From 8d7924ce85bae64e7a67c366c7c50840f49f3a62 Mon Sep 17 00:00:00 2001 From: Pavel Skripkin Date: Sat, 17 Jul 2021 14:29:33 +0300 Subject: [PATCH] net: sched: fix memory leak in tcindex_partial_destroy_work [ Upstream commit f5051bcece50140abd1a11a2d36dc3ec5484fc32 ] Syzbot reported memory leak in tcindex_set_parms(). The problem was in non-freed perfect hash in tcindex_partial_destroy_work(). In tcindex_set_parms() new tcindex_data is allocated and some fields from old one are copied to new one, but not the perfect hash. Since tcindex_partial_destroy_work() is the destroy function for old tcindex_data, we need to free perfect hash to avoid memory leak. Reported-and-tested-by: syzbot+f0bbb2287b8993d4fa74@syzkaller.appspotmail.com Fixes: 331b72922c5f ("net: sched: RCU cls_tcindex") Signed-off-by: Pavel Skripkin Signed-off-by: David S. Miller Signed-off-by: Sasha Levin --- net/sched/cls_tcindex.c | 5 ++++- 1 file changed, 4 insertions(+), 1 deletion(-) diff --git a/net/sched/cls_tcindex.c b/net/sched/cls_tcindex.c index 3e81f87d0c89..684187a1fdb9 100644 --- a/net/sched/cls_tcindex.c +++ b/net/sched/cls_tcindex.c @@ -278,6 +278,8 @@ static int tcindex_filter_result_init(struct tcindex_filter_result *r, TCA_TCINDEX_POLICE); } +static void tcindex_free_perfect_hash(struct tcindex_data *cp); + static void tcindex_partial_destroy_work(struct work_struct *work) { struct tcindex_data *p = container_of(to_rcu_work(work), @@ -285,7 +287,8 @@ static void tcindex_partial_destroy_work(struct work_struct *work) rwork); rtnl_lock(); - kfree(p->perfect); + if (p->perfect) + tcindex_free_perfect_hash(p); kfree(p); rtnl_unlock(); }