[PATCH net v2 0/2] net: ipv4: fix nexthop route delete warning

[PATCH net v2 0/2] net: ipv4: fix nexthop route delete warning

[Nikolay Aleksandrov]

Hi,
The first patch fixes a warning that can be triggered by deleting a
nexthop route and specifying a device (more info in its commit msg).
And the second patch adds a selftest for that case.

Chose this way to fix it because we should match when deleting without
nh spec and should fail when deleting a nexthop route with old-style nh
spec because nexthop objects are managed separately, e.g.:
$ ip r show 1.2.3.4/32
1.2.3.4 nhid 12 via 192.168.11.2 dev dummy0 

$ ip r del 1.2.3.4/32
$ ip r del 1.2.3.4/32 nhid 12
<both should work>

$ ip r del 1.2.3.4/32 dev dummy0
<should fail with ESRCH>

v2: addded more to patch 01's commit message
    adjusted the test comment in patch 02

Thanks,
 Nik

Nikolay Aleksandrov (2):
  net: ipv4: fix route with nexthop object delete warning
  selftests: net: add delete nexthop route warning test

 net/ipv4/fib_semantics.c                    |  7 ++++++-
 tools/testing/selftests/net/fib_nexthops.sh | 14 ++++++++++++++
 2 files changed, 20 insertions(+), 1 deletion(-)

-- 
2.35.1

[PATCH net v2 1/2] net: ipv4: fix route with nexthop object delete warning

[Nikolay Aleksandrov]

FRR folks have hit a kernel warning[1] while deleting routes[2] which is
caused by trying to delete a route pointing to a nexthop id without
specifying nhid but matching on an interface. That is, a route is found
but we hit a warning while matching it. The warning is from
fib_info_nh() in include/net/nexthop.h because we run it on a fib_info
with nexthop object. The call chain is:
 inet_rtm_delroute -> fib_table_delete -> fib_nh_match (called with a
nexthop fib_info and also with fc_oif set thus calling fib_info_nh on
the fib_info and triggering the warning). The fix is to not do any
matching in that branch if the fi has a nexthop object because those are
managed separately. I.e. we should match when deleting without nh spec and
should fail when deleting a nexthop route with old-style nh spec because
nexthop objects are managed separately, e.g.:
 $ ip r show 1.2.3.4/32
 1.2.3.4 nhid 12 via 192.168.11.2 dev dummy0 

