Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
ipv6: Split ip6_route_info_create().
We will get rid of RTNL from RTM_NEWROUTE and SIOCADDRT and rely
on RCU to guarantee dev and nexthop lifetime.
Then, we want to allocate as much as possible before entering
the RCU section.
The RCU section will start in the middle of ip6_route_info_create(),
and this is problematic for ip6_route_multipath_add() that calls
ip6_route_info_create() multiple times.
Let's split ip6_route_info_create() into two parts; one for memory
allocation and another for nexthop setup.
Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Acked-by: Paolo Abeni <pabeni@redhat.com>
Link: https://patch.msgid.link/20250418000443.43734-7-kuniyu@amazon.com
Signed-off-by: Paolo Abeni <pabeni@redhat.com>
authored by
Kuniyuki Iwashima
and committed by
Paolo Abeni
c4837b98
c9cabe05
+62
-33
+62
-33
net/ipv6/route.c
+62
-33
net/ipv6/route.c
···
3729
3729
}
3730
3730
3731
3731
static struct fib6_info *ip6_route_info_create(struct fib6_config *cfg,
3732
-
gfp_t gfp_flags,
3733
-
struct netlink_ext_ack *extack)
3732
+
gfp_t gfp_flags,
3733
+
struct netlink_ext_ack *extack)
3734
3734
{
3735
3735
struct net *net = cfg->fc_nlinfo.nl_net;
3736
-
struct fib6_info *rt = NULL;
3737
3736
struct fib6_table *table;
3738
-
struct fib6_nh *fib6_nh;
3739
-
int err = -ENOBUFS;
3740
-
int addr_type;
3737
+
struct fib6_info *rt;
3738
+
int err;
3741
3739
3742
3740
if (cfg->fc_nlinfo.nlh &&
3743
3741
!(cfg->fc_nlinfo.nlh->nlmsg_flags & NLM_F_CREATE)) {
···
3747
3749
} else {
3748
3750
table = fib6_new_table(net, cfg->fc_table);
3749
3751
}
3752
+
if (!table) {
3753
+
err = -ENOBUFS;
3754
+
goto err;
3755
+
}
3750
3756
3751
-
if (!table)
3752
-
goto out;
3753
-
3754
-
err = -ENOMEM;
3755
3757
rt = fib6_info_alloc(gfp_flags, !cfg->fc_nh_id);
3756
-
if (!rt)
3757
-
goto out;
3758
+
if (!rt) {
3759
+
err = -ENOMEM;
3760
+
goto err;
3761
+
}
3758
3762
3759
3763
rt->fib6_metrics = ip_fib_metrics_init(cfg->fc_mx, cfg->fc_mx_len,
3760
3764
extack);
3761
3765
if (IS_ERR(rt->fib6_metrics)) {
3762
3766
err = PTR_ERR(rt->fib6_metrics);
3763
-
/* Do not leave garbage there. */
3764
-
rt->fib6_metrics = (struct dst_metrics *)&dst_default_metrics;
3765
-
goto out_free;
3767
+
goto free;
3766
3768
}
3767
3769
3768
3770
if (cfg->fc_flags & RTF_ADDRCONF)
···
3770
3772
3771
3773
if (cfg->fc_flags & RTF_EXPIRES)
3772
3774
fib6_set_expires(rt, jiffies +
3773
-
clock_t_to_jiffies(cfg->fc_expires));
3775
+
clock_t_to_jiffies(cfg->fc_expires));
3774
3776
3775
3777
if (cfg->fc_protocol == RTPROT_UNSPEC)
3776
3778
cfg->fc_protocol = RTPROT_BOOT;
3777
-
rt->fib6_protocol = cfg->fc_protocol;
3778
3779
3780
+
rt->fib6_protocol = cfg->fc_protocol;
3779
3781
rt->fib6_table = table;
3780
3782
rt->fib6_metric = cfg->fc_metric;
3781
3783
rt->fib6_type = cfg->fc_type ? : RTN_UNICAST;
···
3788
3790
ipv6_addr_prefix(&rt->fib6_src.addr, &cfg->fc_src, cfg->fc_src_len);
3789
3791
rt->fib6_src.plen = cfg->fc_src_len;
3790
3792
#endif
3793
+
return rt;
3794
+
free:
3795
+
