From: Jens Axboe <axboe@kernel.dk>
Date: Fri, 3 Apr 2020 19:54:26 +0000 (-0600)
Subject: io_uring: remove bogus RLIMIT_NOFILE check in file registration
X-Git-Tag: v5.7-rc1~28^2~12
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=c336e992cb1cb1db9ee608dfb30342ae781057ab;p=thirdparty%2Flinux.git

io_uring: remove bogus RLIMIT_NOFILE check in file registration

We already checked this limit when the file was opened, and we keep it
open in the file table. Hence when we added unit_inflight to the count
we want to register, we're doubly accounting these files. This results
in -EMFILE for file registration, if we're at half the limit.

Cc: stable@vger.kernel.org # v5.1+
Signed-off-by: Jens Axboe <axboe@kernel.dk>
---

diff --git a/fs/io_uring.c b/fs/io_uring.c
index 2460c3333f700..ce76157c2f959 100644
--- a/fs/io_uring.c
+++ b/fs/io_uring.c
@@ -6216,13 +6216,6 @@ static int __io_sqe_files_scm(struct io_ring_ctx *ctx, int nr, int offset)
 	struct sk_buff *skb;
 	int i, nr_files;
 
-	if (!capable(CAP_SYS_RESOURCE) && !capable(CAP_SYS_ADMIN)) {
-		unsigned long inflight = ctx->user->unix_inflight + nr;
-
-		if (inflight > task_rlimit(current, RLIMIT_NOFILE))
-			return -EMFILE;
-	}
-
 	fpl = kzalloc(sizeof(*fpl), GFP_KERNEL);
 	if (!fpl)
 		return -ENOMEM;