[libvirt] [PATCH] qemu: hotplug: Don't access srcPriv when it's not allocated

[Marc Hartmayer]

On Tue, Jul 03, 2018 at 04:22 PM +0200, Peter Krempa <pkrempa at redhat.com> wrote:
> On Tue, Jul 03, 2018 at 09:34:56 -0400, John Ferlan wrote:
>>
>>
>> On 07/03/2018 08:05 AM, Peter Krempa wrote:
>> > The private data of a virStorageSource which is backing an iSCSI hostdev
>> > may be NULL if no authentication is present. The code handling the
>> > hotplug would attempt to extract the authentication info stored in
>> > 'secinfo' without checking if it is allocated which resulted in a crash.
>> >
>> > Here we opt the easy way to check if srcPriv is not NULL so that we
>> > don't duplicate all the logic which selects whether the disk source has
>> > a secret.
>> >
>> > Resolves: https://bugzilla.redhat.com/show_bug.cgi?id=1597550
>> >
>> > Signed-off-by: Peter Krempa <pkrempa at redhat.com>
>> > ---
>> >  src/qemu/qemu_hotplug.c | 3 ++-
>> >  1 file changed, 2 insertions(+), 1 deletion(-)
>> >
>>
>> Reviewed-by: John Ferlan <jferlan at redhat.com>
>>
>> John
>>
>> Feels like we've done this before...
>>
>> 97202988 <sigh> and 6050affb7f
>
> Specifically the former commit was not good enough to cover this case
> despite touching this code.

Would it make sense to always allocate the
qemuDomainStorageSourcePrivate struct? We’d be wasting some memory, but
at the same time the code would be easier to read and less prone to
error. e.g. qemuDomainDeviceDiskDefPostParseRestoreSecAlias would be
simpler.

For the privateData of virConnect, virDomainVsockDef, virDisk,
virDomainVcpu… it’s implemented this way.

Anyway: Reviewed-by: Marc Hartmayer <mhartmay at linux.ibm.com> and thanks
for fixing it!

>
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Beste Grüße / Kind regards
   Marc Hartmayer

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