ipv4: Fix error return code in fib_table_insert()

stable inclusion
from stable-v5.10.157
commit aeebb074997251c150d042a33a8673bfea53c247
category: bugfix
bugzilla: https://gitee.com/openeuler/kernel/issues/I7MU59

Reference: https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/?id=aeebb074997251c150d042a33a8673bfea53c247



--------------------------------

[ Upstream commit 568fe849 ]

In fib_table_insert(), if the alias was already inserted, but node not
exist, the error code should be set before return from error handling path.

Fixes: a6c76c17 ("ipv4: Notify route after insertion to the routing table")
Signed-off-by: Ziyang Xuan <william.xuanziyang@huawei.com>
Link: https://lore.kernel.org/r/20221120072838.2167047-1-william.xuanziyang@huawei.com


Signed-off-by: Jakub Kicinski <kuba@kernel.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
Signed-off-by: sanglipeng <sanglipeng1@jd.com>