Skip to content

L
linux
Switch branch/tag
  1. 14 Mar, 2012 2 commits
  3. 10 Mar, 2012 4 commits
    • Linus Torvalds's avatar
      Linux 3.3-rc7 · fde7d904
      Linus Torvalds authored
      fde7d904
    • Al Viro's avatar
      aio: fix the "too late munmap()" race · c7b28555
      Al Viro authored 
      Current code has put_ioctx() called asynchronously from aio_fput_routine();
that's done *after* we have killed the request that used to pin ioctx,
so there's nothing to stop io_destroy() waiting in wait_for_all_aios()
from progressing.  As the result, we can end up with async call of
put_ioctx() being the last one and possibly happening during exit_mmap()
or elf_core_dump(), neither of which expects stray munmap() being done
to them...

We do need to prevent _freeing_ ioctx until aio_fput_routine() is done
with that, but that's all we care about - neither io_destroy() nor
exit_aio() will progress past wait_for_all_aios() until aio_fput_routine()
does really_put_req(), so the ioctx teardown won't be done until then
and we don't care about the contents of ioctx past that point.

Since actual freeing of these suckers is RCU-delayed, we don't need to
bump ioctx refcount when request goes into list for async removal.
All we need is rcu_read_lock held just over the ->ctx_lock-protected
area in aio_fput_routine().
Signed-off-by: default avatarAl Viro <viro@zeniv.linux.org.uk>
Reviewed-by: default avatarJeff Moyer <jmoyer@redhat.com>
Acked-by: default avatarBenjamin LaHaise <bcrl@kvack.org>
Cc: stable@vger.kernel.org
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      c7b28555
    • Al Viro's avatar
      aio: fix io_setup/io_destroy race · 86b62a2c
      Al Viro authored 
      Have ioctx_alloc() return an extra reference, so that caller would drop it
on success and not bother with re-grabbing it on failure exit.  The current
code is obviously broken - io_destroy() from another thread that managed
to guess the address io_setup() would've returned would free ioctx right
under us; gets especially interesting if aio_context_t * we pass to
io_setup() points to PROT_READ mapping, so put_user() fails and we end
up doing io_destroy() on kioctx another thread has just got freed...
Signed-off-by: default avatarAl Viro <viro@zeniv.linux.org.uk>
Acked-by: default avatarBenjamin LaHaise <bcrl@kvack.org>
Reviewed-by: default avatarJeff Moyer <jmoyer@redhat.com>
Cc: stable@vger.kernel.org
Signed-off-by: default avatarLinus Torvalds <torvalds@linux-foundation.org>
      86b62a2c
    • Linus Torvalds's avatar
      Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs · 86e06008
      Linus Torvalds authored 
      Pull btrfs updates from Chris Mason:
 "I have two additional and btrfs fixes in my for-linus branch.  One is
  a casting error that leads to memory corruption on i386 during scrub,
  and the other fixes a corner case in the backref walking code (also
  triggered by scrub)."

* 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/mason/linux-btrfs:
  Btrfs: fix casting error in scrub reada code
  btrfs: fix locking issues in find_parent_nodes()
      86e06008
  5. 09 Mar, 2012 14 commits
  7. 08 Mar, 2012 16 commits
  9. 07 Mar, 2012 4 commits
GitLab Nexedi Edition | About GitLab | About Nexedi | 沪ICP备2021021310号-2 | 沪ICP备2021021310号-7