 $ ip r del 1.2.3.4/32
 $ ip r del 1.2.3.4/32 nhid 12
 <both should work>

 $ ip r del 1.2.3.4/32 dev dummy0
 <should fail with ESRCH>

[1]
 [  523.462226] ------------[ cut here ]------------
 [  523.462230] WARNING: CPU: 14 PID: 22893 at include/net/nexthop.h:468 fib_nh_match+0x210/0x460
 [  523.462236] Modules linked in: dummy rpcsec_gss_krb5 xt_socket nf_socket_ipv4 nf_socket_ipv6 ip6table_raw iptable_raw bpf_preload xt_statistic ip_set ip_vs_sh ip_vs_wrr ip_vs_rr ip_vs xt_mark nf_tables xt_nat veth nf_conntrack_netlink nfnetlink xt_addrtype br_netfilter overlay dm_crypt nfsv3 nfs fscache netfs vhost_net vhost vhost_iotlb tap tun xt_CHECKSUM xt_MASQUERADE xt_conntrack 8021q garp mrp ipt_REJECT nf_reject_ipv4 ip6table_mangle ip6table_nat iptable_mangle iptable_nat nf_nat nf_conntrack nf_defrag_ipv6 nf_defrag_ipv4 iptable_filter bridge stp llc rfcomm snd_seq_dummy snd_hrtimer rpcrdma rdma_cm iw_cm ib_cm ib_core ip6table_filter xt_comment ip6_tables vboxnetadp(OE) vboxnetflt(OE) vboxdrv(OE) qrtr bnep binfmt_misc xfs vfat fat squashfs loop nvidia_drm(POE) nvidia_modeset(POE) nvidia_uvm(POE) nvidia(POE) intel_rapl_msr intel_rapl_common snd_hda_codec_realtek snd_hda_codec_generic ledtrig_audio snd_hda_codec_hdmi btusb btrtl iwlmvm uvcvideo btbcm snd_hda_intel edac_mce_amd
 [  523.462274]  videobuf2_vmalloc videobuf2_memops btintel snd_intel_dspcfg videobuf2_v4l2 snd_intel_sdw_acpi bluetooth snd_usb_audio snd_hda_codec mac80211 snd_usbmidi_lib joydev snd_hda_core videobuf2_common kvm_amd snd_rawmidi snd_hwdep snd_seq videodev ccp snd_seq_device libarc4 ecdh_generic mc snd_pcm kvm iwlwifi snd_timer drm_kms_helper snd cfg80211 cec soundcore irqbypass rapl wmi_bmof i2c_piix4 rfkill k10temp pcspkr acpi_cpufreq nfsd auth_rpcgss nfs_acl lockd grace sunrpc drm zram ip_tables crct10dif_pclmul crc32_pclmul crc32c_intel ghash_clmulni_intel nvme sp5100_tco r8169 nvme_core wmi ipmi_devintf ipmi_msghandler fuse
 [  523.462300] CPU: 14 PID: 22893 Comm: ip Tainted: P           OE     5.16.18-200.fc35.x86_64 #1
 [  523.462302] Hardware name: Micro-Star International Co., Ltd. MS-7C37/MPG X570 GAMING EDGE WIFI (MS-7C37), BIOS 1.C0 10/29/2020
 [  523.462303] RIP: 0010:fib_nh_match+0x210/0x460
 [  523.462304] Code: 7c 24 20 48 8b b5 90 00 00 00 e8 bb ee f4 ff 48 8b 7c 24 20 41 89 c4 e8 ee eb f4 ff 45 85 e4 0f 85 2e fe ff ff e9 4c ff ff ff <0f> 0b e9 17 ff ff ff 3c 0a 0f 85 61 fe ff ff 48 8b b5 98 00 00 00
 [  523.462306] RSP: 0018:ffffaa53d4d87928 EFLAGS: 00010286
 [  523.462307] RAX: 0000000000000000 RBX: ffffaa53d4d87a90 RCX: ffffaa53d4d87bb0
 [  523.462308] RDX: ffff9e3d2ee6be80 RSI: ffffaa53d4d87a90 RDI: ffffffff920ed380
 [  523.462309] RBP: ffff9e3d2ee6be80 R08: 0000000000000064 R09: 0000000000000000
 [  523.462310] R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000031
 [  523.462310] R13: 0000000000000020 R14: 0000000000000000 R15: ffff9e3d331054e0
 [  523.462311] FS:  00007f245517c1c0(0000) GS:ffff9e492ed80000(0000) knlGS:0000000000000000
 [  523.462313] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
 [  523.462313] CR2: 000055e5dfdd8268 CR3: 00000003ef488000 CR4: 0000000000350ee0
 [  523.462315] Call Trace:
 [  523.462316]  <TASK>
 [  523.462320]  fib_table_delete+0x1a9/0x310
 [  523.462323]  inet_rtm_delroute+0x93/0x110
 [  523.462325]  rtnetlink_rcv_msg+0x133/0x370
 [  523.462327]  ? _copy_to_iter+0xb5/0x6f0
 [  523.462330]  ? rtnl_calcit.isra.0+0x110/0x110
 [  523.462331]  netlink_rcv_skb+0x50/0xf0
 [  523.462334]  netlink_unicast+0x211/0x330
 [  523.462336]  netlink_sendmsg+0x23f/0x480
 [  523.462338]  sock_sendmsg+0x5e/0x60
 [  523.462340]  ____sys_sendmsg+0x22c/0x270
 [  523.462341]  ? import_iovec+0x17/0x20
 [  523.462343]  ? sendmsg_copy_msghdr+0x59/0x90
 [  523.462344]  ? __mod_lruvec_page_state+0x85/0x110
 [  523.462348]  ___sys_sendmsg+0x81/0xc0
 [  523.462350]  ? netlink_seq_start+0x70/0x70
 [  523.462352]  ? __dentry_kill+0x13a/0x180
 [  523.462354]  ? __fput+0xff/0x250
 [  523.462356]  __sys_sendmsg+0x49/0x80
 [  523.462358]  do_syscall_64+0x3b/0x90
 [  523.462361]  entry_SYSCALL_64_after_hwframe+0x44/0xae
 [  523.462364] RIP: 0033:0x7f24552aa337
 [  523.462365] Code: 0e 00 f7 d8 64 89 02 48 c7 c0 ff ff ff ff eb b9 0f 1f 00 f3 0f 1e fa 64 8b 04 25 18 00 00 00 85 c0 75 10 b8 2e 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 51 c3 48 83 ec 28 89 54 24 1c 48 89 74 24 10
 [  523.462366] RSP: 002b:00007fff7f05a838 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
 [  523.462368] RAX: ffffffffffffffda RBX: 000000006245bf91 RCX: 00007f24552aa337
 [  523.462368] RDX: 0000000000000000 RSI: 00007fff7f05a8a0 RDI: 0000000000000003
 [  523.462369] RBP: 0000000000000000 R08: 0000000000000001 R09: 0000000000000000
 [  523.462370] R10: 0000000000000008 R11: 0000000000000246 R12: 0000000000000001
 [  523.462370] R13: 00007fff7f05ce08 R14: 0000000000000000 R15: 000055e5dfdd1040
 [  523.462373]  </TASK>
 [  523.462374] ---[ end trace ba537bc16f6bf4ed ]---

