linux-toradex.git/mm/process_vm_access.c, branch v5.12-rc5

mm/process_vm_access.c: include compat.h

2021-01-13T02:12:54+00:00

Fix the build error:

  mm/process_vm_access.c:277:5: error: implicit declaration of function 'in_compat_syscall'; did you mean 'in_ia32_syscall'? [-Werror=implicit-function-declaration]

Fixes: 38dc5079da7081e "Fix compat regression in process_vm_rw()"
Reported-by: syzbot+5b0d0de84d6c65b8dd2b@syzkaller.appspotmail.com
Cc: Kyle Huey 
Cc: Jens Axboe 
Cc: Al Viro 
Cc: Christoph Hellwig 
Cc: 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

mm/process_vm_access: remove redundant initialization of iov_r

2020-12-15T20:13:46+00:00

The pointer iov_r is being initialized with a value that is never read and
it is being updated later with a new value.  The initialization is
redundant and can be removed.

Link: https://lkml.kernel.org/r/20201102120614.694917-1-colin.king@canonical.com
Signed-off-by: Colin Ian King 
Reviewed-by: Andrew Morton 
Signed-off-by: Andrew Morton 
Signed-off-by: Linus Torvalds

mm/process_vm_access: Add missing #include

2020-10-27T19:41:29+00:00

With e.g. m68k/defconfig:

    mm/process_vm_access.c: In function ‘process_vm_rw’:
    mm/process_vm_access.c:277:5: error: implicit declaration of function ‘in_compat_syscall’ [-Werror=implicit-function-declaration]
      277 |     in_compat_syscall());
	  |     ^~~~~~~~~~~~~~~~~

Fix this by adding #include .

Reported-by: noreply@ellerman.id.au
Reported-by: damian 
Reported-by: Naresh Kamboju 
Fixes: 38dc5079da7081e8 ("Fix compat regression in process_vm_rw()")
Signed-off-by: Geert Uytterhoeven 
Acked-by: Jens Axboe 
Signed-off-by: Linus Torvalds

Fix compat regression in process_vm_rw()

2020-10-27T16:57:46+00:00

The removal of compat_process_vm_{readv,writev} didn't change
process_vm_rw(), which always assumes it's not doing a compat syscall.

Instead of passing in 'false' unconditionally for 'compat', make it
conditional on in_compat_syscall().

[ Both Al and Christoph point out that trying to access a 64-bit process
  from a 32-bit one cannot work anyway, and is likely better prohibited,
  but that's a separate issue    - Linus ]

Fixes: c3973b401ef2 ("mm: remove compat_process_vm_{readv,writev}")
Reported-and-tested-by: Kyle Huey 
Signed-off-by: Jens Axboe 
Acked-by: Al Viro 
Reviewed-by: Christoph Hellwig 
Signed-off-by: Linus Torvalds

mm: remove compat_process_vm_{readv,writev}

2020-10-03T04:02:15+00:00

Now that import_iovec handles compat iovecs, the native syscalls
can be used for the compat case as well.

Signed-off-by: Christoph Hellwig 
Signed-off-by: Al Viro

iov_iter: transparently handle compat iovecs in import_iovec

2020-10-03T04:02:13+00:00

Use in compat_syscall to import either native or the compat iovecs, and
remove the now superflous compat_import_iovec.

This removes the need for special compat logic in most callers, and
the remaining ones can still be simplified by using __import_iovec
with a bool compat parameter.

Signed-off-by: Christoph Hellwig 
Signed-off-by: Al Viro

iov_iter: refactor rw_copy_check_uvector and import_iovec

2020-10-03T04:01:56+00:00

Split rw_copy_check_uvector into two new helpers with more sensible
calling conventions:

 - iovec_from_user copies a iovec from userspace either into the provided
   stack buffer if it fits, or allocates a new buffer for it.  Returns
   the actually used iovec.  It also verifies that iov_len does fit a
   signed type, and handles compat iovecs if the compat flag is set.
 - __import_iovec consolidates the native and compat versions of
   import_iovec. It calls iovec_from_user, then validates each iovec
   actually points to user addresses, and ensures the total length
   doesn't overflow.

This has two major implications:

 - the access_process_vm case loses the total lenght checking, which
   wasn't required anyway, given that each call receives two iovecs
   for the local and remote side of the operation, and it verifies
   the total length on the local side already.
 - instead of a single loop there now are two loops over the iovecs.
   Given that the iovecs are cache hot this doesn't make a major
   difference

Signed-off-by: Christoph Hellwig 
Signed-off-by: Al Viro

mm/gup: remove task_struct pointer for all gup code

2020-08-12T17:58:04+00:00

After the cleanup of page fault accounting, gup does not need to pass
task_struct around any more.  Remove that parameter in the whole gup
stack.

Signed-off-by: Peter Xu 
Signed-off-by: Andrew Morton 
Reviewed-by: John Hubbard 
Link: http://lkml.kernel.org/r/20200707225021.200906-26-peterx@redhat.com
Signed-off-by: Linus Torvalds

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

2020-06-09T16:39:14+00:00

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 
Signed-off-by: Andrew Morton 
Reviewed-by: Daniel Jordan 
Reviewed-by: Laurent Dufour 
Reviewed-by: Vlastimil Babka 
Cc: Davidlohr Bueso 
Cc: David Rientjes 
Cc: Hugh Dickins 
Cc: Jason Gunthorpe 
Cc: Jerome Glisse 
Cc: John Hubbard 
Cc: Liam Howlett 
Cc: Matthew Wilcox 
Cc: Peter Zijlstra 
Cc: Ying Han 
Link: http://lkml.kernel.org/r/20200520052908.204642-5-walken@google.com
Signed-off-by: Linus Torvalds

mm: docs: Fix a comment in process_vm_rw_core

2020-03-25T15:04:01+00:00

This removes a duplicate "a" in the comment in process_vm_rw_core.

Signed-off-by: Bernd Edlinger 
Reviewed-by: Kees Cook 
Signed-off-by: Eric W. Biederman