Date: Mon, 24 May 2021 15:41:03 GMT From: Kristof Provost <kp@FreeBSD.org> To: src-committers@FreeBSD.org, dev-commits-src-all@FreeBSD.org, dev-commits-src-branches@FreeBSD.org Subject: git: b34127064fde - stable/12 - pf: Set the pfik_group for userspace Message-ID: <202105241541.14OFf3dt023934@gitrepo.freebsd.org>
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The branch stable/12 has been updated by kp: URL: https://cgit.FreeBSD.org/src/commit/?id=b34127064fde4d144b6d63dce0eada01563bc562 commit b34127064fde4d144b6d63dce0eada01563bc562 Author: Kristof Provost <kp@FreeBSD.org> AuthorDate: 2021-05-16 06:50:17 +0000 Commit: Kristof Provost <kp@FreeBSD.org> CommitDate: 2021-05-24 15:40:28 +0000 pf: Set the pfik_group for userspace Userspace relies on this pointer to work out if the kif is a group or not. It can't use it for anything else, because it's a pointer to a kernel address. Substitute 0xfeedc0de for 'true', so that we don't leak kernel memory addresses to userspace. PR: 255852 Reviewed by: donner MFC after: 1 week Differential Revision: https://reviews.freebsd.org/D30284 (cherry picked from commit d69cc040147284c414dfd1c9f498dcc7c8291a8b) --- sys/netpfil/pf/pf_if.c | 8 ++++++++ 1 file changed, 8 insertions(+) diff --git a/sys/netpfil/pf/pf_if.c b/sys/netpfil/pf/pf_if.c index 656cdfab6018..9c10be3b3b77 100644 --- a/sys/netpfil/pf/pf_if.c +++ b/sys/netpfil/pf/pf_if.c @@ -817,6 +817,14 @@ pf_kkif_to_kif(const struct pfi_kkif *kkif, struct pfi_kif *kif) kif->pfik_flags = kkif->pfik_flags; kif->pfik_tzero = kkif->pfik_tzero; kif->pfik_rulerefs = kkif->pfik_rulerefs; + /* + * Userspace relies on this pointer to decide if this is a group or + * not. We don't want to share the actual pointer, because it's + * useless to userspace and leaks kernel memory layout information. + * So instead we provide 0xfeedcode as 'true' and NULL as 'false'. + */ + kif->pfik_group = + kkif->pfik_group ? (struct ifg_group *)0xfeedc0de : NULL; } void
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