[2] https://github.com/FRRouting/frr/issues/6412

Fixes: 4c7e8084fd46 ("ipv4: Plumb support for nexthop object in a fib_info")
Signed-off-by: Nikolay Aleksandrov <razor@blackwall.org>
Reviewed-by: David Ahern <dsahern@kernel.org>
---
v2: added more information in the commit msg, no functional changes

 net/ipv4/fib_semantics.c | 7 ++++++-
 1 file changed, 6 insertions(+), 1 deletion(-)

diff --git a/net/ipv4/fib_semantics.c b/net/ipv4/fib_semantics.c
index cc8e84ef2ae4..ccb62038f6a4 100644
--- a/net/ipv4/fib_semantics.c
+++ b/net/ipv4/fib_semantics.c
@@ -889,8 +889,13 @@ int fib_nh_match(struct net *net, struct fib_config *cfg, struct fib_info *fi,
 	}
 
 	if (cfg->fc_oif || cfg->fc_gw_family) {
-		struct fib_nh *nh = fib_info_nh(fi, 0);
+		struct fib_nh *nh;
+
+		/* cannot match on nexthop object attributes */
+		if (fi->nh)
+			return 1;
 
+		nh = fib_info_nh(fi, 0);
 		if (cfg->fc_encap) {
 			if (fib_encap_match(net, cfg->fc_encap_type,
 					    cfg->fc_encap, nh, cfg, extack))
-- 
2.35.1

[PATCH net v2 2/2] selftests: net: add delete nexthop route warning test

[Nikolay Aleksandrov]

Add a test which causes a WARNING on kernels which treat a
nexthop route like a normal route when comparing for deletion and a
device is specified. That is, a route is found but we hit a warning while
matching it. The warning is from fib_info_nh() in include/net/nexthop.h
because we run it on a fib_info with nexthop object. The call chain is:
 inet_rtm_delroute -> fib_table_delete -> fib_nh_match (called with a
nexthop fib_info and also with fc_oif set thus calling fib_info_nh on
the fib_info and triggering the warning).

Repro steps:
 $ ip nexthop add id 12 via 172.16.1.3 dev veth1
 $ ip route add 172.16.101.1/32 nhid 12
 $ ip route delete 172.16.101.1/32 dev veth1

Signed-off-by: Nikolay Aleksandrov <razor@blackwall.org>
Reviewed-by: David Ahern <dsahern@kernel.org>
---
v2: adjusted test comment (dsa)

 tools/testing/selftests/net/fib_nexthops.sh | 14 ++++++++++++++
 1 file changed, 14 insertions(+)

diff --git a/tools/testing/selftests/net/fib_nexthops.sh b/tools/testing/selftests/net/fib_nexthops.sh
index d444ee6aa3cb..d8ede0c81ac1 100755
--- a/tools/testing/selftests/net/fib_nexthops.sh
+++ b/tools/testing/selftests/net/fib_nexthops.sh
@@ -1208,6 +1208,20 @@ ipv4_fcnal()
 	set +e
 	check_nexthop "dev veth1" ""
 	log_test $? 0 "Nexthops removed on admin down"
+
+	# nexthop route delete warning: route add with nhid and delete
+	# using device
+	run_cmd "$IP li set dev veth1 up"
+	run_cmd "$IP nexthop add id 12 via 172.16.1.3 dev veth1"
+	out1=`dmesg | grep "WARNING:.*fib_nh_match.*" | wc -l`
+	run_cmd "$IP route add 172.16.101.1/32 nhid 12"
+	run_cmd "$IP route delete 172.16.101.1/32 dev veth1"
+	out2=`dmesg | grep "WARNING:.*fib_nh_match.*" | wc -l`
+	[ $out1 -eq $out2 ]
+	rc=$?
+	log_test $rc 0 "Delete nexthop route warning"
+	run_cmd "$IP ip route delete 172.16.101.1/32 nhid 12"
+	run_cmd "$IP ip nexthop del id 12"
 }
 
 ipv4_grp_fcnal()
-- 
2.35.1

Re: [PATCH net v2 0/2] net: ipv4: fix nexthop route delete warning

[patchwork-bot+netdevbpf]

Hello:

This series was applied to netdev/net.git (master)
by David S. Miller <davem@davemloft.net>:

On Fri,  1 Apr 2022 10:33:41 +0300 you wrote:
> Hi,
> The first patch fixes a warning that can be triggered by deleting a
> nexthop route and specifying a device (more info in its commit msg).
> And the second patch adds a selftest for that case.
> 
> Chose this way to fix it because we should match when deleting without
> nh spec and should fail when deleting a nexthop route with old-style nh
> spec because nexthop objects are managed separately, e.g.:
> $ ip r show 1.2.3.4/32
> 1.2.3.4 nhid 12 via 192.168.11.2 dev dummy0
> 
> [...]

