summaryrefslogtreecommitdiff
path: root/net/ipv4/fib_frontend.c
AgeCommit message (Collapse)Author
2025-05-20inet: Remove rtnl_is_held arg of lwtunnel_valid_encap_type(_attr)?().Kuniyuki Iwashima
Commit f130a0cc1b4f ("inet: fix lwtunnel_valid_encap_type() lock imbalance") added the rtnl_is_held argument as a temporary fix while I'm converting nexthop and IPv6 routing table to per-netns RTNL or RCU. Now all callers of lwtunnel_valid_encap_type() do not hold RTNL. Let's remove the argument. Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com> Link: https://patch.msgid.link/20250516022759.44392-3-kuniyu@amazon.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-04-16ipv4: Use nlmsg_payload in fib_frontend fileBreno Leitao
Leverage the new nlmsg_payload() helper to avoid checking for message size and then reading the nlmsg data. Signed-off-by: Breno Leitao <leitao@debian.org> Reviewed-by: Kuniyuki Iwashima <kuniyu@amazon.com> Link: https://patch.msgid.link/20250415-nlmsg_v2-v1-5-a1c75d493fd7@debian.org Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-03-05inet: fix lwtunnel_valid_encap_type() lock imbalanceEric Dumazet
After blamed commit rtm_to_fib_config() now calls lwtunnel_valid_encap_type{_attr}() without RTNL held, triggering an unlock balance in __rtnl_unlock, as reported by syzbot [1] IPv6 and rtm_to_nh_config() are not yet converted. Add a temporary @rtnl_is_held parameter to lwtunnel_valid_encap_type() and lwtunnel_valid_encap_type_attr(). While we are at it replace the two rcu_dereference() in lwtunnel_valid_encap_type() with more appropriate rcu_access_pointer(). [1] syz-executor245/5836 is trying to release lock (rtnl_mutex) at: [<ffffffff89d0e38c>] __rtnl_unlock+0x6c/0xf0 net/core/rtnetlink.c:142 but there are no more locks to release! other info that might help us debug this: no locks held by syz-executor245/5836. stack backtrace: CPU: 0 UID: 0 PID: 5836 Comm: syz-executor245 Not tainted 6.14.0-rc4-syzkaller-00873-g3424291dd242 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 02/12/2025 Call Trace: <TASK> __dump_stack lib/dump_stack.c:94 [inline] dump_stack_lvl+0x241/0x360 lib/dump_stack.c:120 print_unlock_imbalance_bug+0x25b/0x2d0 kernel/locking/lockdep.c:5289 __lock_release kernel/locking/lockdep.c:5518 [inline] lock_release+0x47e/0xa30 kernel/locking/lockdep.c:5872 __mutex_unlock_slowpath+0xec/0x800 kernel/locking/mutex.c:891 __rtnl_unlock+0x6c/0xf0 net/core/rtnetlink.c:142 lwtunnel_valid_encap_type+0x38a/0x5f0 net/core/lwtunnel.c:169 lwtunnel_valid_encap_type_attr+0x113/0x270 net/core/lwtunnel.c:209 rtm_to_fib_config+0x949/0x14e0 net/ipv4/fib_frontend.c:808 inet_rtm_newroute+0xf6/0x2a0 net/ipv4/fib_frontend.c:917 rtnetlink_rcv_msg+0x791/0xcf0 net/core/rtnetlink.c:6919 netlink_rcv_skb+0x206/0x480 net/netlink/af_netlink.c:2534 netlink_unicast_kernel net/netlink/af_netlink.c:1313 [inline] netlink_unicast+0x7f6/0x990 net/netlink/af_netlink.c:1339 netlink_sendmsg+0x8de/0xcb0 net/netlink/af_netlink.c:1883 sock_sendmsg_nosec net/socket.c:709 [inline] Fixes: 1dd2af7963e9 ("ipv4: fib: Convert RTM_NEWROUTE and RTM_DELROUTE to per-netns RTNL.") Reported-by: syzbot+3f18ef0f7df107a3f6a0@syzkaller.appspotmail.com Closes: https://lore.kernel.org/netdev/67c6f87a.050a0220.38b91b.0147.GAE@google.com/T/#u Signed-off-by: Eric Dumazet <edumazet@google.com> Reviewed-by: Kuniyuki Iwashima <kuniyu@amazon.com> Link: https://patch.msgid.link/20250304125918.2763514-1-edumazet@google.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-03-03ipv4: fib: Convert RTM_NEWROUTE and RTM_DELROUTE to per-netns RTNL.Kuniyuki Iwashima
We converted fib_info hash tables to per-netns one and now ready to convert RTM_NEWROUTE and RTM_DELROUTE to per-netns RTNL. Let's hold rtnl_net_lock() in inet_rtm_newroute() and inet_rtm_delroute(). Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Reviewed-by: David Ahern <dsahern@kernel.org> Link: https://patch.msgid.link/20250228042328.96624-13-kuniyu@amazon.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-03-03ipv4: fib: Move fib_valid_key_len() to rtm_to_fib_config().Kuniyuki Iwashima
fib_valid_key_len() is called in the beginning of fib_table_insert() or fib_table_delete() to check if the prefix length is valid. fib_table_insert() and fib_table_delete() are called from 3 paths - ip_rt_ioctl() - inet_rtm_newroute() / inet_rtm_delroute() - fib_magic() In the first ioctl() path, rtentry_to_fib_config() checks the prefix length with bad_mask(). Also, fib_magic() always passes the correct prefix: 32 or ifa->ifa_prefixlen, which is already validated. Let's move fib_valid_key_len() to the rtnetlink path, rtm_to_fib_config(). While at it, 2 direct returns in rtm_to_fib_config() are changed to goto to match other places in the same function Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Reviewed-by: David Ahern <dsahern@kernel.org> Link: https://patch.msgid.link/20250228042328.96624-12-kuniyu@amazon.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-03-03ipv4: fib: Hold rtnl_net_lock() in ip_rt_ioctl().Kuniyuki Iwashima
ioctl(SIOCADDRT/SIOCDELRT) calls ip_rt_ioctl() to add/remove a route in the netns of the specified socket. Let's hold rtnl_net_lock() there. Note that rtentry_to_fib_config() can be called without rtnl_net_lock() if we convert rtentry.dev handling to RCU later. Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Reviewed-by: David Ahern <dsahern@kernel.org> Link: https://patch.msgid.link/20250228042328.96624-11-kuniyu@amazon.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-03-03ipv4: fib: Hold rtnl_net_lock() for ip_fib_net_exit().Kuniyuki Iwashima
ip_fib_net_exit() requires RTNL and is called from fib_net_init() and fib_net_exit_batch(). Let's hold rtnl_net_lock() before ip_fib_net_exit(). Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Reviewed-by: David Ahern <dsahern@kernel.org> Link: https://patch.msgid.link/20250228042328.96624-10-kuniyu@amazon.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-03-03ipv4: fib: Allocate fib_info_hash[] during netns initialisation.Kuniyuki Iwashima
