morton <akpm@linu

ipc: uninline functions

Two functions are only called via function pointers, don't bother
inlining them.

Signed-off-by: Alexey Dobriyan <adobriyan@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Manfred Spraul <manfred@colorfullife.com>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Link: http://lkml.kernel.org/r/20200710200312.GA960353@localhost.localdomain
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

show more ...

mm: remove unnecessary wrapper function do_mmap_pgoff()

The current split between do_mmap() and do_mmap_pgoff() was introduced in
commit 1fcfd8db7f82 ("mm, mpx: add "vm_flags_t vm_flags" arg to
do_m

mm: remove unnecessary wrapper function do_mmap_pgoff()

The current split between do_mmap() and do_mmap_pgoff() was introduced in
commit 1fcfd8db7f82 ("mm, mpx: add "vm_flags_t vm_flags" arg to
do_mmap_pgoff()") to support MPX.

The wrapper function do_mmap_pgoff() always passed 0 as the value of the
vm_flags argument to do_mmap(). However, MPX support has subsequently
been removed from the kernel and there were no more direct callers of
do_mmap(); all calls were going via do_mmap_pgoff().

Simplify the code by removing do_mmap_pgoff() and changing all callers to
directly call do_mmap(), which now no longer takes a vm_flags argument.

Signed-off-by: Peter Collingbourne <pcc@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: David Hildenbrand <david@redhat.com>
Link: http://lkml.kernel.org/r/20200727194109.1371462-1-pcc@google.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

show more ...

mmap locking API: use coccinelle to convert mmap_sem rwsem call sites

This change converts the existing mmap_sem rwsem calls to use the new mmap
locking API instead.

The change is generated using c

mmap locking API: use coccinelle to convert mmap_sem rwsem call sites

This change converts the existing mmap_sem rwsem calls to use the new mmap
locking API instead.

The change is generated using coccinelle with the following rule:

// spatch --sp-file mmap_lock_api.cocci --in-place --include-headers --dir .

@@
expression mm;
@@
(
-init_rwsem
+mmap_init_lock
|
-down_write
+mmap_write_lock
|
-down_write_killable
+mmap_write_lock_killable
|
-down_write_trylock
+mmap_write_trylock
|
-up_write
+mmap_write_unlock
|
-downgrade_write
+mmap_write_downgrade
|
-down_read
+mmap_read_lock
|
-down_read_killable
+mmap_read_lock_killable
|
-down_read_trylock
+mmap_read_trylock
|
-up_read
+mmap_read_unlock
)
-(&mm->mmap_sem)
+(mm)

Signed-off-by: Michel Lespinasse <walken@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Reviewed-by: Daniel Jordan <daniel.m.jordan@oracle.com>
Reviewed-by: Laurent Dufour <ldufour@linux.ibm.com>
Reviewed-by: Vlastimil Babka <vbabka@suse.cz>
Cc: Davidlohr Bueso <dbueso@suse.de>
Cc: David Rientjes <rientjes@google.com>
Cc: Hugh Dickins <hughd@google.com>
Cc: Jason Gunthorpe <jgg@ziepe.ca>
Cc: Jerome Glisse <jglisse@redhat.com>
Cc: John Hubbard <jhubbard@nvidia.com>
Cc: Liam Howlett <Liam.Howlett@oracle.com>
Cc: Matthew Wilcox <willy@infradead.org>
Cc: Peter Zijlstra <peterz@infradead.org>
Cc: Ying Han <yinghan@google.com>
Link: http://lkml.kernel.org/r/20200520052908.204642-5-walken@google.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

show more ...

ipc/shm.c: make compat_ksys_shmctl() static

Fix the following sparse warning:

ipc/shm.c:1335:6: warning: symbol 'compat_ksys_shmctl' was not declared.
Should it be static?

Reported-by: Hulk Robot

ipc/shm.c: make compat_ksys_shmctl() static

Fix the following sparse warning:

ipc/shm.c:1335:6: warning: symbol 'compat_ksys_shmctl' was not declared.
Should it be static?

