[libvirt] Memory leak in libvirt / gnutls
I'm trying to track down:
https://bugzilla.redhat.com/show_bug.cgi?id=810613
I *think* this is a libvirt bug, but I can only reproduce it on one
machine, not on another machine that has a virtually identical setup.
Anyway, something is confusing me about libvirt. In this commit:
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commit 74c75671331d284e1f777f9692b72e9737520bf0
Author: Michal Privoznik <mprivozn(a)redhat.com>
Date: Thu Aug 18 10:44:08 2011 +0200
daemon: initialize GnuTLS
When spice_tls is set but listen_tls is not, we don't initialize
GnuTLS library. So any later gnutls call (e.g. during migration,
where we initialize a certificate) will access uninitialized GnuTLS
internal structs and throws an error.
Although, we might now initialize GnuTLS twice, it is safe according
to the documentation:
This function can be called many times,
but will only do something the first time.
This patch creates 2 functions: virNetTLSInit and virNetTLSDeinit
with respect to written above.
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... a pair of functions called virNetTLSInit & virNetTLSDeinit are
introduced, which would appear to do the right thing, calling first
gnutls_global_init, then gnutls_global_deinit. This looks correct to
me.
However the above commit is later amended by this commit:
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commit eaddec976ef06457fee4a4ce86b8c7ee906183b7
Author: Michal Privoznik <mprivozn(a)redhat.com>
Date: Wed Aug 24 16:16:45 2011 +0200
daemon: Move TLS initialization to virInitialize
My previous patch 74c75671331d284e1f777f9692b72e9737520bf0
introduced a regression by removing TLS initialization from client.
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which removes virNetTLSDeinit. This appears to be a mistake, or at
least I can't see the logical reason for it, and according to the
gnutls docs, it would introduce a memory leak looking exactly like the
one I am chasing down.
The current code mentions virNetTLSDeinit only in a comment, and never
calls gnutls_global_deinit.
Any ideas?
Rich.
--
Richard Jones, Virtualization Group, Red Hat http://people.redhat.com/~rjones
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