Revert "fib_rules: return 0 directly if an exactly same rule exists when NLM_F_EXCL not supplied"

This reverts commit e9919a24d3.

Nathan reported the new behaviour breaks Android, as Android just add
new rules and delete old ones.

If we return 0 without adding dup rules, Android will remove the new
added rules and causing system to soft-reboot.

Fixes: e9919a24d3 ("fib_rules: return 0 directly if an exactly same rule exists when NLM_F_EXCL not supplied")
Reported-by: Nathan Chancellor <natechancellor@gmail.com>
Reported-by: Yaro Slav <yaro330@gmail.com>
Reported-by: Maciej Żenczykowski <zenczykowski@gmail.com>
Signed-off-by: Hangbin Liu <liuhangbin@gmail.com>
Reviewed-by: Nathan Chancellor <natechancellor@gmail.com>
Tested-by: Nathan Chancellor <natechancellor@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Hangbin Liu 2019-06-05 12:27:14 +08:00 committed by David S. Miller
parent 930b9a0543
commit 4970b42d5c

View file

@ -757,9 +757,9 @@ int fib_nl_newrule(struct sk_buff *skb, struct nlmsghdr *nlh,
if (err)
goto errout;
if (rule_exists(ops, frh, tb, rule)) {
if (nlh->nlmsg_flags & NLM_F_EXCL)
err = -EEXIST;
if ((nlh->nlmsg_flags & NLM_F_EXCL) &&
rule_exists(ops, frh, tb, rule)) {
err = -EEXIST;
goto errout_free;
}