diff options
| author | Mike Rapoport <rppt@linux.vnet.ibm.com> | 2017-03-10 01:17:09 +0100 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2017-03-10 02:01:10 +0100 |
| commit | 7eb76d457fd758d396bc2e65cb0ace5aae614149 (patch) | |
| tree | 65cef25c2ccabe3574891256e13292939270bdce /fs/userfaultfd.c | |
| parent | mm/cgroup: avoid panic when init with low memory (diff) | |
| download | linux-7eb76d457fd758d396bc2e65cb0ace5aae614149.tar.xz linux-7eb76d457fd758d396bc2e65cb0ace5aae614149.zip | |
userfaultfd: non-cooperative: fix fork fctx->new memleak
We have a memleak in the ->new ctx if the uffd of the parent is closed
before the fork event is read, nothing frees the new context.
Link: http://lkml.kernel.org/r/20170302173738.18994-2-aarcange@redhat.com
Signed-off-by: Mike Rapoport <rppt@linux.vnet.ibm.com>
Signed-off-by: Andrea Arcangeli <aarcange@redhat.com>
Reported-by: Andrea Arcangeli <aarcange@redhat.com>
Cc: "Dr. David Alan Gilbert" <dgilbert@redhat.com>
Cc: Mike Kravetz <mike.kravetz@oracle.com>
Cc: Pavel Emelyanov <xemul@parallels.com>
Cc: Hillf Danton <hillf.zj@alibaba-inc.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'fs/userfaultfd.c')
| -rw-r--r-- | fs/userfaultfd.c | 9 |
1 files changed, 9 insertions, 0 deletions
diff --git a/fs/userfaultfd.c b/fs/userfaultfd.c index dd48052e086f..2407249998c3 100644 --- a/fs/userfaultfd.c +++ b/fs/userfaultfd.c @@ -549,6 +549,15 @@ static void userfaultfd_event_wait_completion(struct userfaultfd_ctx *ctx, if (ACCESS_ONCE(ctx->released) || fatal_signal_pending(current)) { __remove_wait_queue(&ctx->event_wqh, &ewq->wq); + if (ewq->msg.event == UFFD_EVENT_FORK) { + struct userfaultfd_ctx *new; + + new = (struct userfaultfd_ctx *) + (unsigned long) + ewq->msg.arg.reserved.reserved1; + + userfaultfd_ctx_put(new); + } break; } |