Date: Sun, 31 Dec 2017 05:16:23 +0000 (UTC) From: Mateusz Guzik <mjg@FreeBSD.org> To: src-committers@freebsd.org, svn-src-all@freebsd.org, svn-src-stable@freebsd.org, svn-src-stable-11@freebsd.org Subject: svn commit: r327415 - stable/11/sys/kern Message-ID: <201712310516.vBV5GN7F042066@repo.freebsd.org>
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Author: mjg Date: Sun Dec 31 05:16:23 2017 New Revision: 327415 URL: https://svnweb.freebsd.org/changeset/base/327415 Log: MFC r324045: sysctl: remove target buffer read/write checks prior to calling the handler Said checks were inherently racy anyway as jokers could unmap target areas before the handler got around to accessing them. This saves time by avoiding locking the address space. Modified: stable/11/sys/kern/kern_sysctl.c Directory Properties: stable/11/ (props changed) Modified: stable/11/sys/kern/kern_sysctl.c ============================================================================== --- stable/11/sys/kern/kern_sysctl.c Sun Dec 31 05:14:40 2017 (r327414) +++ stable/11/sys/kern/kern_sysctl.c Sun Dec 31 05:16:23 2017 (r327415) @@ -1982,16 +1982,9 @@ userland_sysctl(struct thread *td, int *name, u_int na } } req.validlen = req.oldlen; + req.oldptr = old; - if (old) { - if (!useracc(old, req.oldlen, VM_PROT_WRITE)) - return (EFAULT); - req.oldptr= old; - } - if (new != NULL) { - if (!useracc(new, newlen, VM_PROT_READ)) - return (EFAULT); req.newlen = newlen; req.newptr = new; }
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