From: Hangbin Liu <liuhangbin@xxxxxxxxx> [ Upstream commit 4970b42d5c362bf873982db7d93245c5281e58f4 ] This reverts commit e9919a24d3022f72bcadc407e73a6ef17093a849. 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: e9919a24d302 ("fib_rules: return 0 directly if an exactly same rule exists when NLM_F_EXCL not supplied") Reported-by: Nathan Chancellor <natechancellor@xxxxxxxxx> Reported-by: Yaro Slav <yaro330@xxxxxxxxx> Reported-by: Maciej Żenczykowski <zenczykowski@xxxxxxxxx> Signed-off-by: Hangbin Liu <liuhangbin@xxxxxxxxx> Reviewed-by: Nathan Chancellor <natechancellor@xxxxxxxxx> Tested-by: Nathan Chancellor <natechancellor@xxxxxxxxx> Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- net/core/fib_rules.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) --- a/net/core/fib_rules.c +++ b/net/core/fib_rules.c @@ -563,9 +563,9 @@ int fib_nl_newrule(struct sk_buff *skb, rule->uid_range = fib_kuid_range_unset; } - 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; }