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Bug #237

Bug #235: meta: Missing list checks for *list_add*

batadv_neigh_node_new: Missing list checks for *list_add*

Added by Sven Eckelmann over 5 years ago. Updated about 1 year ago.

Status:
Closed
Priority:
Normal
Assignee:
Target version:
Start date:
06/26/2015
Due date:
% Done:

100%

Estimated time:

Description

Simon debugged the refcnt problem and submitted some patches to fix them. I had a brief look and noticed that there are possible more problems similar to the *list_del* ones - just with *list_add*. Basically some functions use some kind of get function, notice that the element does not exist and then create a new one to add to the list. Only the "list_add" is protected. The result may be that an element in twice in a list when only a single occurrence is allowed.

The problem I saw is that functions adding objects in an RCU protected list are missing an definitive check. They first call some kind of *_get (rcu_read_lock only) to check if an object with this value already exists and then uses some kind of *_add to allocate a new object and add it (which may already be added in by a different context). So it has to be made sure that nothing modifies the list between the check and the add of the new object).

Linus already proposed a patch: https://patchwork.open-mesh.org/project/b.a.t.m.a.n./patch/1452150672-11174-2-git-send-email-linus.luessing@c0d3.blue/


Related issues

Related to batman-adv - Bug #242: batadv_neigh_node_release: Double batadv_hardif_neigh_putClosed03/05/2016

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History

#1

Updated by Sven Eckelmann over 5 years ago

  • Related to Bug #242: batadv_neigh_node_release: Double batadv_hardif_neigh_put added
#2

Updated by Sven Eckelmann about 5 years ago

  • % Done changed from 0 to 100
  • Status changed from New to Resolved

Looks like Linus' patch was accepted.

#3

Updated by Sven Eckelmann about 5 years ago

  • Status changed from Resolved to Closed
#4

Updated by Sven Eckelmann over 4 years ago

  • Target version set to 2016.2
#5

Updated by Sven Eckelmann about 1 year ago

  • Description updated (diff)

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