From: Pavel Begunkov <asml.silence@xxxxxxxxx> commit 3a1b8a4e843f96b636431450d8d79061605cf74b upstream. Limit the number of files in io_uring fixed tables by RLIMIT_NOFILE, that's the first and the simpliest restriction that we should impose. Cc: stable@xxxxxxxxxxxxxxx Suggested-by: Jens Axboe <axboe@xxxxxxxxx> Signed-off-by: Pavel Begunkov <asml.silence@xxxxxxxxx> Link: https://lore.kernel.org/r/b2756c340aed7d6c0b302c26dab50c6c5907f4ce.1629451684.git.asml.silence@xxxxxxxxx Signed-off-by: Jens Axboe <axboe@xxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- fs/io_uring.c | 2 ++ 1 file changed, 2 insertions(+) --- a/fs/io_uring.c +++ b/fs/io_uring.c @@ -7669,6 +7669,8 @@ static int io_sqe_files_register(struct return -EINVAL; if (nr_args > IORING_MAX_FIXED_FILES) return -EMFILE; + if (nr_args > rlimit(RLIMIT_NOFILE)) + return -EMFILE; ret = io_rsrc_node_switch_start(ctx); if (ret) return ret;