3.10-stable review patch. If anyone has any objections, please let me know.
------------------ From: Greg Kroah-Hartman <[email protected]> In Linus's tree, the iovec code has been reworked massively, but in older kernels the AIO layer should be checking this before passing the request on to other layers. Many thanks to Ben Hawkes of Google Project Zero for pointing out the issue. Reported-by: Ben Hawkes <[email protected]> Acked-by: Benjamin LaHaise <[email protected]> Tested-by: Willy Tarreau <[email protected]> [backported to 3.10 - willy] Signed-off-by: Greg Kroah-Hartman <[email protected]> --- fs/aio.c | 11 ++++++++--- 1 file changed, 8 insertions(+), 3 deletions(-) --- a/fs/aio.c +++ b/fs/aio.c @@ -977,12 +977,17 @@ static ssize_t aio_setup_vectored_rw(int static ssize_t aio_setup_single_vector(int rw, struct kiocb *kiocb) { - if (unlikely(!access_ok(!rw, kiocb->ki_buf, kiocb->ki_nbytes))) - return -EFAULT; + size_t len = kiocb->ki_nbytes; + + if (len > MAX_RW_COUNT) + len = MAX_RW_COUNT; + + if (unlikely(!access_ok(!rw, kiocb->ki_buf, len))) + return -EFAULT; kiocb->ki_iovec = &kiocb->ki_inline_vec; kiocb->ki_iovec->iov_base = kiocb->ki_buf; - kiocb->ki_iovec->iov_len = kiocb->ki_nbytes; + kiocb->ki_iovec->iov_len = len; kiocb->ki_nr_segs = 1; return 0; }