We will allocate fib_info_hash[] and fib_info_laddrhash[] for each netns. Currently, fib_info_hash[] is allocated when the first route is added. Let's move the first allocation to a new __net_init function. Note that we must call fib4_semantics_exit() in fib_net_exit_batch() because ->exit() is called earlier than ->exit_batch(). Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Reviewed-by: David Ahern <dsahern@kernel.org> Link: https://patch.msgid.link/20250228042328.96624-4-kuniyu@amazon.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2025-03-03ipv4: fib: Use cached net in fib_inetaddr_event().Kuniyuki Iwashima
net is available in fib_inetaddr_event(), let's use it. Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Reviewed-by: David Ahern <dsahern@kernel.org> Link: https://patch.msgid.link/20250228042328.96624-2-kuniyu@amazon.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-11-18net: ip: fix unexpected return in fib_validate_source()Menglong Dong
The errno should be replaced with drop reasons in fib_validate_source(), and the "-EINVAL" shouldn't be returned. And this causes a warning, which is reported by syzkaller: netlink: 'syz-executor371': attribute type 4 has an invalid length. ------------[ cut here ]------------ WARNING: CPU: 0 PID: 5842 at net/core/skbuff.c:1219 __sk_skb_reason_drop net/core/skbuff.c:1216 [inline] WARNING: CPU: 0 PID: 5842 at net/core/skbuff.c:1219 sk_skb_reason_drop+0x87/0x380 net/core/skbuff.c:1241 Modules linked in: CPU: 0 UID: 0 PID: 5842 Comm: syz-executor371 Not tainted 6.12.0-rc6-syzkaller-01362-ga58f00ed24b8 #0 Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 10/30/2024 RIP: 0010:__sk_skb_reason_drop net/core/skbuff.c:1216 [inline] RIP: 0010:sk_skb_reason_drop+0x87/0x380 net/core/skbuff.c:1241 Code: 00 00 00 fc ff df 41 8d 9e 00 00 fc ff bf 01 00 fc ff 89 de e8 ea 9f 08 f8 81 fb 00 00 fc ff 77 3a 4c 89 e5 e8 9a 9b 08 f8 90 <0f> 0b 90 eb 5e bf 01 00 00 00 89 ee e8 c8 9f 08 f8 85 ed 0f 8e 49 RSP: 0018:ffffc90003d57078 EFLAGS: 00010293 RAX: ffffffff898c3ec6 RBX: 00000000fffbffea RCX: ffff8880347a5a00 RDX: 0000000000000000 RSI: 00000000fffbffea RDI: 00000000fffc0001 RBP: dffffc0000000000 R08: ffffffff898c3eb6 R09: 1ffff110023eb7d4 R10: dffffc0000000000 R11: ffffed10023eb7d5 R12: dffffc0000000000 R13: ffff888011f5bdc0 R14: 00000000ffffffea R15: 0000000000000000 FS: 000055557d41e380(0000) GS:ffff8880b8600000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 000056519d31d608 CR3: 000000007854e000 CR4: 00000000003526f0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: <TASK> kfree_skb_reason include/linux/skbuff.h:1263 [inline] ip_rcv_finish_core+0xfde/0x1b50 net/ipv4/ip_input.c:424 ip_list_rcv_finish net/ipv4/ip_input.c:610 [inline] ip_sublist_rcv+0x3b1/0xab0 net/ipv4/ip_input.c:636 ip_list_rcv+0x42b/0x480 net/ipv4/ip_input.c:670 __netif_receive_skb_list_ptype net/core/dev.c:5715 [inline] __netif_receive_skb_list_core+0x94e/0x980 net/core/dev.c:5762 __netif_receive_skb_list net/core/dev.c:5814 [inline] netif_receive_skb_list_internal+0xa51/0xe30 net/core/dev.c:5905 netif_receive_skb_list+0x55/0x4b0 net/core/dev.c:5957 xdp_recv_frames net/bpf/test_run.c:280 [inline] xdp_test_run_batch net/bpf/test_run.c:361 [inline] bpf_test_run_xdp_live+0x1b5e/0x21b0 net/bpf/test_run.c:390 bpf_prog_test_run_xdp+0x805/0x11e0 net/bpf/test_run.c:1318 bpf_prog_test_run+0x2e4/0x360 kernel/bpf/syscall.c:4266 __sys_bpf+0x48d/0x810 kernel/bpf/syscall.c:5671 __do_sys_bpf kernel/bpf/syscall.c:5760 [inline] __se_sys_bpf kernel/bpf/syscall.c:5758 [inline] __x64_sys_bpf+0x7c/0x90 kernel/bpf/syscall.c:5758 do_syscall_x64 arch/x86/entry/common.c:52 [inline] do_syscall_64+0xf3/0x230 arch/x86/entry/common.c:83 entry_SYSCALL_64_after_hwframe+0x77/0x7f RIP: 0033:0x7f18af25a8e9 Code: ff c3 66 2e 0f 1f 84 00 00 00 00 00 0f 1f 44 00 00 48 89 f8 48 89 f7 48 89 d6 48 89 ca 4d 89 c2 4d 89 c8 4c 8b 4c 24 08 0f 05 <48> 3d 01 f0 ff ff 73 01 c3 48 c7 c1 b8 ff ff ff f7 d8 64 89 01 48 RSP: 002b:00007ffee4090af8 EFLAGS: 00000246 ORIG_RAX: 0000000000000141 RAX: ffffffffffffffda RBX: 0000000000000000 RCX: 00007f18af25a8e9 RDX: 0000000000000048 RSI: 0000000020000600 RDI: 000000000000000a RBP: 0000000000000000 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000246 R12: 0000000000000000 R13: 0000000000000000 R14: 0000000000000000 R15: 0000000000000000 Fix it by returning "-SKB_DROP_REASON_IP_LOCAL_SOURCE" instead of "-EINVAL" in fib_validate_source(). Reported-by: syzbot+52fbd90f020788ec7709@syzkaller.appspotmail.com Closes: https://lore.kernel.org/netdev/6738e539.050a0220.e1c64.0002.GAE@google.com/ Fixes: 82d9983ebeb8 ("net: ip: make ip_route_input_noref() return drop reasons") Signed-off-by: Menglong Dong <dongml2@chinatelecom.cn> Acked-by: Paolo Abeni <pabeni@redhat.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-11-12net: ip: make fib_validate_source() support drop reasonsMenglong Dong
In this commit, we make fib_validate_source() and __fib_validate_source() return -reason instead of errno on error. The return value of fib_validate_source can be -errno, 0, and 1. It's hard to make fib_validate_source() return drop reasons directly. The fib_validate_source() will return 1 if the scope of the source(revert) route is HOST. And the __mkroute_input() will mark the skb with IPSKB_DOREDIRECT in this case (combine with some other conditions). And then, a REDIRECT ICMP will be sent in ip_forward() if this flag exists. We can't pass this information to __mkroute_input if we make fib_validate_source() return drop reasons. Therefore, we introduce the wrapper fib_validate_source_reason() for fib_validate_source(), which will return the drop reasons on error. In the origin logic, LINUX_MIB_IPRPFILTER will be counted if fib_validate_source() return -EXDEV. And now, we need to adjust it by checking "reason == SKB_DROP_REASON_IP_RPFILTER". However, this will take effect only after the patch "net: ip: make ip_route_input_noref() return drop reasons", as we can't pass the drop reasons from fib_validate_source() to ip_rcv_finish_core() in this patch. Following new drop reasons are added in this patch: SKB_DROP_REASON_IP_LOCAL_SOURCE SKB_DROP_REASON_IP_INVALID_SOURCE Signed-off-by: Menglong Dong <dongml2@chinatelecom.cn> Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2024-10-29ipv4: Prepare fib_compute_spec_dst() to future .flowi4_tos conversion.Guillaume Nault
