From bd49916ee0f793cc25e9b501cc9dfef121146f51 Mon Sep 17 00:00:00 2001 From: Cong Wang Date: Mon, 11 Feb 2019 21:59:51 -0800 Subject: [PATCH] team: avoid complex list operations in team_nl_cmd_options_set() [ Upstream commit 2fdeee2549231b1f989f011bb18191f5660d3745 ] The current opt_inst_list operations inside team_nl_cmd_options_set() is too complex to track: LIST_HEAD(opt_inst_list); nla_for_each_nested(...) { list_for_each_entry(opt_inst, &team->option_inst_list, list) { if (__team_option_inst_tmp_find(&opt_inst_list, opt_inst)) continue; list_add(&opt_inst->tmp_list, &opt_inst_list); } } team_nl_send_event_options_get(team, &opt_inst_list); as while we retrieve 'opt_inst' from team->option_inst_list, it could be added to the local 'opt_inst_list' for multiple times. The __team_option_inst_tmp_find() doesn't work, as the setter team_mode_option_set() still calls team->ops.exit() which uses ->tmp_list too in __team_options_change_check(). Simplify the list operations by moving the 'opt_inst_list' and team_nl_send_event_options_get() into the nla_for_each_nested() loop so that it can be guranteed that we won't insert a same list entry for multiple times. Therefore, __team_option_inst_tmp_find() can be removed too. Fixes: 4fb0534fb7bb ("team: avoid adding twice the same option to the event list") Fixes: 2fcdb2c9e659 ("team: allow to send multiple set events in one message") Reported-by: syzbot+4d4af685432dc0e56c91@syzkaller.appspotmail.com Reported-by: syzbot+68ee510075cf64260cc4@syzkaller.appspotmail.com Cc: Jiri Pirko Cc: Paolo Abeni Signed-off-by: Cong Wang Acked-by: Jiri Pirko Reviewed-by: Paolo Abeni Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman --- drivers/net/team/team.c | 27 +++++---------------------- 1 file changed, 5 insertions(+), 22 deletions(-) diff --git a/drivers/net/team/team.c b/drivers/net/team/team.c index 33ffb573fd67..267a90423154 100644 --- a/drivers/net/team/team.c +++ b/drivers/net/team/team.c @@ -247,17 +247,6 @@ static void __team_option_inst_mark_removed_port(struct team *team, } } -static bool __team_option_inst_tmp_find(const struct list_head *opts, - const struct team_option_inst *needle) -{ - struct team_option_inst *opt_inst; - - list_for_each_entry(opt_inst, opts, tmp_list) - if (opt_inst == needle) - return true; - return false; -} - static int __team_options_register(struct team *team, const struct team_option *option, size_t option_count) @@ -2447,7 +2436,6 @@ static int team_nl_cmd_options_set(struct sk_buff *skb, struct genl_info *info) int err = 0; int i; struct nlattr *nl_option; - LIST_HEAD(opt_inst_list); team = team_nl_team_get(info); if (!team) @@ -2463,6 +2451,7 @@ static int team_nl_cmd_options_set(struct sk_buff *skb, struct genl_info *info) struct nlattr *opt_attrs[TEAM_ATTR_OPTION_MAX + 1]; struct nlattr *attr; struct nlattr *attr_data; + LIST_HEAD(opt_inst_list); enum team_option_type opt_type; int opt_port_ifindex = 0; /* != 0 for per-port options */ u32 opt_array_index = 0; @@ -2566,23 +2555,17 @@ static int team_nl_cmd_options_set(struct sk_buff *skb, struct genl_info *info) if (err) goto team_put; opt_inst->changed = true; - - /* dumb/evil user-space can send us duplicate opt, - * keep only the last one - */ - if (__team_option_inst_tmp_find(&opt_inst_list, - opt_inst)) - continue; - list_add(&opt_inst->tmp_list, &opt_inst_list); } if (!opt_found) { err = -ENOENT; goto team_put; } - } - err = team_nl_send_event_options_get(team, &opt_inst_list); + err = team_nl_send_event_options_get(team, &opt_inst_list); + if (err) + break; + } team_put: team_nl_team_put(team); -- 2.11.0