Here is the summary with links:
  - [net,v2,1/2] net: ipv4: fix route with nexthop object delete warning
    https://git.kernel.org/netdev/net/c/6bf92d70e690
  - [net,v2,2/2] selftests: net: add delete nexthop route warning test
    https://git.kernel.org/netdev/net/c/392baa339c6a

You are awesome, thank you!
-- 
Deet-doot-dot, I am a bot.
https://korg.docs.kernel.org/patchwork/pwbot.html

[PATCH net] selftests: net: fix nexthop warning cleanup double ip typo

[Nikolay Aleksandrov]

I made a stupid typo when adding the nexthop route warning selftest and
added both $IP and ip after it (double ip) on the cleanup path. The
error doesn't show up when running the test, but obviously it doesn't
cleanup properly after it.

Fixes: 392baa339c6a ("selftests: net: add delete nexthop route warning test")
Signed-off-by: Nikolay Aleksandrov <razor@blackwall.org>
---
The test is accurate either way.

 tools/testing/selftests/net/fib_nexthops.sh | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/tools/testing/selftests/net/fib_nexthops.sh b/tools/testing/selftests/net/fib_nexthops.sh
index d8ede0c81ac1..b3bf5319bb0e 100755
--- a/tools/testing/selftests/net/fib_nexthops.sh
+++ b/tools/testing/selftests/net/fib_nexthops.sh
@@ -1220,8 +1220,8 @@ ipv4_fcnal()
 	[ $out1 -eq $out2 ]
 	rc=$?
 	log_test $rc 0 "Delete nexthop route warning"
-	run_cmd "$IP ip route delete 172.16.101.1/32 nhid 12"
-	run_cmd "$IP ip nexthop del id 12"
+	run_cmd "$IP route delete 172.16.101.1/32 nhid 12"
+	run_cmd "$IP nexthop del id 12"
 }
 
 ipv4_grp_fcnal()
-- 
2.35.1

Re: [PATCH net] selftests: net: fix nexthop warning cleanup double ip typo

[patchwork-bot+netdevbpf]

Hello:

This patch was applied to netdev/net.git (master)
by David S. Miller <davem@davemloft.net>:

On Fri,  1 Apr 2022 18:54:27 +0300 you wrote:
> I made a stupid typo when adding the nexthop route warning selftest and
> added both $IP and ip after it (double ip) on the cleanup path. The
> error doesn't show up when running the test, but obviously it doesn't
> cleanup properly after it.
> 
> Fixes: 392baa339c6a ("selftests: net: add delete nexthop route warning test")
> Signed-off-by: Nikolay Aleksandrov <razor@blackwall.org>
> 
> [...]

Here is the summary with links:
  - [net] selftests: net: fix nexthop warning cleanup double ip typo
    https://git.kernel.org/netdev/net/c/692930cc4350

You are awesome, thank you!
-- 
Deet-doot-dot, I am a bot.
https://korg.docs.kernel.org/patchwork/pwbot.html

Re: [PATCH net v2 1/2] net: ipv4: fix route with nexthop object delete warning

[Nicolas Dichtel]

