4.20-stable review patch. If anyone has any objections, please let me know.
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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 @@ -485,8 +485,10 @@ 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; }