diff options
| author | Jens Axboe <axboe@kernel.dk> | 2020-11-20 07:59:54 -0700 |
|---|---|---|
| committer | Jakub Kicinski <kuba@kernel.org> | 2020-11-21 15:19:08 -0800 |
| commit | 5aac0390a63b8718237a61dd0d24a29201d1c94a (patch) | |
| tree | 9b8e18b051dca28b2a2c5796f83f5990faa3018f /drivers/net | |
| parent | c5dab0941fcdc9664eb0ec0d4d51433216d91336 (diff) | |
| download | linux-5aac0390a63b8718237a61dd0d24a29201d1c94a.tar.gz | |
tun: honor IOCB_NOWAIT flag
tun only checks the file O_NONBLOCK flag, but it should also be checking
the iocb IOCB_NOWAIT flag. Any fops using ->read/write_iter() should check
both, otherwise it breaks users that correctly expect O_NONBLOCK semantics
if IOCB_NOWAIT is set.
Signed-off-by: Jens Axboe <axboe@kernel.dk>
Link: https://lore.kernel.org/r/e9451860-96cc-c7c7-47b8-fe42cadd5f4c@kernel.dk
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Diffstat (limited to 'drivers/net')
| -rw-r--r-- | drivers/net/tun.c | 14 |
1 files changed, 11 insertions, 3 deletions
diff --git a/drivers/net/tun.c b/drivers/net/tun.c index be69d272052f..cd06cae76035 100644 --- a/drivers/net/tun.c +++ b/drivers/net/tun.c @@ -1961,12 +1961,15 @@ static ssize_t tun_chr_write_iter(struct kiocb *iocb, struct iov_iter *from) struct tun_file *tfile = file->private_data; struct tun_struct *tun = tun_get(tfile); ssize_t result; + int noblock = 0; if (!tun) return -EBADFD; - result = tun_get_user(tun, tfile, NULL, from, - file->f_flags & O_NONBLOCK, false); + if ((file->f_flags & O_NONBLOCK) || (iocb->ki_flags & IOCB_NOWAIT)) + noblock = 1; + + result = tun_get_user(tun, tfile, NULL, from, noblock, false); tun_put(tun); return result; @@ -2185,10 +2188,15 @@ static ssize_t tun_chr_read_iter(struct kiocb *iocb, struct iov_iter *to) struct tun_file *tfile = file->private_data; struct tun_struct *tun = tun_get(tfile); ssize_t len = iov_iter_count(to), ret; + int noblock = 0; if (!tun) return -EBADFD; - ret = tun_do_read(tun, tfile, to, file->f_flags & O_NONBLOCK, NULL); + + if ((file->f_flags & O_NONBLOCK) || (iocb->ki_flags & IOCB_NOWAIT)) + noblock = 1; + + ret = tun_do_read(tun, tfile, to, noblock, NULL); ret = min_t(ssize_t, ret, len); if (ret > 0) iocb->ki_pos = ret; |