Opened 6 years ago

Closed 6 years ago

#10314 closed defect (wontfix)

/dev/random unavailable on WZR-HP-AG300H

Reported by: Bogdan <abr28@…> Owned by: developers
Priority: normal Milestone: Backfire 10.03.1
Component: kernel Version: Trunk
Keywords: Cc:


This is an issue I've seen reported for other devices (even fixed for some apparently). On my Buffalo WZR-HP-AG300H running trunk r28428 /dev/random just doesn't have enough entropy, even after days of uptime:

random: Cannot read from /dev/random: Resource temporarily unavailable
random: Only 0/20 bytes of strong random data available from /dev/random
random: Not enough entropy pool available for secure operations
WPA: Not enough entropy in random pool for secure operations - update keys later when the first station connects

10h since the above message:

root@OpenWrt:~# cat /proc/sys/kernel/random/entropy_avail

Sure I can hack /dev/random to use /dev/urandom or use rng-tools but /dev/random should just work ... there are random sources available and quite active, e.g. wired nic.

Attachments (0)

Change History (3)

comment:1 Changed 6 years ago by hnyman

there are random sources available and quite active, e.g. wired nic.

Based on your text, you probably have seen the ticket #9631 which concerns this ar71xx devices problem. I mentioned there a few links to discussions on the general Linux development forums, where the Linux developers seem to have actively decided to remove network drivers as entropy sources, as they feared that an attacker might send carefully timed packages to the NIC. That sounds overcautious, but probably we won't see network drivers coming back as entropy sources. That is a real problem for the headless systems like routers (as there is no user input related randomness).

Hopefully the devs can figure out some way to get randomness into ar71xx devices.

comment:2 Changed 6 years ago by rechapita@…

This entrophy issue is also affecting dir-600-b1 (RT305x)

comment:3 Changed 6 years ago by nbd

  • Resolution set to wontfix
  • Status changed from new to closed

it'll force entropy availability after the first connection attempt (and create a stamp file so that it works even after wifi restart).

Add Comment

Modify Ticket

as closed .
The resolution will be deleted. Next status will be 'reopened'.

E-mail address and user name can be saved in the Preferences.

Note: See TracTickets for help on using tickets.