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| author | Eric Dumazet <edumazet@google.com> | 2026-05-20 11:42:07 +0000 |
|---|---|---|
| committer | Jakub Kicinski <kuba@kernel.org> | 2026-05-21 08:47:36 -0700 |
| commit | bdd39576bf50a50bdafe3da968fd271bc674a48f (patch) | |
| tree | 954a8af35f5ba12cd463ea3e46f9e7942050930d /net/core | |
| parent | 979c017803c40829b03acd9e5236e354b7622360 (diff) | |
| download | lwn-bdd39576bf50a50bdafe3da968fd271bc674a48f.tar.gz lwn-bdd39576bf50a50bdafe3da968fd271bc674a48f.zip | |
net: bridge: prevent too big nested attributes in br_fill_linkxstats()
After commit ff205bf8c554 ("netlink: add one debug check in nla_nest_end()")
syzbot found that br_fill_linkxstats() can send corrupted netlink packets.
Make sure the nested attribute size is bounded.
Fixes: a60c090361ea ("bridge: netlink: export per-vlan stats")
Reported-by: syzbot+a35f9259d08f907c06e6@syzkaller.appspotmail.com
Closes: https://lore.kernel.org/netdev/6a0b0da3.050a0220.175f0c.0000.GAE@google.com/
Signed-off-by: Eric Dumazet <edumazet@google.com>
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Acked-by: Nikolay Aleksandrov <razor@blackwall.org>
Link: https://patch.msgid.link/20260520114207.1394241-1-edumazet@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Diffstat (limited to 'net/core')
| -rw-r--r-- | net/core/rtnetlink.c | 5 |
1 files changed, 3 insertions, 2 deletions
diff --git a/net/core/rtnetlink.c b/net/core/rtnetlink.c index df042da422ef..511c25bf6f2a 100644 --- a/net/core/rtnetlink.c +++ b/net/core/rtnetlink.c @@ -6328,8 +6328,9 @@ static int rtnl_stats_get(struct sk_buff *skb, struct nlmsghdr *nlh, NETLINK_CB(skb).portid, nlh->nlmsg_seq, 0, 0, &filters, &idxattr, &prividx, extack); if (err < 0) { - /* -EMSGSIZE implies BUG in if_nlmsg_stats_size */ - WARN_ON(err == -EMSGSIZE); + /* -EMSGSIZE implies BUG in if_nlmsg_stats_size + * or a too big nested attribute. + */ kfree_skb(nskb); } else { err = rtnl_unicast(nskb, net, NETLINK_CB(skb).portid); |