https://github.com/torvalds/linux
Revision 31e810aa1033a7db50a2746cd34a2432237f6420 authored by Mike Rapoport on 02 August 2018, 22:36:09 UTC, committed by Linus Torvalds on 02 August 2018, 23:03:40 UTC
The fix in commit 0cbb4b4f4c44 ("userfaultfd: clear the
vma->vm_userfaultfd_ctx if UFFD_EVENT_FORK fails") cleared the
vma->vm_userfaultfd_ctx but kept userfaultfd flags in vma->vm_flags
that were copied from the parent process VMA.
As the result, there is an inconsistency between the values of
vma->vm_userfaultfd_ctx.ctx and vma->vm_flags which triggers BUG_ON
in userfaultfd_release().
Clearing the uffd flags from vma->vm_flags in case of UFFD_EVENT_FORK
failure resolves the issue.
Link: http://lkml.kernel.org/r/1532931975-25473-1-git-send-email-rppt@linux.vnet.ibm.com
Fixes: 0cbb4b4f4c44 ("userfaultfd: clear the vma->vm_userfaultfd_ctx if UFFD_EVENT_FORK fails")
Signed-off-by: Mike Rapoport <rppt@linux.vnet.ibm.com>
Reported-by: syzbot+121be635a7a35ddb7dcb@syzkaller.appspotmail.com
Cc: Andrea Arcangeli <aarcange@redhat.com>
Cc: Eric Biggers <ebiggers3@gmail.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
1 parent eec3636
Tip revision: 31e810aa1033a7db50a2746cd34a2432237f6420 authored by Mike Rapoport on 02 August 2018, 22:36:09 UTC
userfaultfd: remove uffd flags from vma->vm_flags if UFFD_EVENT_FORK fails
userfaultfd: remove uffd flags from vma->vm_flags if UFFD_EVENT_FORK fails
Tip revision: 31e810a
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| .clang-format | -rw-r--r-- | 12.8 KB |
| .cocciconfig | -rw-r--r-- | 59 bytes |
| .get_maintainer.ignore | -rw-r--r-- | 31 bytes |
| .gitattributes | -rw-r--r-- | 30 bytes |
| .gitignore | -rw-r--r-- | 1.5 KB |
| .mailmap | -rw-r--r-- | 9.3 KB |
| COPYING | -rw-r--r-- | 423 bytes |
| CREDITS | -rw-r--r-- | 96.3 KB |
| Kbuild | -rw-r--r-- | 2.2 KB |
| Kconfig | -rw-r--r-- | 321 bytes |
| MAINTAINERS | -rw-r--r-- | 449.5 KB |
| Makefile | -rw-r--r-- | 58.2 KB |
| README | -rw-r--r-- | 800 bytes |
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