Bug 1721330 - ip route list infinite loop if 255.255.255.255 route exists
Summary: ip route list infinite loop if 255.255.255.255 route exists
Keywords:
Status: CLOSED CURRENTRELEASE
Alias: None
Product: Fedora
Classification: Fedora
Component: kernel
Version: rawhide
Hardware: Unspecified
OS: Unspecified
unspecified
unspecified
Target Milestone: ---
Assignee: Kernel Maintainer List
QA Contact: Fedora Extras Quality Assurance
URL:
Whiteboard:
Depends On:
Blocks:
TreeView+ depends on / blocked
 
Reported: 2019-06-17 23:42 UTC by Jeffrey C. Ollie
Modified: 2022-09-15 10:48 UTC (History)
21 users (show)

Fixed In Version:
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Clone Of:
Environment:
Last Closed: 2022-09-15 10:48:19 UTC
Type: Bug
Embargoed:


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Description Jeffrey C. Ollie 2019-06-17 23:42:24 UTC
Description of problem:
"ip route list" loops endlessly if there's a 255.255.255.255 route in the routing table.

Version-Release number of selected component (if applicable):
iproute-5.1.0-1.fc30.aarch64

How reproducible:
Easily

Steps to Reproduce:
1. ip route add 255.255.255.255 dev wlan0
2. ip route list

Actual results:

# ip route list
default via 192.168.4.1 dev eth0 proto dhcp src 192.168.4.58 metric 1024 
10.42.42.0/24 dev wlan0 proto kernel scope link src 10.42.42.1 
192.168.4.0/24 dev eth0 proto kernel scope link src 192.168.4.58 
192.168.4.1 dev eth0 proto dhcp scope link src 192.168.4.58 metric 1024 
255.255.255.255 dev wlan0 scope link 
default via 192.168.4.1 dev eth0 proto dhcp src 192.168.4.58 metric 1024 
10.42.42.0/24 dev wlan0 proto kernel scope link src 10.42.42.1 
192.168.4.0/24 dev eth0 proto kernel scope link src 192.168.4.58 
192.168.4.1 dev eth0 proto dhcp scope link src 192.168.4.58 metric 1024 
255.255.255.255 dev wlan0 scope link 
default via 192.168.4.1 dev eth0 proto dhcp src 192.168.4.58 metric 1024 
10.42.42.0/24 dev wlan0 proto kernel scope link src 10.42.42.1 
192.168.4.0/24 dev eth0 proto kernel scope link src 192.168.4.58 
192.168.4.1 dev eth0 proto dhcp scope link src 192.168.4.58 metric 1024 
255.255.255.255 dev wlan0 scope link 

and on and on and on until you kill the process or remove the route

Expected results:

# ip route list
default via 192.168.4.1 dev eth0 proto dhcp src 192.168.4.58 metric 1024 
10.42.42.0/24 dev wlan0 proto kernel scope link src 10.42.42.1 
192.168.4.0/24 dev eth0 proto kernel scope link src 192.168.4.58 
192.168.4.1 dev eth0 proto dhcp scope link src 192.168.4.58 metric 1024 
255.255.255.255 dev wlan0 scope link 
#


Additional info:

Comment 1 Phil Sutter 2019-06-19 11:15:07 UTC
Problem originates in kernel space, RHEL7 is fine with current upstream iproute2. Current net-next kernel has the problem as well.

Comment 2 Justin M. Forbes 2019-08-20 17:43:42 UTC
*********** MASS BUG UPDATE **************

We apologize for the inconvenience.  There are a large number of bugs to go through and several of them have gone stale.  Due to this, we are doing a mass bug update across all of the Fedora 30 kernel bugs.

Fedora 30 has now been rebased to 5.2.9-200.fc30.  Please test this kernel update (or newer) and let us know if you issue has been resolved or if it is still present with the newer kernel.

If you have moved on to Fedora 31, and are still experiencing this issue, please change the version to Fedora 31.

If you experience different issues, please open a new bug report for those.

Comment 3 Justin M. Forbes 2019-09-17 20:14:41 UTC
*********** MASS BUG UPDATE **************
This bug is being closed with INSUFFICIENT_DATA as there has not been a response in 3 weeks. If you are still experiencing this issue, please reopen and attach the relevant data from the latest kernel you are running and any data that might have been requested previously.

Comment 4 Phil Sutter 2019-09-19 17:07:33 UTC
Issue is still relevant.

Comment 5 Phil Sutter 2022-09-15 10:48:19 UTC
This issue should be fixed by following kernel commit:

9827c0634e461 ("ipv4: Detect rollover in specific fib table dump")

it is mainline since v5.5 and therefore present in F30 onwards.


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