diff options
| author | Xiubo Li <xiubli@redhat.com> | 2020-07-06 14:51:35 +0200 |
|---|---|---|
| committer | Ilya Dryomov <idryomov@gmail.com> | 2020-08-03 11:05:25 +0200 |
| commit | d1d9655052606fd9078e896668ec90191372d513 (patch) | |
| tree | dcdb21734df1009fd848b91d7d3d54fbd57387b0 | |
| parent | ceph: clean up and optimize ceph_check_delayed_caps() (diff) | |
| download | linux-d1d9655052606fd9078e896668ec90191372d513.tar.xz linux-d1d9655052606fd9078e896668ec90191372d513.zip | |
ceph: do not access the kiocb after aio requests
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>
| -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); |