Date: Fri, 4 Dec 2020 02:19:46 +0000 (UTC) From: Kyle Evans <kevans@FreeBSD.org> To: src-committers@freebsd.org, svn-src-all@freebsd.org, svn-src-stable@freebsd.org, svn-src-stable-12@freebsd.org Subject: svn commit: r368322 - stable/12/sys/kern Message-ID: <202012040219.0B42JkPX055042@repo.freebsd.org>
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Author: kevans Date: Fri Dec 4 02:19:45 2020 New Revision: 368322 URL: https://svnweb.freebsd.org/changeset/base/368322 Log: MFC r367944: cpuset_setproc: use the appropriate parent for new anon. sets As far as I can tell, this has been the case since initially committed in 2008. cpuset_setproc is the executor of cpuset reassignment; note this excerpt from the description: * 1) Set is non-null. This reparents all anonymous sets to the provided * set and replaces all non-anonymous td_cpusets with the provided set. However, reviewing cpuset_setproc_setthread() for some jail related work unearthed the error: if tdset was not anonymous, we were replacing it with `set`. If it was anonymous, then we'd rebase it onto `set` (i.e. copy the thread's mask over and AND it with `set`) but give the new anonymous set the original tdset as the parent (i.e. the base of the set we're supposed to be leaving behind). The primary visible consequences were that: 1.) cpuset_getid() following such assignment returns the wrong result, the setid that we left behind rather than the one we joined. 2.) When a process attached to the jail, the base set of any anonymous threads was a set outside of the jail. This was initially bundled in D27298, but it's a minor fix that's fairly easy to verify the correctness of. A test is included in D27307 ("badparent"), which demonstrates the issue with, effectively: osetid = cpuset_getid() newsetid = cpuset() cpuset_setaffinity(thread) cpuset_setid(osetid) cpuset_getid(thread) -> observe that it matches newsetid instead of osetid. Modified: stable/12/sys/kern/kern_cpuset.c Directory Properties: stable/12/ (props changed) Modified: stable/12/sys/kern/kern_cpuset.c ============================================================================== --- stable/12/sys/kern/kern_cpuset.c Fri Dec 4 02:18:40 2020 (r368321) +++ stable/12/sys/kern/kern_cpuset.c Fri Dec 4 02:19:45 2020 (r368322) @@ -1095,7 +1095,7 @@ cpuset_setproc_setthread(struct cpuset *tdset, struct if (error) return (error); - return cpuset_shadow(tdset, nsetp, &mask, &domain, freelist, + return cpuset_shadow(set, nsetp, &mask, &domain, freelist, domainlist); }
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