tree 4e4c86657b5a16a592d015ceef7e20b092cd4f46
parent fc85494c9917a6b5029053056509d3b5cc6e5def
author Christopher Faulet <cfaulet@haproxy.com> 1599660584 +0200
committer Christopher Faulet <cfaulet@haproxy.com> 1599810874 +0200

BUG/MEDIUM: pattern: Renew the pattern expression revision when it is pruned

It must be done to expire patterns cached in the LRU cache. Otherwise it is
possible to retrieve an already freed pattern, attached to a released pattern
expression.

When a specific pattern is deleted (->delete() callback), the pattern expression
revision is already renewed. Thus it is not affected by this bug. Only prune
action on the pattern expression is concerned.

In addition, for a pattern expression, in ->prune() callbacks when the pattern
list is released, a missing LIST_DEL() has been added. It is not a real issue
because the list is reinitialized at the end and all elements are released and
should never be reused. But it is less confusing this way.

This bug may be triggered when a map is cleared from the cli socket. A
workaround is to set the pattern cache size (tune.pattern.cache-size) to 0 to
disable it.

This patch should fix the issue #844. It must be backported to all supported
versions.