netdev - [PATCH] tun: flag the device as supporting FMODE

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [thread-next>] [day] [month] [year] [list]

Message-ID: <3f7dc1f0-79ca-d85c-4d16-8c12c5bd492d@kernel.dk>
Date:   Tue, 7 Mar 2023 20:45:56 -0700
From:   Jens Axboe <axboe@...nel.dk>
To:     netdev <netdev@...r.kernel.org>
Cc:     Eric Dumazet <edumazet@...gle.com>,
        Jakub Kicinski <kuba@...nel.org>
Subject: [PATCH] tun: flag the device as supporting FMODE_NOWAIT

tun already checks for both O_NONBLOCK and IOCB_NOWAIT in its read
and write iter handlers, so it's fully ready for FMODE_NOWAIT. But
for some reason it doesn't set it. Rectify that oversight.

Signed-off-by: Jens Axboe <axboe@...nel.dk>

---

diff --git a/drivers/net/tun.c b/drivers/net/tun.c
index ad653b32b2f0..4c7f74904c25 100644
--- a/drivers/net/tun.c
+++ b/drivers/net/tun.c
@@ -3463,6 +3463,8 @@ static int tun_chr_open(struct inode *inode, struct file * file)
 
 	sock_set_flag(&tfile->sk, SOCK_ZEROCOPY);
 
+	/* tun groks IOCB_NOWAIT just fine, mark it as such */
+	file->f_mode |= FMODE_NOWAIT;
 	return 0;
 }
 
-- 
Jens Axboe