Use ip4h_dscp() to get the DSCP from the IPv4 header, then convert the dscp_t value to __u8 with inet_dscp_to_dsfield(). Then, when we'll convert .flowi4_tos to dscp_t, we'll just have to drop the inet_dscp_to_dsfield() call. Signed-off-by: Guillaume Nault <gnault@redhat.com> Reviewed-by: Ido Schimmel <idosch@nvidia.com> Link: https://patch.msgid.link/a0eba69cce94f747e4c7516184a85ffd0abbe3f0.1729530028.git.gnault@redhat.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-10-15ipv4: Use rtnl_register_many().Kuniyuki Iwashima
We will remove rtnl_register() in favour of rtnl_register_many(). When it succeeds, rtnl_register_many() guarantees all rtnetlink types in the passed array are supported, and there is no chance that a part of message types is not supported. Let's use rtnl_register_many() instead. Signed-off-by: Kuniyuki Iwashima <kuniyu@amazon.com> Reviewed-by: Eric Dumazet <edumazet@google.com> Link: https://patch.msgid.link/20241014201828.91221-7-kuniyu@amazon.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-10-09ipv4: Convert __fib_validate_source() to dscp_t.Guillaume Nault
Pass a dscp_t variable to __fib_validate_source(), instead of a plain u8, to prevent accidental setting of ECN bits in ->flowi4_tos. Only fib_validate_source() actually calls __fib_validate_source(). Since it already has a dscp_t variable to pass as parameter, we only need to remove the inet_dscp_to_dsfield() conversion. Signed-off-by: Guillaume Nault <gnault@redhat.com> Reviewed-by: Ido Schimmel <idosch@nvidia.com> Tested-by: Ido Schimmel <idosch@nvidia.com> Reviewed-by: David Ahern <dsahern@kernel.org> Link: https://patch.msgid.link/8206b0a64a21a208ed94774e261a251c8d7bc251.1728302212.git.gnault@redhat.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-10-09ipv4: Convert fib_validate_source() to dscp_t.Guillaume Nault
Pass a dscp_t variable to fib_validate_source(), instead of a plain u8, to prevent accidental setting of ECN bits in ->flowi4_tos. All callers of fib_validate_source() already have a dscp_t variable to pass as parameter. We just need to remove the inet_dscp_to_dsfield() conversions. Signed-off-by: Guillaume Nault <gnault@redhat.com> Reviewed-by: Ido Schimmel <idosch@nvidia.com> Tested-by: Ido Schimmel <idosch@nvidia.com> Reviewed-by: David Ahern <dsahern@kernel.org> Link: https://patch.msgid.link/08612a4519bc5a3578bb493fbaad82437ebb73dc.1728302212.git.gnault@redhat.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-08-22ipv4: Unmask upper DSCP bits in fib_compute_spec_dst()Ido Schimmel
As explained in commit 35ebf65e851c ("ipv4: Create and use fib_compute_spec_dst() helper."), the function is used - for example - to determine the source address for an ICMP reply. If we are responding to a multicast or broadcast packet, the source address is set to the source address that we would use if we were to send a packet to the unicast source of the original packet. This address is determined by performing a FIB lookup and using the preferred source address of the resulting route. Unmask the upper DSCP bits of the DS field of the packet that triggered the reply so that in the future the FIB lookup could be performed according to the full DSCP value. No functional changes intended since the upper DSCP bits are masked when comparing against the TOS selectors in FIB rules and routes. Signed-off-by: Ido Schimmel <idosch@nvidia.com> Reviewed-by: Guillaume Nault <gnault@redhat.com> Acked-by: Florian Westphal <fw@strlen.de> Reviewed-by: David Ahern <dsahern@kernel.org> Link: https://patch.msgid.link/20240821125251.1571445-8-idosch@nvidia.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-08-22ipv4: Unmask upper DSCP bits in NETLINK_FIB_LOOKUP familyIdo Schimmel
The NETLINK_FIB_LOOKUP netlink family can be used to perform a FIB lookup according to user provided parameters and communicate the result back to user space. Unmask the upper DSCP bits of the user-provided DS field before invoking the IPv4 FIB lookup API so that in the future the lookup could be performed according to the full DSCP value. No functional changes intended since the upper DSCP bits are masked when comparing against the TOS selectors in FIB rules and routes. Signed-off-by: Ido Schimmel <idosch@nvidia.com> Reviewed-by: Guillaume Nault <gnault@redhat.com> Acked-by: Florian Westphal <fw@strlen.de> Reviewed-by: David Ahern <dsahern@kernel.org> Link: https://patch.msgid.link/20240821125251.1571445-3-idosch@nvidia.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-08-20ipv4: Mask upper DSCP bits and ECN bits in NETLINK_FIB_LOOKUP familyIdo Schimmel
The NETLINK_FIB_LOOKUP netlink family can be used to perform a FIB lookup according to user provided parameters and communicate the result back to user space. However, unlike other users of the FIB lookup API, the upper DSCP bits and the ECN bits of the DS field are not masked, which can result in the wrong result being returned. Solve this by masking the upper DSCP bits and the ECN bits using IPTOS_RT_MASK. The structure that communicates the request and the response is not exported to user space, so it is unlikely that this netlink family is actually in use [1]. [1] https://lore.kernel.org/netdev/ZpqpB8vJU%2FQ6LSqa@debian/ Signed-off-by: Ido Schimmel <idosch@nvidia.com> Reviewed-by: Guillaume Nault <gnault@redhat.com> Signed-off-by: Paolo Abeni <pabeni@redhat.com>
2024-06-05rtnetlink: make the "split" NLM_DONE handling genericJakub Kicinski
