| From foo@baz Fri Jan 4 20:27:35 CET 2019 |
| From: Cong Wang <xiyou.wangcong@gmail.com> |
| Date: Sat, 29 Dec 2018 13:56:37 -0800 |
| Subject: net/wan: fix a double free in x25_asy_open_tty() |
| |
| From: Cong Wang <xiyou.wangcong@gmail.com> |
| |
| [ Upstream commit d5c7c745f254c6cb98b3b3f15fe789b8bd770c72 ] |
| |
| When x25_asy_open() fails, it already cleans up by itself, |
| so its caller doesn't need to free the memory again. |
| |
| It seems we still have to call x25_asy_free() to clear the SLF_INUSE |
| bit, so just set these pointers to NULL after kfree(). |
| |
| Reported-and-tested-by: syzbot+5e5e969e525129229052@syzkaller.appspotmail.com |
| Fixes: 3b780bed3138 ("x25_asy: Free x25_asy on x25_asy_open() failure.") |
| Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com> |
| Signed-off-by: David S. Miller <davem@davemloft.net> |
| Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> |
| --- |
| drivers/net/wan/x25_asy.c | 2 ++ |
| 1 file changed, 2 insertions(+) |
| |
| --- a/drivers/net/wan/x25_asy.c |
| +++ b/drivers/net/wan/x25_asy.c |
| @@ -488,8 +488,10 @@ static int x25_asy_open(struct net_devic |
| |
| /* Cleanup */ |
| kfree(sl->xbuff); |
| + sl->xbuff = NULL; |
| noxbuff: |
| kfree(sl->rbuff); |
| + sl->rbuff = NULL; |
| norbuff: |
| return -ENOMEM; |
| } |
