On 3/2/20 11:13 AM, gregkh@linuxfoundation.org wrote:
The patch below does not apply to the 5.4-stable tree. If someone wants it applied there, or to any other stable or longterm tree, then please email the backport, including the original git commit id to stable@vger.kernel.org.
Here's a 5.4 version.
commit d876836204897b6d7d911f942084f69a1e9d5c4d Author: Jens Axboe axboe@kernel.dk Date: Thu Feb 27 14:17:49 2020 -0700
io_uring: fix 32-bit compatability with sendmsg/recvmsg
We must set MSG_CMSG_COMPAT if we're in compatability mode, otherwise the iovec import for these commands will not do the right thing and fail the command with -EINVAL.
Found by running the test suite compiled as 32-bit.
Cc: stable@vger.kernel.org Fixes: aa1fa28fc73e ("io_uring: add support for recvmsg()") Fixes: 0fa03c624d8f ("io_uring: add support for sendmsg()") Signed-off-by: Jens Axboe axboe@kernel.dk
diff --git a/fs/io_uring.c b/fs/io_uring.c index 607edaef5e71..4e7504eeb015 100644 --- a/fs/io_uring.c +++ b/fs/io_uring.c @@ -1666,6 +1666,11 @@ static int io_send_recvmsg(struct io_kiocb *req, const struct io_uring_sqe *sqe, else if (force_nonblock) flags |= MSG_DONTWAIT;
+#ifdef CONFIG_COMPAT + if (req->ctx->compat) + flags |= MSG_CMSG_COMPAT; +#endif + msg = (struct user_msghdr __user *) (unsigned long) READ_ONCE(sqe->addr);