Jaroslav reports Dell's OMSA Systems Management Data Engine expects NLM_DONE in a separate recvmsg(), both for rtnl_dump_ifinfo() and inet_dump_ifaddr(). We already added a similar fix previously in commit 460b0d33cf10 ("inet: bring NLM_DONE out to a separate recv() again") Instead of modifying all the dump handlers, and making them look different than modern for_each_netdev_dump()-based dump handlers - put the workaround in rtnetlink code. This will also help us move the custom rtnl-locking from af_netlink in the future (in net-next). Note that this change is not touching rtnl_dump_all(). rtnl_dump_all() is different kettle of fish and a potential problem. We now mix families in a single recvmsg(), but NLM_DONE is not coalesced. Tested: ./cli.py --dbg-small-recv 4096 --spec netlink/specs/rt_addr.yaml \ --dump getaddr --json '{"ifa-family": 2}' ./cli.py --dbg-small-recv 4096 --spec netlink/specs/rt_route.yaml \ --dump getroute --json '{"rtm-family": 2}' ./cli.py --dbg-small-recv 4096 --spec netlink/specs/rt_link.yaml \ --dump getlink Fixes: 3e41af90767d ("rtnetlink: use xarray iterator to implement rtnl_dump_ifinfo()") Fixes: cdb2f80f1c10 ("inet: use xa_array iterator to implement inet_dump_ifaddr()") Reported-by: Jaroslav Pulchart <jaroslav.pulchart@gooddata.com> Link: https://lore.kernel.org/all/CAK8fFZ7MKoFSEzMBDAOjoUt+vTZRRQgLDNXEOfdCCXSoXXKE0g@mail.gmail.com Signed-off-by: Jakub Kicinski <kuba@kernel.org> Reviewed-by: Eric Dumazet <edumazet@google.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2024-04-15inet: bring NLM_DONE out to a separate recv() againJakub Kicinski
Commit under Fixes optimized the number of recv() calls needed during RTM_GETROUTE dumps, but we got multiple reports of applications hanging on recv() calls. Applications expect that a route dump will be terminated with a recv() reading an individual NLM_DONE message. Coalescing NLM_DONE is perfectly legal in netlink, but even tho reporters fixed the code in respective projects, chances are it will take time for those applications to get updated. So revert to old behavior (for now)? Old kernel (5.19): $ ./cli.py --dbg-small-recv 4096 --spec netlink/specs/rt_route.yaml \ --dump getroute --json '{"rtm-family": 2}' Recv: read 692 bytes, 11 messages nl_len = 68 (52) nl_flags = 0x22 nl_type = 24 ... nl_len = 60 (44) nl_flags = 0x22 nl_type = 24 Recv: read 20 bytes, 1 messages nl_len = 20 (4) nl_flags = 0x2 nl_type = 3 Before (6.9-rc2): $ ./cli.py --dbg-small-recv 4096 --spec netlink/specs/rt_route.yaml \ --dump getroute --json '{"rtm-family": 2}' Recv: read 712 bytes, 12 messages nl_len = 68 (52) nl_flags = 0x22 nl_type = 24 ... nl_len = 60 (44) nl_flags = 0x22 nl_type = 24 nl_len = 20 (4) nl_flags = 0x2 nl_type = 3 After: $ ./cli.py --dbg-small-recv 4096 --spec netlink/specs/rt_route.yaml \ --dump getroute --json '{"rtm-family": 2}' Recv: read 692 bytes, 11 messages nl_len = 68 (52) nl_flags = 0x22 nl_type = 24 ... nl_len = 60 (44) nl_flags = 0x22 nl_type = 24 Recv: read 20 bytes, 1 messages nl_len = 20 (4) nl_flags = 0x2 nl_type = 3 Reported-by: Stefano Brivio <sbrivio@redhat.com> Link: https://lore.kernel.org/all/20240315124808.033ff58d@elisabeth Reported-by: Ilya Maximets <i.maximets@ovn.org> Link: https://lore.kernel.org/all/02b50aae-f0e9-47a4-8365-a977a85975d3@ovn.org Fixes: 4ce5dc9316de ("inet: switch inet_dump_fib() to RCU protection") Signed-off-by: Jakub Kicinski <kuba@kernel.org> Tested-by: Ilya Maximets <i.maximets@ovn.org> Reviewed-by: David Ahern <dsahern@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2024-03-07netlink: let core handle error cases in dump operationsEric Dumazet
After commit b5a899154aa9 ("netlink: handle EMSGSIZE errors in the core"), we can remove some code that was not 100 % correct anyway. Signed-off-by: Eric Dumazet <edumazet@google.com> Reviewed-by: Simon Horman <horms@kernel.org> Reviewed-by: Ido Schimmel <idosch@nvidia.com> Reviewed-by: David Ahern <dsahern@kernel.org> Link: https://lore.kernel.org/r/20240306102426.245689-1-edumazet@google.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2024-02-26inet: switch inet_dump_fib() to RCU protectionEric Dumazet
No longer hold RTNL while calling inet_dump_fib(). Also change return value for a completed dump: Returning 0 instead of skb->len allows NLMSG_DONE to be appended to the skb. User space does not have to call us again to get a standalone NLMSG_DONE marker. Signed-off-by: Eric Dumazet <edumazet@google.com> Reviewed-by: Donald Hunter <donald.hunter@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2024-02-26inet: allow ip_valid_fib_dump_req() to be called with RTNL or RCUEric Dumazet
Add a new field into struct fib_dump_filter, to let callers tell if they use RTNL locking or RCU. This is used in the following patch, when inet_dump_fib() no longer holds RTNL. Signed-off-by: Eric Dumazet <edumazet@google.com> Reviewed-by: Donald Hunter <donald.hunter@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2023-03-16ipv4: Fix incorrect table ID in IOCTL pathIdo Schimmel
Commit f96a3d74554d ("ipv4: Fix incorrect route flushing when source address is deleted") started to take the table ID field in the FIB info structure into account when determining if two structures are identical or not. This field is initialized using the 'fc_table' field in the route configuration structure, which is not set when adding a route via IOCTL. The above can result in user space being able to install two identical routes that only differ in the table ID field of their associated FIB info. Fix by initializing the table ID field in the route configuration structure in the IOCTL path. Before the fix: # ip route add default via 192.0.2.2 # route add default gw 192.0.2.2 # ip -4 r show default # default via 192.0.2.2 dev dummy10 # default via 192.0.2.2 dev dummy10 After the fix: # ip route add default via 192.0.2.2 # route add default gw 192.0.2.2 SIOCADDRT: File exists # ip -4 r show default default via 192.0.2.2 dev dummy10 Audited the code paths to ensure there are no other paths that do not properly initialize the route configuration structure when installing a route. Fixes: 5a56a0b3a45d ("net: Don't delete routes in different VRFs") Fixes: f96a3d74554d ("ipv4: Fix incorrect route flushing when source address is deleted") Reported-by: gaoxingwang <gaoxingwang1@huawei.com> Link: https://lore.kernel.org/netdev/20230314144159.2354729-1-gaoxingwang1@huawei.com/ Tested-by: gaoxingwang <gaoxingwang1@huawei.com> Signed-off-by: Ido Schimmel <idosch@nvidia.com> Reviewed-by: David Ahern <dsahern@kernel.org> Link: https://lore.kernel.org/r/20230315124009.4015212-1-idosch@nvidia.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-12-06ipv4: Fix incorrect route flushing when table ID 0 is usedIdo Schimmel