kfree(rt);
3796
+
err:
3797
+
return ERR_PTR(err);
3798
+
}
3799
+
3800
+
static int ip6_route_info_create_nh(struct fib6_info *rt,
3801
+
struct fib6_config *cfg,
3802
+
struct netlink_ext_ack *extack)
3803
+
{
3804
+
struct net *net = cfg->fc_nlinfo.nl_net;
3805
+
struct fib6_nh *fib6_nh;
3806
+
int err;
3791
3807
3792
3808
if (cfg->fc_nh_id) {
3793
3809
struct nexthop *nh;
···
3826
3814
rt->nh = nh;
3827
3815
fib6_nh = nexthop_fib6_nh(rt->nh);
3828
3816
} else {
3829
-
err = fib6_nh_init(net, rt->fib6_nh, cfg, gfp_flags, extack);
3817
+
int addr_type;
3818
+
3819
+
err = fib6_nh_init(net, rt->fib6_nh, cfg, GFP_ATOMIC, extack);
3830
3820
if (err)
3831
-
goto out;
3821
+
goto out_release;
3832
3822
3833
3823
fib6_nh = rt->fib6_nh;
3834
3824
···
3849
3835
if (!ipv6_chk_addr(net, &cfg->fc_prefsrc, dev, 0)) {
3850
3836
NL_SET_ERR_MSG(extack, "Invalid source address");
3851
3837
err = -EINVAL;
3852
-
goto out;
3838
+
goto out_release;
3853
3839
}
3854
3840
rt->fib6_prefsrc.addr = cfg->fc_prefsrc;
3855
3841
rt->fib6_prefsrc.plen = 128;
3856
-
} else
3857
-
rt->fib6_prefsrc.plen = 0;
3842
+
}
3858
3843
3859
-
return rt;
3860
-
out:
3844
+
return 0;
3845
+
out_release:
3861
3846
fib6_info_release(rt);
3862
-
return ERR_PTR(err);
3847
+
return err;
3863
3848
out_free:
3864
3849
ip_fib_metrics_put(rt->fib6_metrics);
3865
3850
kfree(rt);
3866
-
return ERR_PTR(err);
3851
+
return err;
3867
3852
}
3868
3853
3869
3854
int ip6_route_add(struct fib6_config *cfg, gfp_t gfp_flags,
···
3874
3861
rt = ip6_route_info_create(cfg, gfp_flags, extack);
3875
3862
if (IS_ERR(rt))
3876
3863
return PTR_ERR(rt);
3864
+
3865
+
err = ip6_route_info_create_nh(rt, cfg, extack);
3866
+
if (err)
3867
+
return err;
3877
3868
3878
3869
err = __ip6_ins_rt(rt, &cfg->fc_nlinfo, extack);
3879
3870
fib6_info_release(rt);
···
4602
4585
.fc_ignore_dev_down = true,
4603
4586
};
4604
4587
struct fib6_info *f6i;
4588
+
int err;
4605
4589
4606
4590
if (anycast) {
4607
4591
cfg.fc_type = RTN_ANYCAST;
···
4613
4595
}
4614
4596
4615
4597
f6i = ip6_route_info_create(&cfg, gfp_flags, extack);
4616
-
if (!IS_ERR(f6i)) {
4617
-
f6i->dst_nocount = true;
4598
+
if (IS_ERR(f6i))
4599
+
return f6i;
4618
4600
4619
-
if (!anycast &&
4620
-
(READ_ONCE(net->ipv6.devconf_all->disable_policy) ||
4621
-
READ_ONCE(idev->cnf.disable_policy)))
4622
-
f6i->dst_nopolicy = true;
4623
-
}
4601
+
err = ip6_route_info_create_nh(f6i, &cfg, extack);
4602
+
if (err)
4603
+
return ERR_PTR(err);
4604
+
4605
+
f6i->dst_nocount = true;
4606
+
4607
+
if (!anycast &&
4608
+
(READ_ONCE(net->ipv6.devconf_all->disable_policy) ||
4609
+
READ_ONCE(idev->cnf.disable_policy)))
4610
+
f6i->dst_nopolicy = true;
4624
4611
4625
4612
return f6i;
4626
4613
}
···
5419
5396
rt = ip6_route_info_create(&r_cfg, GFP_KERNEL, extack);
5420
5397
if (IS_ERR(rt)) {
5421
5398
err = PTR_ERR(rt);
5399
+
rt = NULL;
5400
+
goto cleanup;
5401
+
}
5402
+
5403
+
err = ip6_route_info_create_nh(rt, &r_cfg, extack);
5404
+
if (err) {
5422
5405
rt = NULL;
5423
5406
goto cleanup;
5424
5407
}