Fix error deleting TCPMSS clamp rule in route agent #3187
Merged
Conversation
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
|
🤖 Created branch: z_pr3187/tpantelis/iptables_mss_clamp |
aswinsuryan
approved these changes
Oct 17, 2024
vthapar
approved these changes
Oct 17, 2024
This warning was observed on route agent restart:
2024-10-15T18:30:34.752Z WRN ..etfilter/adapter.go:120 Packetfilter
Unable to delete rule "packetfilter.Rule{Action: MSS,
SrcCIDR: 172.31.0.0/16}" from table "Filter", chain
"SUBMARINER-FWD-MSSCLAMP": error deleting rule "-s 172.31.0.0/16
-j TCPMSS" from table "filter", chain "SUBMARINER-FWD-MSSCLAMP":
running [/usr/sbin/iptables -t filter -D SUBMARINER-FWD-MSSCLAMP
-s 172.31.0.0/16 -j TCPMSS --wait 5]: exit status 2: iptables
v1.8.8 (nf_tables): TCPMSS target:
At least one parameter is required
Try `iptables -h' or 'iptables --help' for more information.
The problem is that we're not specifying either "--clamp-mss-to-pmtu"
or "--set-mss" after "-j TCPMSS". This is due to incorrect parsing
of the rule string returned from the iptables command. We're
expecting "-p tcp -m tcp --tcp-flags SYN,RST SYN" to be right after
"-j TCPMSS" the same as we write it out when appeneding but iptables
returns the parameters in a different order with "--clamp-mss-to-pmtu"
or "--set-mss" right after "-j TCPMSS", eg
"-p tcp -m tcp --tcp-flags SYN,RST SYN -j TCPMSS --set-mss 1500"
So we miss parsing the TCPMSS parameter and thus don't set the
MssClampType field correctly.
Modify the parsing to handle the parameters in any order.
Signed-off-by: Tom Pantelis <tompantelis@gmail.com>
35b7676 to
63aa202
Compare
|
🤖 Closed branches: [z_pr3187/tpantelis/iptables_mss_clamp] |
aswinsuryan
added a commit
to tpantelis/submariner
that referenced
this pull request
Oct 17, 2024
…3187-upstream-release-0.19
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
Add this suggestion to a batch that can be applied as a single commit.
This suggestion is invalid because no changes were made to the code.
Suggestions cannot be applied while the pull request is closed.
Suggestions cannot be applied while viewing a subset of changes.
Only one suggestion per line can be applied in a batch.
Add this suggestion to a batch that can be applied as a single commit.
Applying suggestions on deleted lines is not supported.
You must change the existing code in this line in order to create a valid suggestion.
Outdated suggestions cannot be applied.
This suggestion has been applied or marked resolved.
Suggestions cannot be applied from pending reviews.
Suggestions cannot be applied on multi-line comments.
Suggestions cannot be applied while the pull request is queued to merge.
Suggestion cannot be applied right now. Please check back later.
This warning was observed on route agent restart:
The problem is that we're not specifying either
--clamp-mss-to-pmtuor--set-mssafter-j TCPMSS. This is due to incorrect parsing of the rule string returned from the iptables command. We're expecting-p tcp -m tcp --tcp-flags SYN,RST SYNto be right after-j TCPMSSthe same as we write it out when appending but iptables returns the parameters in a different order with--clamp-mss-to-pmtuor--set-mssright after-j TCPMSS, eg-p tcp -m tcp --tcp-flags SYN,RST SYN -j TCPMSS --set-mss 1500So we miss parsing the TCPMSS parameter and thus don't set the
MssClampTypefield correctly.Modify the parsing to handle the parameters in any order.