Cited commit added the table ID to the FIB info structure, but did not properly initialize it when table ID 0 is used. This can lead to a route in the default VRF with a preferred source address not being flushed when the address is deleted. Consider the following example: # ip address add dev dummy1 192.0.2.1/28 # ip address add dev dummy1 192.0.2.17/28 # ip route add 198.51.100.0/24 via 192.0.2.2 src 192.0.2.17 metric 100 # ip route add table 0 198.51.100.0/24 via 192.0.2.2 src 192.0.2.17 metric 200 # ip route show 198.51.100.0/24 198.51.100.0/24 via 192.0.2.2 dev dummy1 src 192.0.2.17 metric 100 198.51.100.0/24 via 192.0.2.2 dev dummy1 src 192.0.2.17 metric 200 Both routes are installed in the default VRF, but they are using two different FIB info structures. One with a metric of 100 and table ID of 254 (main) and one with a metric of 200 and table ID of 0. Therefore, when the preferred source address is deleted from the default VRF, the second route is not flushed: # ip address del dev dummy1 192.0.2.17/28 # ip route show 198.51.100.0/24 198.51.100.0/24 via 192.0.2.2 dev dummy1 src 192.0.2.17 metric 200 Fix by storing a table ID of 254 instead of 0 in the route configuration structure. Add a test case that fails before the fix: # ./fib_tests.sh -t ipv4_del_addr IPv4 delete address route tests Regular FIB info TEST: Route removed from VRF when source address deleted [ OK ] TEST: Route in default VRF not removed [ OK ] TEST: Route removed in default VRF when source address deleted [ OK ] TEST: Route in VRF is not removed by address delete [ OK ] Identical FIB info with different table ID TEST: Route removed from VRF when source address deleted [ OK ] TEST: Route in default VRF not removed [ OK ] TEST: Route removed in default VRF when source address deleted [ OK ] TEST: Route in VRF is not removed by address delete [ OK ] Table ID 0 TEST: Route removed in default VRF when source address deleted [FAIL] Tests passed: 8 Tests failed: 1 And passes after: # ./fib_tests.sh -t ipv4_del_addr IPv4 delete address route tests Regular FIB info TEST: Route removed from VRF when source address deleted [ OK ] TEST: Route in default VRF not removed [ OK ] TEST: Route removed in default VRF when source address deleted [ OK ] TEST: Route in VRF is not removed by address delete [ OK ] Identical FIB info with different table ID TEST: Route removed from VRF when source address deleted [ OK ] TEST: Route in default VRF not removed [ OK ] TEST: Route removed in default VRF when source address deleted [ OK ] TEST: Route in VRF is not removed by address delete [ OK ] Table ID 0 TEST: Route removed in default VRF when source address deleted [ OK ] Tests passed: 9 Tests failed: 0 Fixes: 5a56a0b3a45d ("net: Don't delete routes in different VRFs") Reported-by: Donald Sharp <sharpd@nvidia.com> Signed-off-by: Ido Schimmel <idosch@nvidia.com> Reviewed-by: David Ahern <dsahern@kernel.org> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-10-27Revert "ip: fix triggering of 'icmp redirect'"Nicolas Dichtel
This reverts commit eb55dc09b5dd040232d5de32812cc83001a23da6. The patch that introduces this bug is reverted right after this one. Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com> Reviewed-by: Julian Anastasov <ja@ssi.bg> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-08-31ip: fix triggering of 'icmp redirect'Nicolas Dichtel
__mkroute_input() uses fib_validate_source() to trigger an icmp redirect. My understanding is that fib_validate_source() is used to know if the src address and the gateway address are on the same link. For that, fib_validate_source() returns 1 (same link) or 0 (not the same network). __mkroute_input() is the only user of these positive values, all other callers only look if the returned value is negative. Since the below patch, fib_validate_source() didn't return anymore 1 when both addresses are on the same network, because the route lookup returns RT_SCOPE_LINK instead of RT_SCOPE_HOST. But this is, in fact, right. Let's adapat the test to return 1 again when both addresses are on the same link. CC: stable@vger.kernel.org Fixes: 747c14307214 ("ip: fix dflt addr selection for connected nexthop") Reported-by: kernel test robot <yujie.liu@intel.com> Reported-by: Heng Qi <hengqi@linux.alibaba.com> Signed-off-by: Nicolas Dichtel <nicolas.dichtel@6wind.com> Reviewed-by: David Ahern <dsahern@kernel.org> Link: https://lore.kernel.org/r/20220829100121.3821-1-nicolas.dichtel@6wind.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-04-30ipv4: remove unnecessary type castingsYu Zhe
remove unnecessary void* type castings. Signed-off-by: Yu Zhe <yuzhe@nfschina.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2022-03-15net: Add l3mdev index to flow struct and avoid oif reset for port devicesDavid Ahern
