From: Jens Axboe Date: Sat, 19 Sep 2020 01:36:24 +0000 (-0600) Subject: io_uring: fix openat/openat2 unified prep handling X-Git-Tag: v5.8.13~42 X-Git-Url: http://git.ipfire.org/gitweb.cgi?a=commitdiff_plain;h=96c45a01f4432724ffd6b95688fc5867f6025215;p=thirdparty%2Fkernel%2Fstable.git io_uring: fix openat/openat2 unified prep handling [ Upstream commit 4eb8dded6b82e184c09bb963bea0335fa3f30b55 ] A previous commit unified how we handle prep for these two functions, but this means that we check the allowed context (SQPOLL, specifically) later than we should. Move the ring type checking into the two parent functions, instead of doing it after we've done some setup work. Fixes: ec65fea5a8d7 ("io_uring: deduplicate io_openat{,2}_prep()") Reported-by: Andy Lutomirski Signed-off-by: Jens Axboe Signed-off-by: Sasha Levin --- diff --git a/fs/io_uring.c b/fs/io_uring.c index d05023ca74bdc..849e39c3cfcd7 100644 --- a/fs/io_uring.c +++ b/fs/io_uring.c @@ -3056,8 +3056,6 @@ static int __io_openat_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe const char __user *fname; int ret; - if (unlikely(req->ctx->flags & (IORING_SETUP_IOPOLL|IORING_SETUP_SQPOLL))) - return -EINVAL; if (unlikely(sqe->ioprio || sqe->buf_index)) return -EINVAL; if (unlikely(req->flags & REQ_F_FIXED_FILE)) @@ -3084,6 +3082,8 @@ static int io_openat_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe) { u64 flags, mode; + if (unlikely(req->ctx->flags & (IORING_SETUP_IOPOLL|IORING_SETUP_SQPOLL))) + return -EINVAL; if (req->flags & REQ_F_NEED_CLEANUP) return 0; mode = READ_ONCE(sqe->len); @@ -3098,6 +3098,8 @@ static int io_openat2_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe) size_t len; int ret; + if (unlikely(req->ctx->flags & (IORING_SETUP_IOPOLL|IORING_SETUP_SQPOLL))) + return -EINVAL; if (req->flags & REQ_F_NEED_CLEANUP) return 0; how = u64_to_user_ptr(READ_ONCE(sqe->addr2));