varlink: ensure that userdata is always valid#18171
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topimiettinen wants to merge 1 commit intosystemd:masterfrom
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varlink: ensure that userdata is always valid#18171topimiettinen wants to merge 1 commit intosystemd:masterfrom
topimiettinen wants to merge 1 commit intosystemd:masterfrom
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structured initialization in C sets unmentioned fields to zero implicitly, hence you patch changes exactly nothing. We typically only initialize the fields that shall not be zero when using structured initialization. |
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The fix could also/instead include one or more of the below
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Hmm. Could this be a bug in the compiler? |
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How about this: varlink_server_add_connection() invoked by connect_callback() sets the Varlink->userdata from VarlinkServer->userdata. In case of resolved, it expects Varlink->userdata to be a DnsQuery but VarlinkServer->userdata is a Manager. So perhaps the fix could be to change varlink_server_add_connection() to use NULL instead. |
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Actually, just remove this line. |
In case the callers use struct Varlink field `userdata` without first setting it, it will contain a non-NULL pointer but possibly pointing to wrong data, so let's keep the NULL from varlink_new() instead of initializing it from VarlinkServer->userdata.
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Let's scratch this, it doesn't work. |
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a48481d removed zero initialization of struct Varlink in
varlink_new(). However, the callers may (wrongly) use field
userdatawithoutfirst setting it, so let's set it to NULL.