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| author | Jason Wang <jasowang@redhat.com> | 2018-05-16 20:39:33 +0800 |
|---|---|---|
| committer | Greg Kroah-Hartman <gregkh@linuxfoundation.org> | 2018-09-19 22:43:48 +0200 |
| commit | daf0ca743b28050664c7bd03b6fb46a95d94d248 (patch) | |
| tree | 6152e4635bfb30662e5bfde108ca67b28dfdabee /drivers/net/tun.c | |
| parent | ab75811f71815092dc4f66e283b3851dbc989b2e (diff) | |
| download | linux-stable-daf0ca743b28050664c7bd03b6fb46a95d94d248.tar.gz linux-stable-daf0ca743b28050664c7bd03b6fb46a95d94d248.tar.bz2 linux-stable-daf0ca743b28050664c7bd03b6fb46a95d94d248.zip | |
tuntap: fix use after free during release
commit 7063efd33bb15abc0160347f89eb5aba6b7d000e upstream.
After commit b196d88aba8a ("tun: fix use after free for ptr_ring") we
need clean up tx ring during release(). But unfortunately, it tries to
do the cleanup blindly after socket were destroyed which will lead
another use-after-free. Fix this by doing the cleanup before dropping
the last reference of the socket in __tun_detach().
Backport Note :-
Upstream commit moves the ptr_ring_cleanup call from tun_chr_close to
__tun_detach. Upstream applied that patch after replacing skb_array with
ptr_ring. This patch moves the skb_array_cleanup call from
tun_chr_close to __tun_detach.
Reported-by: Andrei Vagin <avagin@virtuozzo.com>
Acked-by: Andrei Vagin <avagin@virtuozzo.com>
Fixes: b196d88aba8a ("tun: fix use after free for ptr_ring")
Signed-off-by: Jason Wang <jasowang@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Zubin Mithra <zsm@chromium.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/net/tun.c')
| -rw-r--r-- | drivers/net/tun.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/drivers/net/tun.c b/drivers/net/tun.c index 87a989be1cef..e0baea2dfd3c 100644 --- a/drivers/net/tun.c +++ b/drivers/net/tun.c @@ -575,6 +575,7 @@ static void __tun_detach(struct tun_file *tfile, bool clean) tun->dev->reg_state == NETREG_REGISTERED) unregister_netdevice(tun->dev); } + skb_array_cleanup(&tfile->tx_array); sock_put(&tfile->sk); } } @@ -2646,7 +2647,6 @@ static int tun_chr_close(struct inode *inode, struct file *file) struct tun_file *tfile = file->private_data; tun_detach(tfile, true); - skb_array_cleanup(&tfile->tx_array); return 0; } |