The fundamental premise of VRF and l3mdev core code is binding a socket to a device (l3mdev or netdev with an L3 domain) to indicate L3 scope. Legacy code resets flowi_oif to the l3mdev losing any original port device binding. Ben (among others) has demonstrated use cases where the original port device binding is important and needs to be retained. This patch handles that by adding a new entry to the common flow struct that can indicate the l3mdev index for later rule and table matching avoiding the need to reset flowi_oif. In addition to allowing more use cases that require port device binds, this patch brings a few datapath simplications: 1. l3mdev_fib_rule_match is only called when walking fib rules and always after l3mdev_update_flow. That allows an optimization to bail early for non-VRF type uses cases when flowi_l3mdev is not set. Also, only that index needs to be checked for the FIB table id. 2. l3mdev_update_flow can be called with flowi_oif set to a l3mdev (e.g., VRF) device. By resetting flowi_oif only for this case the FLOWI_FLAG_SKIP_NH_OIF flag is not longer needed and can be removed, removing several checks in the datapath. The flowi_iif path can be simplified to only be called if the it is not loopback (loopback can not be assigned to an L3 domain) and the l3mdev index is not already set. 3. Avoid another device lookup in the output path when the fib lookup returns a reject failure. Note: 2 functional tests for local traffic with reject fib rules are updated to reflect the new direct failure at FIB lookup time for ping rather than the failure on packet path. The current code fails like this: HINT: Fails since address on vrf device is out of device scope COMMAND: ip netns exec ns-A ping -c1 -w1 -I eth1 172.16.3.1 ping: Warning: source address might be selected on device other than: eth1 PING 172.16.3.1 (172.16.3.1) from 172.16.3.1 eth1: 56(84) bytes of data. --- 172.16.3.1 ping statistics --- 1 packets transmitted, 0 received, 100% packet loss, time 0ms where the test now directly fails: HINT: Fails since address on vrf device is out of device scope COMMAND: ip netns exec ns-A ping -c1 -w1 -I eth1 172.16.3.1 ping: connect: No route to host Signed-off-by: David Ahern <dsahern@kernel.org> Tested-by: Ben Greear <greearb@candelatech.com> Link: https://lore.kernel.org/r/20220314204551.16369-1-dsahern@kernel.org Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-02-21ipv4: Invalidate neighbour for broadcast address upon address additionIdo Schimmel
In case user space sends a packet destined to a broadcast address when a matching broadcast route is not configured, the kernel will create a unicast neighbour entry that will never be resolved [1]. When the broadcast route is configured, the unicast neighbour entry will not be invalidated and continue to linger, resulting in packets being dropped. Solve this by invalidating unresolved neighbour entries for broadcast addresses after routes for these addresses are internally configured by the kernel. This allows the kernel to create a broadcast neighbour entry following the next route lookup. Another possible solution that is more generic but also more complex is to have the ARP code register a listener to the FIB notification chain and invalidate matching neighbour entries upon the addition of broadcast routes. It is also possible to wave off the issue as a user space problem, but it seems a bit excessive to expect user space to be that intimately familiar with the inner workings of the FIB/neighbour kernel code. [1] https://lore.kernel.org/netdev/55a04a8f-56f3-f73c-2aea-2195923f09d1@huawei.com/ Reported-by: Wang Hai <wanghai38@huawei.com> Signed-off-by: Ido Schimmel <idosch@nvidia.com> Tested-by: Wang Hai <wanghai38@huawei.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2022-02-17Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netJakub Kicinski
No conflicts. Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-02-15ipv4: add description about martian sourceZhang Yunkai
When multiple containers are running in the environment and multiple macvlan network port are configured in each container, a lot of martian source prints will appear after martian_log is enabled. they are almost the same, and printed by net_warn_ratelimited. Each arp message will trigger this print on each network port. Such as: IPv4: martian source 173.254.95.16 from 173.254.100.109, on dev eth0 ll header: 00000000: ff ff ff ff ff ff 40 00 ad fe 64 6d 08 06 ......@...dm.. IPv4: martian source 173.254.95.16 from 173.254.100.109, on dev eth1 ll header: 00000000: ff ff ff ff ff ff 40 00 ad fe 64 6d 08 06 ......@...dm.. There is no description of this kind of source in the RFC1812. Signed-off-by: Zhang Yunkai <zhang.yunkai@zte.com.cn> Signed-off-by: David S. Miller <davem@davemloft.net>
2022-02-08ipv4: add fib_net_exit_batch()Eric Dumazet
cleanup_net() is competing with other rtnl users. Instead of acquiring rtnl at each fib_net_exit() invocation, add fib_net_exit_batch() so that rtnl is acquired once. Signed-off-by: Eric Dumazet <edumazet@google.com> Reviewed-by: David Ahern <dsahern@kernel.org> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-02-07ipv4: Reject routes specifying ECN bits in rtm_tosGuillaume Nault
Use the new dscp_t type to replace the fc_tos field of fib_config, to ensure IPv4 routes aren't influenced by ECN bits when configured with non-zero rtm_tos. Before this patch, IPv4 routes specifying an rtm_tos with some of the ECN bits set were accepted. However they wouldn't work (never match) as IPv4 normally clears the ECN bits with IPTOS_RT_MASK before doing a FIB lookup (although a few buggy code paths don't). After this patch, IPv4 routes specifying an rtm_tos with any ECN bit set is rejected. Note: IPv6 routes ignore rtm_tos altogether, any rtm_tos is accepted, but treated as if it were 0. Signed-off-by: Guillaume Nault <gnault@redhat.com> Acked-by: David Ahern <dsahern@kernel.org> Reviewed-by: Toke Høiland-Jørgensen <toke@redhat.com> Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-12-02ipv4: convert fib_num_tclassid_users to atomic_tEric Dumazet
Before commit faa041a40b9f ("ipv4: Create cleanup helper for fib_nh") changes to net->ipv4.fib_num_tclassid_users were protected by RTNL. After the change, this is no longer the case, as free_fib_info_rcu() runs after rcu grace period, without rtnl being held. Fixes: faa041a40b9f ("ipv4: Create cleanup helper for fib_nh") Signed-off-by: Eric Dumazet <edumazet@google.com> Cc: David Ahern <dsahern@kernel.org> Reviewed-by: David Ahern <dsahern@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-07-13net: Use nlmsg_unicast() instead of netlink_unicast()Yajun Deng
It has 'if (err >0 )' statement in nlmsg_unicast(), so use nlmsg_unicast() instead of netlink_unicast(), this looks more concise. v2: remove the change in netfilter. Signed-off-by: Yajun Deng <yajun.deng@linux.dev> Reviewed-by: David Ahern <dsahern@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-06-29Merge git://git.kernel.org/pub/scm/linux/kernel/git/netdev/netJakub Kicinski