Reported-by: Hulk Robot <hulkci@huawei.com>
Signed-off-by: Jason Yan <yanaijie@huawei.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Link: http://lkml.kernel.org/r/20200403063933.24785-1-yanaijie@huawei.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

show more ...

ipc: rename old-style shmctl/semctl/msgctl syscalls

The behavior of these system calls is slightly different between
architectures, as determined by the CONFIG_ARCH_WANT_IPC_PARSE_VERSION
symbol. Mo

ipc: rename old-style shmctl/semctl/msgctl syscalls

The behavior of these system calls is slightly different between
architectures, as determined by the CONFIG_ARCH_WANT_IPC_PARSE_VERSION
symbol. Most architectures that implement the split IPC syscalls don't set
that symbol and only get the modern version, but alpha, arm, microblaze,
mips-n32, mips-n64 and xtensa expect the caller to pass the IPC_64 flag.

For the architectures that so far only implement sys_ipc(), i.e. m68k,
mips-o32, powerpc, s390, sh, sparc, and x86-32, we want the new behavior
when adding the split syscalls, so we need to distinguish between the
two groups of architectures.

The method I picked for this distinction is to have a separate system call
entry point: sys_old_*ctl() now uses ipc_parse_version, while sys_*ctl()
does not. The system call tables of the five architectures are changed
accordingly.

As an additional benefit, we no longer need the configuration specific
definition for ipc_parse_version(), it always does the same thing now,
but simply won't get called on architectures with the modern interface.

A small downside is that on architectures that do set
ARCH_WANT_IPC_PARSE_VERSION, we now have an extra set of entry points
that are never called. They only add a few bytes of bloat, so it seems
better to keep them compared to adding yet another Kconfig symbol.
I considered adding new syscall numbers for the IPC_64 variants for
consistency, but decided against that for now.

Signed-off-by: Arnd Bergmann <arnd@arndb.de>

show more ...

ipc/shm.c: use ERR_CAST() for shm_lock() error return

This uses ERR_CAST() instead of an open-coded cast, as it is casting
across structure pointers, which upsets __randomize_layout:

ipc/shm.c: In

ipc/shm.c: use ERR_CAST() for shm_lock() error return

This uses ERR_CAST() instead of an open-coded cast, as it is casting
across structure pointers, which upsets __randomize_layout:

ipc/shm.c: In function `shm_lock':
ipc/shm.c:209:9: note: randstruct: casting between randomized structure pointer types (ssa): `struct shmid_kernel' and `struct kern_ipc_perm'

return (void *)ipcp;
^~~~~~~~~~~~

Link: http://lkml.kernel.org/r/20180919180722.GA15073@beast
Fixes: 82061c57ce93 ("ipc: drop ipc_lock()")
Signed-off-by: Kees Cook <keescook@chromium.org>
Cc: Davidlohr Bueso <dbueso@suse.de>
Cc: Manfred Spraul <manfred@colorfullife.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

show more ...

ipc/shm: properly return EIDRM in shm_lock()

When getting rid of the general ipc_lock(), this was missed furthermore,
making the comment around the ipc object validity check bogus. Under
EIDRM cond

ipc/shm: properly return EIDRM in shm_lock()

When getting rid of the general ipc_lock(), this was missed furthermore,
making the comment around the ipc object validity check bogus. Under
EIDRM conditions, callers will in turn not see the error and continue
with the operation.

Link: http://lkml.kernel.org/r/20180824030920.GD3677@linux-r8p5
Link: http://lkml.kernel.org/r/20180823024051.GC13343@shao2-debian
Fixes: 82061c57ce9 ("ipc: drop ipc_lock()")
Signed-off-by: Davidlohr Bueso <dbueso@suse.de>
Reported-by: kernel test robot <rong.a.chen@intel.com>
Cc: Manfred Spraul <manfred@colorfullife.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

show more ...

y2038: globally rename compat_time to old_time32

Christoph Hellwig suggested a slightly different path for handling
backwards compatibility with the 32-bit time_t based system calls:

Rather than si

y2038: globally rename compat_time to old_time32

Christoph Hellwig suggested a slightly different path for handling
backwards compatibility with the 32-bit time_t based system calls:

Rather than simply reusing the compat_sys_* entry points on 32-bit
architectures unchanged, we get rid of those entry points and the
compat_time types by renaming them to something that makes more sense
on 32-bit architectures (which don't have a compat mode otherwise),
and then share the entry points under the new name with the 64-bit
architectures that use them for implementing the compatibility.

