From nobody Tue Sep 29 16:09:06 2026 X-Original-To: dev-commits-src-all@mlmmj.nyi.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1]) by mlmmj.nyi.freebsd.org (Postfix) with ESMTP id 4hvNQq3nsdz6tlxs for ; Tue, 29 Sep 2026 16:09:07 +0000 (UTC) (envelope-from git@FreeBSD.org) Received: from mxrelay.nyi.freebsd.org (mxrelay.nyi.freebsd.org [IPv6:2610:1c1:1:606c::19:3]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange x25519 server-signature RSA-PSS (4096 bits) server-digest SHA256 client-signature RSA-PSS (4096 bits) client-digest SHA256) (Client CN "mxrelay.nyi.freebsd.org", Issuer "YR2" (not verified)) by mx1.freebsd.org (Postfix) with ESMTPS id 4hvNQq0wxJz4qqX for ; Tue, 29 Sep 2026 16:09:07 +0000 (UTC) (envelope-from git@FreeBSD.org) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=freebsd.org; s=dkim; t=1790698147; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding; bh=kg9kqnwPUE+5Brvk5Yja8TfC7ZgHJOlPRyBTZtSqIDk=; b=PO9nS5XMFyOWpjn8Btps+4q/ji/UoXJDQeCY+WtxYO9MfeWbnQypr4F6IupUmXcz5zQnqa tOxwadGDzZ12+PeANfE4oPuGFh6IePlTQ7t116d78HmShQqlydIKIdVE7H9WVr7L+wHCaf N2dpSmKoeE3l6y7DPFtGFtN81dUgs2PjMCL4iB7V5oJgt2czrBW42vziJGuiDYdwT4Z3wO /yJQBPtlN6W+Z+UH2WWPmb/beWX0/t55yQ6U+P4dDRb2rjiyXh6kmKQmflDX2ZPpEO9FGq KJJTdKfb9YfF+WYfreWYLhccn6v2tX7VWz9pRJHMYV1eL0WCuP13NclxOR5HPQ== ARC-Seal: i=1; a=rsa-sha256; d=freebsd.org; s=dkim; cv=none; t=1790698147; b=pGEMMFzeieRXr7dT+v6b/WrKBcfg2mdhUV3MBA5XUiH6axo0829X6YLJrQruv1+pizVBXM EA0w18oUTdgpIDOxAmrg8/kVFfPeLBrQ+OsC/a8ttJDhJDAkYlHjiINcrSYyo7t02HM70X jKUbY+hYnvAOYH2wRSXSOd/nk0muvbVFSmqEujh5XgwiuZ6laL7Y2gIoac/iyx3MVxKOBJ sDc682FLo1fkRvTa21ftAiTm2ODgD5Ns+OQoNsF7bdaUR4P+WYI+nMiuCmbWX9j9XZlNe1 9vwlKp4Od6wmCW0ZDNe58POvLSg6a+E7VktzQTa4iz/Vq7HW5r+pd3KobwTXZA== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=freebsd.org; s=dkim; t=1790698147; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding; bh=kg9kqnwPUE+5Brvk5Yja8TfC7ZgHJOlPRyBTZtSqIDk=; b=iBZj63aYW/MN2bcPqU1aw0eB8ZOPnSUXFkB59utAvgRYGA+SwPbC/aEdK0tPJbylT0n88k ftq+NPLaUYyWNMCE7BqdR8qUvd4l0Sj7TjLHG05AI/VbH/0xWJXRqLe5DrPsV48av/ODod bki97GPs2nntkVbQUAJqu3b4WUJueNL8+i9uiBIkeNsrQlnbJFxSp7OArXmpkGhpWor48h e2QDsG3ohSuB1m7jyZFR3kUa9xB8PLs2uhTzYBlMIfrv4MvYMGbmuFgSptsmxZOFYNHEh9 GDzbk7Iszzp/QNV6z+C3qen1nJPoq2Fv/iHqqyP0cZiCz9xfl+XD4kVErwsonA== ARC-Authentication-Results: i=1; mx1.freebsd.org; none Received: from gitrepo.freebsd.org (gitrepo.freebsd.org [IPv6:2610:1c1:1:6068::e6a:5]) by mxrelay.nyi.freebsd.org (Postfix) with ESMTP id 4hvNQp748dz1KX5 for ; Tue, 29 Sep 2026 16:09:06 +0000 (UTC) (envelope-from git@FreeBSD.org) Received: from git (uid 1279) (envelope-from git@FreeBSD.org) id 30ea2 by gitrepo.freebsd.org (DragonFly Mail Agent v0.13+ on gitrepo.freebsd.org); Tue, 29 Sep 2026 16:09:06 +0000 To: src-committers@FreeBSD.org, dev-commits-src-all@FreeBSD.org, dev-commits-src-branches@FreeBSD.org From: Mark Johnston Subject: git: eb803d972fb3 - releng/14.5 - file: Add filecaps_intersect() and cap_rights_intersect() List-Id: Commit messages for all branches of the src repository List-Archive: https://lists.freebsd.org/archives/dev-commits-src-all List-Help: List-Post: List-Subscribe: List-Unsubscribe: X-BeenThere: dev-commits-src-all@freebsd.org Sender: owner-dev-commits-src-all@FreeBSD.org List-Id: List-Post: List-Help: List-Subscribe: List-Unsubscribe: List-Owner: Precedence: list MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 8bit X-Git-Committer: markj X-Git-Repository: src X-Git-Refname: refs/heads/releng/14.5 X-Git-Reftype: branch X-Git-Commit: eb803d972fb3d7c2a3af4adc631d7d2396c9aed9 Auto-Submitted: auto-generated Date: Tue, 29 Sep 2026 16:09:06 +0000 Message-Id: <6abbe2a2.30ea2.31476988@gitrepo.freebsd.org> The branch releng/14.5 has been updated by markj: URL: https://cgit.FreeBSD.org/src/commit/?id=eb803d972fb3d7c2a3af4adc631d7d2396c9aed9 commit eb803d972fb3d7c2a3af4adc631d7d2396c9aed9 Author: Mark Johnston AuthorDate: 2026-09-28 14:43:23 +0000 Commit: Mark Johnston CommitDate: 2026-09-28 18:20:13 +0000 file: Add filecaps_intersect() and cap_rights_intersect() These routines let one compute the intersection of two sets of filecaps or capability rights, just as filecaps_merge() and cap_rights_merge() compute the union. This will be useful in an upcoming patch. filecaps_intersect() is complex due to the need to merge sets of ioctls. For now this is implemented with a dumb nested loop on the basis that ioctl lists are typically short enough that this is fine. It may be better to instead sort the two lists first and step through them together. No functional change intended. Approved by: so Security: FreeBSD-SA-26:66.jail Reviewed by: kib Sponsored by: The FreeBSD Foundation Differential Revision: https://reviews.freebsd.org/D59885 --- lib/libc/capability/cap_rights_init.3 | 16 ++++++++++-- sys/kern/kern_descrip.c | 49 +++++++++++++++++++++++++++++++++++ sys/kern/subr_capability.c | 23 ++++++++++++++++ sys/sys/capsicum.h | 1 + sys/sys/filedesc.h | 1 + 5 files changed, 88 insertions(+), 2 deletions(-) diff --git a/lib/libc/capability/cap_rights_init.3 b/lib/libc/capability/cap_rights_init.3 index 98b50f653f2c..1dbb76686283 100644 --- a/lib/libc/capability/cap_rights_init.3 +++ b/lib/libc/capability/cap_rights_init.3 @@ -35,6 +35,7 @@ .Nm cap_rights_is_set , .Nm cap_rights_is_empty , .Nm cap_rights_is_valid , +.Nm cap_rights_intersect , .Nm cap_rights_merge , .Nm cap_rights_remove , .Nm cap_rights_contains @@ -56,6 +57,8 @@ .Ft bool .Fn cap_rights_is_valid "const cap_rights_t *rights" .Ft cap_rights_t * +.Fn cap_rights_intersect "cap_rights_t *dst" "const cap_rights_t *src" +.Ft cap_rights_t * .Fn cap_rights_merge "cap_rights_t *dst" "const cap_rights_t *src" .Ft cap_rights_t * .Fn cap_rights_remove "cap_rights_t *dst" "const cap_rights_t *src" @@ -133,6 +136,14 @@ function verifies if the given structure is valid. .Pp The +.Fn cap_rights_intersect +function clears all capability rights from the +.Fa dst +structure that are not present in the +.Fa src +structure, leaving only the rights common to both. +.Pp +The .Fn cap_rights_merge function merges all capability rights present in the .Fa src @@ -173,9 +184,10 @@ structure given in the argument. .Pp The -.Fn cap_rights_merge -and +.Fn cap_rights_merge , .Fn cap_rights_remove +and +.Fn cap_rights_intersect functions return pointer to the .Vt cap_rights_t structure given in the diff --git a/sys/kern/kern_descrip.c b/sys/kern/kern_descrip.c index e551944b638b..3bb10ef710f0 100644 --- a/sys/kern/kern_descrip.c +++ b/sys/kern/kern_descrip.c @@ -1854,6 +1854,55 @@ filecaps_full(const struct filecaps *fcaps) fcaps->fc_fcntls == CAP_FCNTL_ALL && fcaps->fc_nioctls == -1); } +/* + * Find the intersection of two filecaps structures and store the result in the + * first structure. This is a destructive operation on the src structure. + */ +void +filecaps_intersect(struct filecaps *src, struct filecaps *dst) +{ + + cap_rights_intersect(&dst->fc_rights, &src->fc_rights); + dst->fc_fcntls &= src->fc_fcntls; + if (dst->fc_nioctls == -1) { + dst->fc_ioctls = src->fc_ioctls; + dst->fc_nioctls = src->fc_nioctls; + src->fc_ioctls = NULL; + } else if (src->fc_nioctls != -1) { + int count; + + /* + * ioctl lists are usually short, so this dumb merge is fine. + * We could alternately sort both lists and walk them in + * parallel. + */ + count = 0; + for (int i = 0; i < dst->fc_nioctls; i++) { + bool found; + + found = false; + for (int j = 0; j < src->fc_nioctls; j++) { + if (dst->fc_ioctls[i] == src->fc_ioctls[j]) { + count++; + found = true; + break; + } + } + if (!found) { + if (i != dst->fc_nioctls - 1) + dst->fc_ioctls[i] = + dst->fc_ioctls[dst->fc_nioctls - 1]; + dst->fc_nioctls--; + i--; + } + } + dst->fc_nioctls = count; + } + if (dst->fc_nioctls == 0) + filecaps_free_ioctl(dst); + filecaps_free(src); +} + static u_long * filecaps_free_prep(struct filecaps *fcaps) { diff --git a/sys/kern/subr_capability.c b/sys/kern/subr_capability.c index 945ba9a7152d..6ed927b23367 100644 --- a/sys/kern/subr_capability.c +++ b/sys/kern/subr_capability.c @@ -312,6 +312,29 @@ cap_rights_is_valid(const cap_rights_t *rights) return (true); } +cap_rights_t * +cap_rights_intersect(cap_rights_t *dst, const cap_rights_t *src) +{ + unsigned int i, n; + + assert(CAPVER(dst) == CAP_RIGHTS_VERSION_00); + assert(CAPVER(src) == CAP_RIGHTS_VERSION_00); + assert(CAPVER(dst) == CAPVER(src)); + assert(cap_rights_is_valid(src)); + assert(cap_rights_is_valid(dst)); + + n = CAPARSIZE(dst); + assert(n >= CAPARSIZE_MIN && n <= CAPARSIZE_MAX); + + for (i = 0; i < n; i++) + dst->cr_rights[i] &= src->cr_rights[i] | ~0x01FFFFFFFFFFFFFFULL; + + assert(cap_rights_is_valid(src)); + assert(cap_rights_is_valid(dst)); + + return (dst); +} + cap_rights_t * cap_rights_merge(cap_rights_t *dst, const cap_rights_t *src) { diff --git a/sys/sys/capsicum.h b/sys/sys/capsicum.h index 255451881de1..29ed64363197 100644 --- a/sys/sys/capsicum.h +++ b/sys/sys/capsicum.h @@ -391,6 +391,7 @@ bool __cap_rights_is_set(const cap_rights_t *rights, ...); bool cap_rights_is_empty(const cap_rights_t *rights); bool cap_rights_is_valid(const cap_rights_t *rights); +cap_rights_t *cap_rights_intersect(cap_rights_t *dst, const cap_rights_t *src); cap_rights_t *cap_rights_merge(cap_rights_t *dst, const cap_rights_t *src); cap_rights_t *cap_rights_remove(cap_rights_t *dst, const cap_rights_t *src); diff --git a/sys/sys/filedesc.h b/sys/sys/filedesc.h index c6d9add81a6c..d946ce6fed34 100644 --- a/sys/sys/filedesc.h +++ b/sys/sys/filedesc.h @@ -245,6 +245,7 @@ bool filecaps_copy(const struct filecaps *src, struct filecaps *dst, void filecaps_move(struct filecaps *src, struct filecaps *dst); void filecaps_free(struct filecaps *fcaps); bool filecaps_full(const struct filecaps *fcaps); +void filecaps_intersect(struct filecaps *src, struct filecaps *dst); int closef(struct file *fp, struct thread *td); void closef_nothread(struct file *fp);