Commit 7c1a80e8 authored by Pavel Skripkin's avatar Pavel Skripkin Committed by Steffen Klassert
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net: xfrm: fix memory leak in xfrm_user_rcv_msg 



Syzbot reported memory leak in xfrm_user_rcv_msg(). The
problem was is non-freed skb's frag_list.

In skb_release_all() skb_release_data() will be called only
in case of skb->head != NULL, but netlink_skb_destructor()
sets head to NULL. So, allocated frag_list skb should be
freed manualy, since consume_skb() won't take care of it

Fixes: 5106f4a8 ("xfrm/compat: Add 32=>64-bit messages translator")
Reported-and-tested-by: default avatar <syzbot+fb347cf82c73a90efcca@syzkaller.appspotmail.com>
Signed-off-by: default avatarPavel Skripkin <paskripkin@gmail.com>
Signed-off-by: default avatarSteffen Klassert <steffen.klassert@secunet.com>
parent a118ff66

net/xfrm/xfrm_user.c

+10 −0
Original line number Diff line number Diff line
@@ -2811,6 +2811,16 @@ static int xfrm_user_rcv_msg(struct sk_buff *skb, struct nlmsghdr *nlh, 


	err = link->doit(skb, nlh, attrs);



	/* We need to free skb allocated in xfrm_alloc_compat() before

	 * returning from this function, because consume_skb() won't take

	 * care of frag_list since netlink destructor sets

	 * sbk->head to NULL. (see netlink_skb_destructor())

	 */

	if (skb_has_frag_list(skb)) {

		kfree_skb(skb_shinfo(skb)->frag_list);

		skb_shinfo(skb)->frag_list = NULL;

	}



err:

	kvfree(nlh64);

	return err;