The following types and interfaces are renamed here, and moved
from linux/compat_time.h to linux/time32.h:

old new
--- ---
compat_time_t old_time32_t
struct compat_timeval struct old_timeval32
struct compat_timespec struct old_timespec32
struct compat_itimerspec struct old_itimerspec32
ns_to_compat_timeval() ns_to_old_timeval32()
get_compat_itimerspec64() get_old_itimerspec32()
put_compat_itimerspec64() put_old_itimerspec32()
compat_get_timespec64() get_old_timespec32()
compat_put_timespec64() put_old_timespec32()

As we already have aliases in place, this patch addresses only the
instances that are relevant to the system call interface in particular,
not those that occur in device drivers and other modules. Those
will get handled separately, while providing the 64-bit version
of the respective interfaces.

I'm not renaming the timex, rusage and itimerval structures, as we are
still debating what the new interface will look like, and whether we
will need a replacement at all.

This also doesn't change the names of the syscall entry points, which can
be done more easily when we actually switch over the 32-bit architectures
to use them, at that point we need to change COMPAT_SYSCALL_DEFINEx to
SYSCALL_DEFINEx with a new name, e.g. with a _time32 suffix.

Suggested-by: Christoph Hellwig <hch@infradead.org>
Link: https://lore.kernel.org/lkml/20180705222110.GA5698@infradead.org/
Signed-off-by: Arnd Bergmann <arnd@arndb.de>

show more ...

ipc/util.c: further variable name cleanups

The varable names got a mess, thus standardize them again:

id: user space id. Called semid, shmid, msgid if the type is known.
Most functions use "id"

ipc/util.c: further variable name cleanups

The varable names got a mess, thus standardize them again:

id: user space id. Called semid, shmid, msgid if the type is known.
Most functions use "id" already.
idx: "index" for the idr lookup
Right now, some functions use lid, ipc_addid() already uses idx as
the variable name.
seq: sequence number, to avoid quick collisions of the user space id
key: user space key, used for the rhash tree

Link: http://lkml.kernel.org/r/20180712185241.4017-12-manfred@colorfullife.com
Signed-off-by: Manfred Spraul <manfred@colorfullife.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Davidlohr Bueso <dave@stgolabs.net>
Cc: Davidlohr Bueso <dbueso@suse.de>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: Kees Cook <keescook@chromium.org>
Cc: Michael Kerrisk <mtk.manpages@gmail.com>
Cc: Michal Hocko <mhocko@suse.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

show more ...

ipc: simplify ipc initialization

Now that we know that rhashtable_init() will not fail, we can get rid of a
lot of the unnecessary cleanup paths when the call errored out.

[manfred@colorfullife.com

ipc: simplify ipc initialization

Now that we know that rhashtable_init() will not fail, we can get rid of a
lot of the unnecessary cleanup paths when the call errored out.

[manfred@colorfullife.com: variable name added to util.h to resolve checkpatch warning]
Link: http://lkml.kernel.org/r/20180712185241.4017-11-manfred@colorfullife.com
Signed-off-by: Davidlohr Bueso <dbueso@suse.de>
Signed-off-by: Manfred Spraul <manfred@colorfullife.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: Kees Cook <keescook@chromium.org>
Cc: Michael Kerrisk <mtk.manpages@gmail.com>
Cc: Michal Hocko <mhocko@suse.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

show more ...

ipc: drop ipc_lock()

ipc/util.c contains multiple functions to get the ipc object pointer given
an id number.

There are two sets of function: One set verifies the sequence counter part
of the id nu

ipc: drop ipc_lock()

ipc/util.c contains multiple functions to get the ipc object pointer given
an id number.

There are two sets of function: One set verifies the sequence counter part
of the id number, other functions do not check the sequence counter.

The standard for function names in ipc/util.c is
- ..._check() functions verify the sequence counter
- ..._idr() functions do not verify the sequence counter

ipc_lock() is an exception: It does not verify the sequence counter value,
but this is not obvious from the function name.

Furthermore, shm.c is the only user of this helper. Thus, we can simply
move the logic into shm_lock() and get rid of the function altogether.

[manfred@colorfullife.com: most of changelog]
Link: http://lkml.kernel.org/r/20180712185241.4017-7-manfred@colorfullife.com
Signed-off-by: Davidlohr Bueso <dbueso@suse.de>
Signed-off-by: Manfred Spraul <manfred@colorfullife.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Herbert Xu <herbert@gondor.apana.org.au>
Cc: Kees Cook <keescook@chromium.org>
Cc: Michael Kerrisk <mtk.manpages@gmail.com>
Cc: Michal Hocko <mhocko@suse.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

show more ...