Le 01/04/2022 à 09:33, Nikolay Aleksandrov a écrit :
> FRR folks have hit a kernel warning[1] while deleting routes[2] which is
> caused by trying to delete a route pointing to a nexthop id without
> specifying nhid but matching on an interface. That is, a route is found
> but we hit a warning while matching it. The warning is from
> fib_info_nh() in include/net/nexthop.h because we run it on a fib_info
> with nexthop object. The call chain is:
>  inet_rtm_delroute -> fib_table_delete -> fib_nh_match (called with a
> nexthop fib_info and also with fc_oif set thus calling fib_info_nh on
> the fib_info and triggering the warning). The fix is to not do any
> matching in that branch if the fi has a nexthop object because those are
> managed separately. I.e. we should match when deleting without nh spec and
> should fail when deleting a nexthop route with old-style nh spec because
> nexthop objects are managed separately, e.g.:
>  $ ip r show 1.2.3.4/32
>  1.2.3.4 nhid 12 via 192.168.11.2 dev dummy0 
> 
>  $ ip r del 1.2.3.4/32
>  $ ip r del 1.2.3.4/32 nhid 12
>  <both should work>
> 
>  $ ip r del 1.2.3.4/32 dev dummy0
>  <should fail with ESRCH>
> 
> [1]
>  [  523.462226] ------------[ cut here ]------------
>  [  523.462230] WARNING: CPU: 14 PID: 22893 at include/net/nexthop.h:468 fib_nh_match+0x210/0x460
>  [  523.462236] Modules linked in: dummy rpcsec_gss_krb5 xt_socket nf_socket_ipv4 nf_socket_ipv6 ip6table_raw iptable_raw bpf_preload xt_statistic ip_set ip_vs_sh ip_vs_wrr ip_vs_rr ip_vs xt_mark nf_tables xt_nat veth nf_conntrack_netlink nfnetlink xt_addrtype br_netfilter overlay dm_crypt nfsv3 nfs fscache netfs vhost_net vhost vhost_iotlb tap tun xt_CHECKSUM xt_MASQUERADE xt_conntrack 8021q garp mrp ipt_REJECT nf_reject_ipv4 ip6table_mangle ip6table_nat iptable_mangle iptable_nat nf_nat nf_conntrack nf_defrag_ipv6 nf_defrag_ipv4 iptable_filter bridge stp llc rfcomm snd_seq_dummy snd_hrtimer rpcrdma rdma_cm iw_cm ib_cm ib_core ip6table_filter xt_comment ip6_tables vboxnetadp(OE) vboxnetflt(OE) vboxdrv(OE) qrtr bnep binfmt_misc xfs vfat fat squashfs loop nvidia_drm(POE) nvidia_modeset(POE) nvidia_uvm(POE) nvidia(POE) intel_rapl_msr intel_rapl_common snd_hda_codec_realtek snd_hda_codec_generic ledtrig_audio snd_hda_codec_hdmi btusb btrtl iwlmvm uvcvideo btbcm snd_hda_intel edac_mce_amd
>  [  523.462274]  videobuf2_vmalloc videobuf2_memops btintel snd_intel_dspcfg videobuf2_v4l2 snd_intel_sdw_acpi bluetooth snd_usb_audio snd_hda_codec mac80211 snd_usbmidi_lib joydev snd_hda_core videobuf2_common kvm_amd snd_rawmidi snd_hwdep snd_seq videodev ccp snd_seq_device libarc4 ecdh_generic mc snd_pcm kvm iwlwifi snd_timer drm_kms_helper snd cfg80211 cec soundcore irqbypass rapl wmi_bmof i2c_piix4 rfkill k10temp pcspkr acpi_cpufreq nfsd auth_rpcgss nfs_acl lockd grace sunrpc drm zram ip_tables crct10dif_pclmul crc32_pclmul crc32c_intel ghash_clmulni_intel nvme sp5100_tco r8169 nvme_core wmi ipmi_devintf ipmi_msghandler fuse
>  [  523.462300] CPU: 14 PID: 22893 Comm: ip Tainted: P           OE     5.16.18-200.fc35.x86_64 #1
>  [  523.462302] Hardware name: Micro-Star International Co., Ltd. MS-7C37/MPG X570 GAMING EDGE WIFI (MS-7C37), BIOS 1.C0 10/29/2020