Trivial conflict in net/netfilter/nf_tables_api.c. Duplicate fix in tools/testing/selftests/net/devlink_port_split.py - take the net-next version. skmsg, and L4 bpf - keep the bpf code but remove the flags and err params. Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-06-22net/ipv4: swap flow ports when validating sourceMiao Wang
When doing source address validation, the flowi4 struct used for fib_lookup should be in the reverse direction to the given skb. fl4_dport and fl4_sport returned by fib4_rules_early_flow_dissect should thus be swapped. Fixes: 5a847a6e1477 ("net/ipv4: Initialize proto and ports in flow struct") Signed-off-by: Miao Wang <shankerwangmiao@gmail.com> Reviewed-by: David Ahern <dsahern@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-05-18ipv4: Add a sysctl to control multipath hash fieldsIdo Schimmel
A subsequent patch will add a new multipath hash policy where the packet fields used for multipath hash calculation are determined by user space. This patch adds a sysctl that allows user space to set these fields. The packet fields are represented using a bitmask and are common between IPv4 and IPv6 to allow user space to use the same numbering across both protocols. For example, to hash based on standard 5-tuple: # sysctl -w net.ipv4.fib_multipath_hash_fields=0x0037 net.ipv4.fib_multipath_hash_fields = 0x0037 The kernel rejects unknown fields, for example: # sysctl -w net.ipv4.fib_multipath_hash_fields=0x1000 sysctl: setting key "net.ipv4.fib_multipath_hash_fields": Invalid argument More fields can be added in the future, if needed. Signed-off-by: Ido Schimmel <idosch@nvidia.com> Reviewed-by: David Ahern <dsahern@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2021-05-17ip: Treat IPv4 segment's lowest address as unicastSeth David Schoen
Treat only the highest, not the lowest, IPv4 address within a local subnet as a broadcast address. Signed-off-by: Seth David Schoen <schoen@loyalty.org> Suggested-by: John Gilmore <gnu@toad.com> Acked-by: Dave Taht <dave.taht@gmail.com> Reviewed-by: David Ahern <dsahern@kernel.org> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-12-28ipv4: Ignore ECN bits for fib lookups in fib_compute_spec_dst()Guillaume Nault
RT_TOS() only clears one of the ECN bits. Therefore, when fib_compute_spec_dst() resorts to a fib lookup, it can return different results depending on the value of the second ECN bit. For example, ECT(0) and ECT(1) packets could be treated differently. $ ip netns add ns0 $ ip netns add ns1 $ ip link add name veth01 netns ns0 type veth peer name veth10 netns ns1 $ ip -netns ns0 link set dev lo up $ ip -netns ns1 link set dev lo up $ ip -netns ns0 link set dev veth01 up $ ip -netns ns1 link set dev veth10 up $ ip -netns ns0 address add 192.0.2.10/24 dev veth01 $ ip -netns ns1 address add 192.0.2.11/24 dev veth10 $ ip -netns ns1 address add 192.0.2.21/32 dev lo $ ip -netns ns1 route add 192.0.2.10/32 tos 4 dev veth10 src 192.0.2.21 $ ip netns exec ns1 sysctl -wq net.ipv4.icmp_echo_ignore_broadcasts=0 With TOS 4 and ECT(1), ns1 replies using source address 192.0.2.21 (ping uses -Q to set all TOS and ECN bits): $ ip netns exec ns0 ping -c 1 -b -Q 5 192.0.2.255 [...] 64 bytes from 192.0.2.21: icmp_seq=1 ttl=64 time=0.544 ms But with TOS 4 and ECT(0), ns1 replies using source address 192.0.2.11 because the "tos 4" route isn't matched: $ ip netns exec ns0 ping -c 1 -b -Q 6 192.0.2.255 [...] 64 bytes from 192.0.2.11: icmp_seq=1 ttl=64 time=0.597 ms After this patch the ECN bits don't affect the result anymore: $ ip netns exec ns0 ping -c 1 -b -Q 6 192.0.2.255 [...] 64 bytes from 192.0.2.21: icmp_seq=1 ttl=64 time=0.591 ms Fixes: 35ebf65e851c ("ipv4: Create and use fib_compute_spec_dst() helper.") Signed-off-by: Guillaume Nault <gnault@redhat.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-12-04ipv4: fix error return code in rtm_to_fib_config()Zhang Changzhong
Fix to return a negative error code from the error handling case instead of 0, as done elsewhere in this function. Fixes: d15662682db2 ("ipv4: Allow ipv6 gateway with ipv4 routes") Reported-by: Hulk Robot <hulkci@huawei.com> Signed-off-by: Zhang Changzhong <zhangchangzhong@huawei.com> Reviewed-by: David Ahern <dsahern@kernel.org> Link: https://lore.kernel.org/r/1607071695-33740-1-git-send-email-zhangchangzhong@huawei.com Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2020-11-17ipv4: use IS_ENABLED instead of ifdefFlorian Klink
Checking for ifdef CONFIG_x fails if CONFIG_x=m. Use IS_ENABLED instead, which is true for both built-ins and modules. Otherwise, a > ip -4 route add 1.2.3.4/32 via inet6 fe80::2 dev eth1 fails with the message "Error: IPv6 support not enabled in kernel." if CONFIG_IPV6 is `m`. In the spirit of b8127113d01e53adba15b41aefd37b90ed83d631. Fixes: d15662682db2 ("ipv4: Allow ipv6 gateway with ipv4 routes") Cc: Kim Phillips <kim.phillips@arm.com> Signed-off-by: Florian Klink <flokli@flokli.de> Reviewed-by: David Ahern <dsahern@kernel.org> Link: https://lore.kernel.org/r/20201115224509.2020651-1-flokli@flokli.de Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2020-09-14ipv4: Initialize flowi4_multipath_hash in data pathDavid Ahern
flowi4_multipath_hash was added by the commit referenced below for tunnels. Unfortunately, the patch did not initialize the new field for several fast path lookups that do not initialize the entire flow struct to 0. Fix those locations. Currently, flowi4_multipath_hash is random garbage and affects the hash value computed by fib_multipath_hash for multipath selection. Fixes: 24ba14406c5c ("route: Add multipath_hash in flowi_common to make user-define hash") Signed-off-by: David Ahern <dsahern@gmail.com> Cc: wenxu <wenxu@ucloud.cn> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-05-26ipv4: nexthop version of fib_info_nh_uses_devDavid Ahern
