Re: Fwd: [Bug 69841] New: "double free or corruption" with mod_socache_dbm (socache_dbm_retrieve() + database_cleanup())

Joe Orton <[email protected]> Tue, 7 Oct 2025 10:50:44 +0100

Newsgroups	gmane.comp.apache.devel
Organization	Registered in England and Wales under Company Registration No. 03798903 Directors: Michael Cunningham (US), Michael O'Neill (Ireland), Paul Argiry (US)
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On Tue, Oct 07, 2025 at 10:45:27AM +0100, Joe Orton wrote:
> There should already be a global lock held by API consumer, since the 
> socache provider is marked with AP_SOCACHE_FLAG_NOTMPSAFE. It looks like 
> mod_authn_socache is protecting entry to the socache provider inside a 
> global mutex without checking that flag - overkill but should be safe.

Ah, not true, it only does it for ->store(). The ->retrieve() calls are 
then unsafe and racy, that's definitely a bug.