>  [  523.462303] RIP: 0010:fib_nh_match+0x210/0x460
>  [  523.462304] Code: 7c 24 20 48 8b b5 90 00 00 00 e8 bb ee f4 ff 48 8b 7c 24 20 41 89 c4 e8 ee eb f4 ff 45 85 e4 0f 85 2e fe ff ff e9 4c ff ff ff <0f> 0b e9 17 ff ff ff 3c 0a 0f 85 61 fe ff ff 48 8b b5 98 00 00 00
>  [  523.462306] RSP: 0018:ffffaa53d4d87928 EFLAGS: 00010286
>  [  523.462307] RAX: 0000000000000000 RBX: ffffaa53d4d87a90 RCX: ffffaa53d4d87bb0
>  [  523.462308] RDX: ffff9e3d2ee6be80 RSI: ffffaa53d4d87a90 RDI: ffffffff920ed380
>  [  523.462309] RBP: ffff9e3d2ee6be80 R08: 0000000000000064 R09: 0000000000000000
>  [  523.462310] R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000031
>  [  523.462310] R13: 0000000000000020 R14: 0000000000000000 R15: ffff9e3d331054e0
>  [  523.462311] FS:  00007f245517c1c0(0000) GS:ffff9e492ed80000(0000) knlGS:0000000000000000
>  [  523.462313] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
>  [  523.462313] CR2: 000055e5dfdd8268 CR3: 00000003ef488000 CR4: 0000000000350ee0
>  [  523.462315] Call Trace:
>  [  523.462316]  <TASK>
>  [  523.462320]  fib_table_delete+0x1a9/0x310
>  [  523.462323]  inet_rtm_delroute+0x93/0x110
>  [  523.462325]  rtnetlink_rcv_msg+0x133/0x370
>  [  523.462327]  ? _copy_to_iter+0xb5/0x6f0
>  [  523.462330]  ? rtnl_calcit.isra.0+0x110/0x110
>  [  523.462331]  netlink_rcv_skb+0x50/0xf0
>  [  523.462334]  netlink_unicast+0x211/0x330
>  [  523.462336]  netlink_sendmsg+0x23f/0x480
>  [  523.462338]  sock_sendmsg+0x5e/0x60
>  [  523.462340]  ____sys_sendmsg+0x22c/0x270
>  [  523.462341]  ? import_iovec+0x17/0x20
>  [  523.462343]  ? sendmsg_copy_msghdr+0x59/0x90
>  [  523.462344]  ? __mod_lruvec_page_state+0x85/0x110
>  [  523.462348]  ___sys_sendmsg+0x81/0xc0
>  [  523.462350]  ? netlink_seq_start+0x70/0x70
>  [  523.462352]  ? __dentry_kill+0x13a/0x180
>  [  523.462354]  ? __fput+0xff/0x250
>  [  523.462356]  __sys_sendmsg+0x49/0x80
>  [  523.462358]  do_syscall_64+0x3b/0x90
>  [  523.462361]  entry_SYSCALL_64_after_hwframe+0x44/0xae
>  [  523.462364] RIP: 0033:0x7f24552aa337
>  [  523.462365] Code: 0e 00 f7 d8 64 89 02 48 c7 c0 ff ff ff ff eb b9 0f 1f 00 f3 0f 1e fa 64 8b 04 25 18 00 00 00 85 c0 75 10 b8 2e 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 51 c3 48 83 ec 28 89 54 24 1c 48 89 74 24 10
>  [  523.462366] RSP: 002b:00007fff7f05a838 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
>  [  523.462368] RAX: ffffffffffffffda RBX: 000000006245bf91 RCX: 00007f24552aa337
>  [  523.462368] RDX: 0000000000000000 RSI: 00007fff7f05a8a0 RDI: 0000000000000003
>  [  523.462369] RBP: 0000000000000000 R08: 0000000000000001 R09: 0000000000000000
>  [  523.462370] R10: 0000000000000008 R11: 0000000000000246 R12: 0000000000000001
>  [  523.462370] R13: 00007fff7f05ce08 R14: 0000000000000000 R15: 000055e5dfdd1040
>  [  523.462373]  </TASK>
>  [  523.462374] ---[ end trace ba537bc16f6bf4ed ]---
> 
> [2] https://github.com/FRRouting/frr/issues/6412
> 
> Fixes: 4c7e8084fd46 ("ipv4: Plumb support for nexthop object in a fib_info")
> Signed-off-by: Nikolay Aleksandrov <razor@blackwall.org>
> Reviewed-by: David Ahern <dsahern@kernel.org>
This patch has been applied in Linus' tree:
https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=6bf92d70e690