Similar to the last path, need to fix fib_info_nh_uses_dev for external nexthops to avoid referencing multiple nh_grp structs. Move the device check in fib_info_nh_uses_dev to a helper and create a nexthop version that is called if the fib_info uses an external nexthop. Fixes: 430a049190de ("nexthop: Add support for nexthop groups") Signed-off-by: David Ahern <dsahern@gmail.com> Acked-by: Nikolay Aleksandrov <nikolay@cumulusnetworks.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-05-21net: don't return invalid table id error when we fall back to PF_UNSPECSabrina Dubroca
In case we can't find a ->dumpit callback for the requested (family,type) pair, we fall back to (PF_UNSPEC,type). In effect, we're in the same situation as if userspace had requested a PF_UNSPEC dump. For RTM_GETROUTE, that handler is rtnl_dump_all, which calls all the registered RTM_GETROUTE handlers. The requested table id may or may not exist for all of those families. commit ae677bbb4441 ("net: Don't return invalid table id error when dumping all families") fixed the problem when userspace explicitly requests a PF_UNSPEC dump, but missed the fallback case. For example, when we pass ipv6.disable=1 to a kernel with CONFIG_IP_MROUTE=y and CONFIG_IP_MROUTE_MULTIPLE_TABLES=y, the (PF_INET6, RTM_GETROUTE) handler isn't registered, so we end up in rtnl_dump_all, and listing IPv6 routes will unexpectedly print: # ip -6 r Error: ipv4: MR table does not exist. Dump terminated commit ae677bbb4441 introduced the dump_all_families variable, which gets set when userspace requests a PF_UNSPEC dump. However, we can't simply set the family to PF_UNSPEC in rtnetlink_rcv_msg in the fallback case to get dump_all_families == true, because some messages types (for example RTM_GETRULE and RTM_GETNEIGH) only register the PF_UNSPEC handler and use the family to filter in the kernel what is dumped to userspace. We would then export more entries, that userspace would have to filter. iproute does that, but other programs may not. Instead, this patch removes dump_all_families and updates the RTM_GETROUTE handlers to check if the family that is being dumped is their own. When it's not, which covers both the intentional PF_UNSPEC dumps (as dump_all_families did) and the fallback case, ignore the missing table id error. Fixes: cb167893f41e ("net: Plumb support for filtering ipv4 and ipv6 multicast route dumps") Signed-off-by: Sabrina Dubroca <sd@queasysnail.net> Reviewed-by: David Ahern <dsahern@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2020-03-23ipv4: fix a RCU-list lock in inet_dump_fib()Qian Cai
There is a place, inet_dump_fib() fib_table_dump fn_trie_dump_leaf() hlist_for_each_entry_rcu() without rcu_read_lock() will trigger a warning, WARNING: suspicious RCU usage ----------------------------- net/ipv4/fib_trie.c:2216 RCU-list traversed in non-reader section!! other info that might help us debug this: rcu_scheduler_active = 2, debug_locks = 1 1 lock held by ip/1923: #0: ffffffff8ce76e40 (rtnl_mutex){+.+.}, at: netlink_dump+0xd6/0x840 Call Trace: dump_stack+0xa1/0xea lockdep_rcu_suspicious+0x103/0x10d fn_trie_dump_leaf+0x581/0x590 fib_table_dump+0x15f/0x220 inet_dump_fib+0x4ad/0x5d0 netlink_dump+0x350/0x840 __netlink_dump_start+0x315/0x3e0 rtnetlink_rcv_msg+0x4d1/0x720 netlink_rcv_skb+0xf0/0x220 rtnetlink_rcv+0x15/0x20 netlink_unicast+0x306/0x460 netlink_sendmsg+0x44b/0x770 __sys_sendto+0x259/0x270 __x64_sys_sendto+0x80/0xa0 do_syscall_64+0x69/0xf4 entry_SYSCALL_64_after_hwframe+0x49/0xb3 Fixes: 18a8021a7be3 ("net/ipv4: Plumb support for filtering route dumps") Signed-off-by: Qian Cai <cai@lca.pw> Reviewed-by: David Ahern <dsahern@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-11-21ipv4: move fib4_has_custom_rules() helper to public headerPaolo Abeni
So that we can use it in the next patch. Additionally constify the helper argument. Suggested-by: David Ahern <dsahern@gmail.com> Signed-off-by: Paolo Abeni <pabeni@redhat.com> Reviewed-by: David Ahern <dsahern@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-10-26ipv4: fix route update on metric change.Paolo Abeni
Since commit af4d768ad28c ("net/ipv4: Add support for specifying metric of connected routes"), when updating an IP address with a different metric, the associated connected route is updated, too. Still, the mentioned commit doesn't handle properly some corner cases: $ ip addr add dev eth0 192.168.1.0/24 $ ip addr add dev eth0 192.168.2.1/32 peer 192.168.2.2 $ ip addr add dev eth0 192.168.3.1/24 $ ip addr change dev eth0 192.168.1.0/24 metric 10 $ ip addr change dev eth0 192.168.2.1/32 peer 192.168.2.2 metric 10 $ ip addr change dev eth0 192.168.3.1/24 metric 10 $ ip -4 route 192.168.1.0/24 dev eth0 proto kernel scope link src 192.168.1.0 192.168.2.2 dev eth0 proto kernel scope link src 192.168.2.1 192.168.3.0/24 dev eth0 proto kernel scope link src 192.168.2.1 metric 10 Only the last route is correctly updated. The problem is the current test in fib_modify_prefix_metric(): if (!(dev->flags & IFF_UP) || ifa->ifa_flags & (IFA_F_SECONDARY | IFA_F_NOPREFIXROUTE) || ipv4_is_zeronet(prefix) || prefix == ifa->ifa_local || ifa->ifa_prefixlen == 32) Which should be the logical 'not' of the pre-existing test in fib_add_ifaddr(): if (!ipv4_is_zeronet(prefix) && !(ifa->ifa_flags & IFA_F_SECONDARY) && (prefix != addr || ifa->ifa_prefixlen < 32)) To properly negate the original expression, we need to change the last logical 'or' to a logical 'and'. Fixes: af4d768ad28c ("net/ipv4: Add support for specifying metric of connected routes") Reported-and-suggested-by: Beniamino Galvani <bgalvani@redhat.com> Signed-off-by: Paolo Abeni <pabeni@redhat.com> Reviewed-by: David Ahern <dsahern@gmail.com> Signed-off-by: David S. Miller <davem@davemloft.net>
2019-08-09ipv4: Add lockdep condition to fix for_each_entry()Joel Fernandes (Google)
This commit applies the consolidated list_for_each_entry_rcu() support for lockdep conditions. Acked-by: David S. Miller <davem@davemloft.net> Signed-off-by: Joel Fernandes (Google) <joel@joelfernandes.org> Signed-off-by: Paul E. McKenney <paulmck@linux.ibm.com>