[PATCH 4.9 30/32] igmp, mld: Fix memory leak in igmpv3/mld_del_delrec()

[Greg Kroah-Hartman]

4.9-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Hangbin Liu <liuhangbin@xxxxxxxxx>


[ Upstream commit 9c8bb163ae784be4f79ae504e78c862806087c54 ]

In function igmpv3/mld_add_delrec() we allocate pmc and put it in
idev->mc_tomb, so we should free it when we don't need it in del_delrec().
But I removed kfree(pmc) incorrectly in latest two patches. Now fix it.

Fixes: 24803f38a5c0 ("igmp: do not remove igmp souce list info when ...")
Fixes: 1666d49e1d41 ("mld: do not remove mld souce list info when ...")
Reported-by: Daniel Borkmann <daniel@xxxxxxxxxxxxx>
Signed-off-by: Hangbin Liu <liuhangbin@xxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
 net/ipv4/igmp.c  |    1 +
 net/ipv6/mcast.c |    1 +
 2 files changed, 2 insertions(+)

--- a/net/ipv4/igmp.c
+++ b/net/ipv4/igmp.c
@@ -1172,6 +1172,7 @@ static void igmpv3_del_delrec(struct in_
 				psf->sf_crcount = im->crcount;
 		}
 		in_dev_put(pmc->interface);
+		kfree(pmc);
 	}
 	spin_unlock_bh(&im->lock);
 }
--- a/net/ipv6/mcast.c
+++ b/net/ipv6/mcast.c
@@ -779,6 +779,7 @@ static void mld_del_delrec(struct inet6_
 				psf->sf_crcount = im->mca_crcount;
 		}
 		in6_dev_put(pmc->idev);
+		kfree(pmc);
 	}
 	spin_unlock_bh(&im->mca_lock);
 }