Could it be backported to stable trees?


Regards,
Nicolas

Re: [PATCH net v2 1/2] net: ipv4: fix route with nexthop object delete warning

[Jack Wang]

Nicolas Dichtel <nicolas.dichtel@6wind.com> 于2022年4月8日周五 16:47写道：
>
>
> Le 01/04/2022 à 09:33, Nikolay Aleksandrov a écrit :
> > FRR folks have hit a kernel warning[1] while deleting routes[2] which is
> > caused by trying to delete a route pointing to a nexthop id without
> > specifying nhid but matching on an interface. That is, a route is found
> > but we hit a warning while matching it. The warning is from
> > fib_info_nh() in include/net/nexthop.h because we run it on a fib_info
> > with nexthop object. The call chain is:
> >  inet_rtm_delroute -> fib_table_delete -> fib_nh_match (called with a
> > nexthop fib_info and also with fc_oif set thus calling fib_info_nh on
> > the fib_info and triggering the warning). The fix is to not do any
> > matching in that branch if the fi has a nexthop object because those are
> > managed separately. I.e. we should match when deleting without nh spec and
> > should fail when deleting a nexthop route with old-style nh spec because
> > nexthop objects are managed separately, e.g.:
> >  $ ip r show 1.2.3.4/32
> >  1.2.3.4 nhid 12 via 192.168.11.2 dev dummy0
> >
> >  $ ip r del 1.2.3.4/32
> >  $ ip r del 1.2.3.4/32 nhid 12
> >  <both should work>
> >
> >  $ ip r del 1.2.3.4/32 dev dummy0
> >  <should fail with ESRCH>
> >
> > [1]
> >  [  523.462226] ------------[ cut here ]------------
> >  [  523.462230] WARNING: CPU: 14 PID: 22893 at include/net/nexthop.h:468 fib_nh_match+0x210/0x460
> >  [  523.462236] Modules linked in: dummy rpcsec_gss_krb5 xt_socket nf_socket_ipv4 nf_socket_ipv6 ip6table_raw iptable_raw bpf_preload xt_statistic ip_set ip_vs_sh ip_vs_wrr ip_vs_rr ip_vs xt_mark nf_tables xt_nat veth nf_conntrack_netlink nfnetlink xt_addrtype br_netfilter overlay dm_crypt nfsv3 nfs fscache netfs vhost_net vhost vhost_iotlb tap tun xt_CHECKSUM xt_MASQUERADE xt_conntrack 8021q garp mrp ipt_REJECT nf_reject_ipv4 ip6table_mangle ip6table_nat iptable_mangle iptable_nat nf_nat nf_conntrack nf_defrag_ipv6 nf_defrag_ipv4 iptable_filter bridge stp llc rfcomm snd_seq_dummy snd_hrtimer rpcrdma rdma_cm iw_cm ib_cm ib_core ip6table_filter xt_comment ip6_tables vboxnetadp(OE) vboxnetflt(OE) vboxdrv(OE) qrtr bnep binfmt_misc xfs vfat fat squashfs loop nvidia_drm(POE) nvidia_modeset(POE) nvidia_uvm(POE) nvidia(POE) intel_rapl_msr intel_rapl_common snd_hda_codec_realtek snd_hda_codec_generic ledtrig_audio snd_hda_codec_hdmi btusb btrtl iwlmvm uvcvideo btbcm snd_hda_intel edac_mce_amd
> >  [  523.462274]  videobuf2_vmalloc videobuf2_memops btintel snd_intel_dspcfg videobuf2_v4l2 snd_intel_sdw_acpi bluetooth snd_usb_audio snd_hda_codec mac80211 snd_usbmidi_lib joydev snd_hda_core videobuf2_common kvm_amd snd_rawmidi snd_hwdep snd_seq videodev ccp snd_seq_device libarc4 ecdh_generic mc snd_pcm kvm iwlwifi snd_timer drm_kms_helper snd cfg80211 cec soundcore irqbypass rapl wmi_bmof i2c_piix4 rfkill k10temp pcspkr acpi_cpufreq nfsd auth_rpcgss nfs_acl lockd grace sunrpc drm zram ip_tables crct10dif_pclmul crc32_pclmul crc32c_intel ghash_clmulni_intel nvme sp5100_tco r8169 nvme_core wmi ipmi_devintf ipmi_msghandler fuse
> >  [  523.462300] CPU: 14 PID: 22893 Comm: ip Tainted: P           OE     5.16.18-200.fc35.x86_64 #1
> >  [  523.462302] Hardware name: Micro-Star International Co., Ltd. MS-7C37/MPG X570 GAMING EDGE WIFI (MS-7C37), BIOS 1.C0 10/29/2020
> >  [  523.462303] RIP: 0010:fib_nh_match+0x210/0x460
> >  [  523.462304] Code: 7c 24 20 48 8b b5 90 00 00 00 e8 bb ee f4 ff 48 8b 7c 24 20 41 89 c4 e8 ee eb f4 ff 45 85 e4 0f 85 2e fe ff ff e9 4c ff ff ff <0f> 0b e9 17 ff ff ff 3c 0a 0f 85 61 fe ff ff 48 8b b5 98 00 00 00
