[PATCH][net-next] netfilter: ebtables: use array_size() helper in copy_{from,to}_user()
From: "Gustavo A. R. Silva" <gustavoars@kernel.org>
Date: 2021-09-28 20:02:48
Also in:
bridge, linux-hardening, lkml, netfilter-devel
Subsystem:
ethernet bridge, networking [general], the rest · Maintainers:
Nikolay Aleksandrov, Ido Schimmel, "David S. Miller", Eric Dumazet, Jakub Kicinski, Paolo Abeni, Linus Torvalds
Use array_size() helper instead of the open-coded version in
copy_{from,to}_user(). These sorts of multiplication factors
need to be wrapped in array_size().
Link: https://github.com/KSPP/linux/issues/160
Signed-off-by: Gustavo A. R. Silva <gustavoars@kernel.org>
---
net/bridge/netfilter/ebtables.c | 7 ++++---
1 file changed, 4 insertions(+), 3 deletions(-)
diff --git a/net/bridge/netfilter/ebtables.c b/net/bridge/netfilter/ebtables.c
index 83d1798dfbb4..32fa05ec4a6d 100644
--- a/net/bridge/netfilter/ebtables.c
+++ b/net/bridge/netfilter/ebtables.c@@ -1071,7 +1071,7 @@ static int do_replace_finish(struct net *net, struct ebt_replace *repl, */ if (repl->num_counters && copy_to_user(repl->counters, counterstmp, - repl->num_counters * sizeof(struct ebt_counter))) { + array_size(repl->num_counters, sizeof(struct ebt_counter)))) { /* Silent error, can't fail, new table is already in place */ net_warn_ratelimited("ebtables: counters copy to user failed while replacing table\n"); }
@@ -1399,7 +1399,8 @@ static int do_update_counters(struct net *net, const char *name, goto unlock_mutex; } - if (copy_from_user(tmp, counters, num_counters * sizeof(*counters))) { + if (copy_from_user(tmp, counters, + array_size(num_counters, sizeof(*counters)))) { ret = -EFAULT; goto unlock_mutex; }
@@ -1532,7 +1533,7 @@ static int copy_counters_to_user(struct ebt_table *t, write_unlock_bh(&t->lock); if (copy_to_user(user, counterstmp, - nentries * sizeof(struct ebt_counter))) + array_size(nentries, sizeof(struct ebt_counter)))) ret = -EFAULT; vfree(counterstmp); return ret;
--
2.27.0