net_sched: keep alloc_hash updated after hash allocation
In commit 599be01ee567 ("net_sched: fix an OOB access in cls_tcindex")
I moved cp->hash calculation before the first
tcindex_alloc_perfect_hash(), but cp->alloc_hash is left untouched.
This difference could lead to another out of bound access.
cp->alloc_hash should always be the size allocated, we should
update it after this tcindex_alloc_perfect_hash().
Reported-and-tested-by: syzbot+dcc34d54d68ef7d2d53d@syzkaller.appspotmail.com
Reported-and-tested-by: syzbot+c72da7b9ed57cde6fca2@syzkaller.appspotmail.com
Fixes: 599be01ee567 ("net_sched: fix an OOB access in cls_tcindex")
Cc: Jamal Hadi Salim <jhs@mojatatu.com>
Cc: Jiri Pirko <jiri@resnulli.us>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/sched/cls_tcindex.c b/net/sched/cls_tcindex.c
index f2cb24b..9904299 100644
--- a/net/sched/cls_tcindex.c
+++ b/net/sched/cls_tcindex.c
@@ -359,6 +359,7 @@
if (tcindex_alloc_perfect_hash(net, cp) < 0)
goto errout;
+ cp->alloc_hash = cp->hash;
for (i = 0; i < min(cp->hash, p->hash); i++)
cp->perfect[i].res = p->perfect[i].res;
balloc = 1;
