diff options
author | Xiubo Li <xiubli@redhat.com> | 2020-07-06 15:51:35 +0300 |
---|---|---|
committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2020-09-03 12:29:22 +0300 |
commit | 3bd5dad493e53ef1574e7c4fcecd787a95fa7aba (patch) | |
tree | 17fdd7bc1953fe6c3578c5eded404a4995a22272 /fs | |
parent | e9c34e71a043ff59a05ac626c475539beb0ee3be (diff) | |
download | linux-3bd5dad493e53ef1574e7c4fcecd787a95fa7aba.tar.xz |
ceph: do not access the kiocb after aio requests
[ Upstream commit d1d9655052606fd9078e896668ec90191372d513 ]
In aio case, if the completion comes very fast just before the
ceph_read_iter() returns to fs/aio.c, the kiocb will be freed in
the completion callback, then if ceph_read_iter() access again
we will potentially hit the use-after-free bug.
[ jlayton: initialize direct_lock early, and use it everywhere ]
URL: https://tracker.ceph.com/issues/45649
Signed-off-by: Xiubo Li <xiubli@redhat.com>
Signed-off-by: Jeff Layton <jlayton@kernel.org>
Signed-off-by: Ilya Dryomov <idryomov@gmail.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Diffstat (limited to 'fs')
-rw-r--r-- | fs/ceph/file.c | 5 |
1 files changed, 3 insertions, 2 deletions
diff --git a/fs/ceph/file.c b/fs/ceph/file.c index 160644ddaeed..d51c3f2fdca0 100644 --- a/fs/ceph/file.c +++ b/fs/ceph/file.c @@ -1538,6 +1538,7 @@ static ssize_t ceph_read_iter(struct kiocb *iocb, struct iov_iter *to) struct inode *inode = file_inode(filp); struct ceph_inode_info *ci = ceph_inode(inode); struct page *pinned_page = NULL; + bool direct_lock = iocb->ki_flags & IOCB_DIRECT; ssize_t ret; int want, got = 0; int retry_op = 0, read = 0; @@ -1546,7 +1547,7 @@ again: dout("aio_read %p %llx.%llx %llu~%u trying to get caps on %p\n", inode, ceph_vinop(inode), iocb->ki_pos, (unsigned)len, inode); - if (iocb->ki_flags & IOCB_DIRECT) + if (direct_lock) ceph_start_io_direct(inode); else ceph_start_io_read(inode); @@ -1603,7 +1604,7 @@ again: } ceph_put_cap_refs(ci, got); - if (iocb->ki_flags & IOCB_DIRECT) + if (direct_lock) ceph_end_io_direct(inode); else ceph_end_io_read(inode); |