From d7cce96c449e35bbfd41e830b341b95973891eed Mon Sep 17 00:00:00 2001 From: Pavel Begunkov Date: Tue, 27 Sep 2022 01:13:30 +0100 Subject: [PATCH] io_uring: limit registration w/ SINGLE_ISSUER IORING_SETUP_SINGLE_ISSUER restricts what tasks can submit requests. Extend it to registration as well, so non-owning task can't do registrations. It's not necessary at the moment but might be useful in the future. Cc: # 6.0 Fixes: 97bbdc06a444 ("io_uring: add IORING_SETUP_SINGLE_ISSUER") Signed-off-by: Pavel Begunkov Link: https://lore.kernel.org/r/f52a6a9c8a8990d4a831f73c0571e7406aac2bba.1664237592.git.asml.silence@gmail.com Signed-off-by: Jens Axboe --- io_uring/io_uring.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/io_uring/io_uring.c b/io_uring/io_uring.c index fe6ef64c873e..63f6ce5e5355 100644 --- a/io_uring/io_uring.c +++ b/io_uring/io_uring.c @@ -3890,6 +3890,9 @@ static int __io_uring_register(struct io_ring_ctx *ctx, unsigned opcode, if (WARN_ON_ONCE(percpu_ref_is_dying(&ctx->refs))) return -ENXIO; + if (ctx->submitter_task && ctx->submitter_task != current) + return -EEXIST; + if (ctx->restricted) { if (opcode >= IORING_REGISTER_LAST) return -EINVAL;