tfile->tun could be detached before we close the tun fd, via tun_detach_all(), so it should not be used to check for tfile->tx_array.
As Jason suggested, we probably have to clean it up unconditionally, but this requires to check if it is initialized or not. Currently skb_array_cleanup() doesn't have such a check, so I check it in the caller, it is ugly but we can always improve it in net-next. Reported-by: Dmitry Vyukov <dvyu...@google.com> Fixes: 1576d9860599 ("tun: switch to use skb array for tx") Cc: Jason Wang <jasow...@redhat.com> Signed-off-by: Cong Wang <xiyou.wangc...@gmail.com> --- drivers/net/tun.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/drivers/net/tun.c b/drivers/net/tun.c index 4f4a842a1c9c..4c85474ffbaf 100644 --- a/drivers/net/tun.c +++ b/drivers/net/tun.c @@ -657,7 +657,7 @@ static void __tun_detach(struct tun_file *tfile, bool clean) tun->dev->reg_state == NETREG_REGISTERED) unregister_netdevice(tun->dev); } - if (tun) + if (tfile->tx_array.ring.queue) skb_array_cleanup(&tfile->tx_array); sock_put(&tfile->sk); } @@ -2851,6 +2851,8 @@ static int tun_chr_open(struct inode *inode, struct file * file) sock_set_flag(&tfile->sk, SOCK_ZEROCOPY); + memset(&tfile->tx_array, 0, sizeof(tfile->tx_array)); + return 0; } -- 2.13.0