> >  [  523.462306] RSP: 0018:ffffaa53d4d87928 EFLAGS: 00010286
> >  [  523.462307] RAX: 0000000000000000 RBX: ffffaa53d4d87a90 RCX: ffffaa53d4d87bb0
> >  [  523.462308] RDX: ffff9e3d2ee6be80 RSI: ffffaa53d4d87a90 RDI: ffffffff920ed380
> >  [  523.462309] RBP: ffff9e3d2ee6be80 R08: 0000000000000064 R09: 0000000000000000
> >  [  523.462310] R10: 0000000000000000 R11: 0000000000000000 R12: 0000000000000031
> >  [  523.462310] R13: 0000000000000020 R14: 0000000000000000 R15: ffff9e3d331054e0
> >  [  523.462311] FS:  00007f245517c1c0(0000) GS:ffff9e492ed80000(0000) knlGS:0000000000000000
> >  [  523.462313] CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
> >  [  523.462313] CR2: 000055e5dfdd8268 CR3: 00000003ef488000 CR4: 0000000000350ee0
> >  [  523.462315] Call Trace:
> >  [  523.462316]  <TASK>
> >  [  523.462320]  fib_table_delete+0x1a9/0x310
> >  [  523.462323]  inet_rtm_delroute+0x93/0x110
> >  [  523.462325]  rtnetlink_rcv_msg+0x133/0x370
> >  [  523.462327]  ? _copy_to_iter+0xb5/0x6f0
> >  [  523.462330]  ? rtnl_calcit.isra.0+0x110/0x110
> >  [  523.462331]  netlink_rcv_skb+0x50/0xf0
> >  [  523.462334]  netlink_unicast+0x211/0x330
> >  [  523.462336]  netlink_sendmsg+0x23f/0x480
> >  [  523.462338]  sock_sendmsg+0x5e/0x60
> >  [  523.462340]  ____sys_sendmsg+0x22c/0x270
> >  [  523.462341]  ? import_iovec+0x17/0x20
> >  [  523.462343]  ? sendmsg_copy_msghdr+0x59/0x90
> >  [  523.462344]  ? __mod_lruvec_page_state+0x85/0x110
> >  [  523.462348]  ___sys_sendmsg+0x81/0xc0
> >  [  523.462350]  ? netlink_seq_start+0x70/0x70
> >  [  523.462352]  ? __dentry_kill+0x13a/0x180
> >  [  523.462354]  ? __fput+0xff/0x250
> >  [  523.462356]  __sys_sendmsg+0x49/0x80
> >  [  523.462358]  do_syscall_64+0x3b/0x90
> >  [  523.462361]  entry_SYSCALL_64_after_hwframe+0x44/0xae
> >  [  523.462364] RIP: 0033:0x7f24552aa337
> >  [  523.462365] Code: 0e 00 f7 d8 64 89 02 48 c7 c0 ff ff ff ff eb b9 0f 1f 00 f3 0f 1e fa 64 8b 04 25 18 00 00 00 85 c0 75 10 b8 2e 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 51 c3 48 83 ec 28 89 54 24 1c 48 89 74 24 10
> >  [  523.462366] RSP: 002b:00007fff7f05a838 EFLAGS: 00000246 ORIG_RAX: 000000000000002e
> >  [  523.462368] RAX: ffffffffffffffda RBX: 000000006245bf91 RCX: 00007f24552aa337
> >  [  523.462368] RDX: 0000000000000000 RSI: 00007fff7f05a8a0 RDI: 0000000000000003
> >  [  523.462369] RBP: 0000000000000000 R08: 0000000000000001 R09: 0000000000000000
> >  [  523.462370] R10: 0000000000000008 R11: 0000000000000246 R12: 0000000000000001
> >  [  523.462370] R13: 00007fff7f05ce08 R14: 0000000000000000 R15: 000055e5dfdd1040
> >  [  523.462373]  </TASK>
> >  [  523.462374] ---[ end trace ba537bc16f6bf4ed ]---
> >
> > [2] https://github.com/FRRouting/frr/issues/6412
> >
> > Fixes: 4c7e8084fd46 ("ipv4: Plumb support for nexthop object in a fib_info")
> > Signed-off-by: Nikolay Aleksandrov <razor@blackwall.org>
> > Reviewed-by: David Ahern <dsahern@kernel.org>
> This patch has been applied in Linus' tree:
> https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=6bf92d70e690
>
> Could it be backported to stable trees?

Normally stable maintainer will auto backport because the Fixes tag.
I tested with stable 5.10.y, it applied clean and the fix works.
>
>
> Regards,
> Nicolas
Regards!
Jinpu Wang @ IONOS Cloud.

Re: [PATCH net v2 1/2] net: ipv4: fix route with nexthop object delete warning

[Nicolas Dichtel]

Le 08/04/2022 à 17:06, Jack Wang a écrit :
[snip]
>> Could it be backported to stable trees?
> 
> Normally stable maintainer will auto backport because the Fixes tag.
Ok, there is no mention of this here:
https://www.kernel.org/doc/html/latest/process/stable-kernel-rules.html

Thus, I follow the 'option 2'.

> I tested with stable 5.10.y, it applied clean and the fix works.

Thanks,
Nicolas