4.20-stable review patch. If anyone has any objections, please let me know.
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From: Cong Wang xiyou.wangcong@gmail.com
[ 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 jiri@resnulli.us Cc: Paolo Abeni pabeni@redhat.com Signed-off-by: Cong Wang xiyou.wangcong@gmail.com Acked-by: Jiri Pirko jiri@mellanox.com Reviewed-by: Paolo Abeni pabeni@redhat.com Signed-off-by: David S. Miller davem@davemloft.net Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- drivers/net/team/team.c | 27 +++++---------------------- 1 file changed, 5 insertions(+), 22 deletions(-)
--- a/drivers/net/team/team.c +++ b/drivers/net/team/team.c @@ -256,17 +256,6 @@ static void __team_option_inst_mark_remo } }
-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) @@ -2460,7 +2449,6 @@ static int team_nl_cmd_options_set(struc int err = 0; int i; struct nlattr *nl_option; - LIST_HEAD(opt_inst_list);
rtnl_lock();
@@ -2480,6 +2468,7 @@ static int team_nl_cmd_options_set(struc 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; @@ -2584,23 +2573,17 @@ static int team_nl_cmd_options_set(struc 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);