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| author | Jens Axboe <axboe@kernel.dk> | 2020-11-20 17:59:54 +0300 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2020-12-08 12:17:33 +0300 |
| commit | d1bea88509fb84852593cacbd5f3c59501936c3c (patch) | |
| tree | 285537dd2b0e3ef51f61bac358c75b039e3d644e /drivers/net/tun.c | |
| parent | 2d375e703f00a2ac60f6530b8dc924bdcfac4ef4 (diff) | |
| download | linux-d1bea88509fb84852593cacbd5f3c59501936c3c.tar.xz | |
tun: honor IOCB_NOWAIT flag
[ Upstream commit 5aac0390a63b8718237a61dd0d24a29201d1c94a ]
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>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/net/tun.c')
| -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 ba34f61d70de..abf9c9952b79 100644 --- a/drivers/net/tun.c +++ b/drivers/net/tun.c @@ -1601,12 +1601,15 @@ static ssize_t tun_chr_write_iter(struct kiocb *iocb, struct iov_iter *from) struct tun_struct *tun = tun_get(file); struct tun_file *tfile = file->private_data; 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; @@ -1789,10 +1792,15 @@ 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; |