io_uring: mem-account pbuf buckets

commit cc18cc5e82033d406f54144ad6f8092206004684 upstream.

Potentially, someone may create as many pbuf bucket as there are indexes
in an xarray without any other restrictions bounding our memory usage,
put memory needed for the buckets under memory accounting.

Cc: <stable@vger.kernel.org>
Signed-off-by: Pavel Begunkov <asml.silence@gmail.com>
Link: https://lore.kernel.org/r/d34c452e45793e978d26e2606211ec9070d329ea.1659622312.git.asml.silence@gmail.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/io_uring/io_uring.c b/io_uring/io_uring.c
index 2dd6731c10221e2d7bbfb2916d1cc3d42d9bd4e5..ec4e31c67e07e5e2dd606ce6062b545afb574aac 100644 (file)
--- a/io_uring/io_uring.c
+++ b/io_uring/io_uring.c
@@ -4927,7 +4927,7 @@ static int io_provide_buffers(struct io_kiocb *req, unsigned int issue_flags)
 
        bl = io_buffer_get_list(ctx, p->bgid);
        if (unlikely(!bl)) {
-               bl = kmalloc(sizeof(*bl), GFP_KERNEL);
+               bl = kzalloc(sizeof(*bl), GFP_KERNEL_ACCOUNT);
                if (!bl) {
                        ret = -ENOMEM;
                        goto err;