From nobody Tue Sep 29 15:59:15 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 4hvNCR3gsmz6tlV3 for ; Tue, 29 Sep 2026 15:59:15 +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 4hvNCR12hbz4dp5 for ; Tue, 29 Sep 2026 15:59:15 +0000 (UTC) (envelope-from git@FreeBSD.org) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=freebsd.org; s=dkim; t=1790697555; 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=tGmV0OrWmoS7NIK+uszU1UhpeuIP51MdHaYn8Gy64X8=; b=W2UxoxR+tE3fn6XXyJ7aCqZzHWVRwO6ztrB2GkzLYpwrZLYJY+a11xbgNZzlASkYiUCF5k dzRELLaviAHzlKx+Hlubt1OaAAEoWALcTtqoAnwwwbHayKWRtj8AMn15u5QwtSkJyNXzy3 umB+VWyQBaGBUvGUEGB9zoW2HJ+J2K4JnGUD3LAJ7PZWfVzBQpfer8itQwX78QJOEUf9Ej zSxvpV4ez/1SVycViKuJP67UVX0EzPJnrSmKeZ/Fl0dvHwQ9gDKN9Z0jGhQfNIoO+yhab3 PLo3sdW3bn07HVQwchD5qYzPbPQN/wfA2RXyL5pDFYvF4YazkuTvum/SKjDaQA== ARC-Seal: i=1; a=rsa-sha256; d=freebsd.org; s=dkim; cv=none; t=1790697555; b=fqTKydOGV6mWadxcJf3Yrd7YGbqNTmd//+D1zc3MnXawDlKnuhv+48/1SAnUFf6h3/cVLX kmWfZoyPknZdiA93lziRzRlatUm3ClwLdC1fshq062uHoOzLpApx3YrdcxHkUNLK4FPmgX 2EVIzdbl5s8+BY/a5g8EizJzsd9SqbR2yqSUSgu1Gaj2p6UFdZoyz9YCeVuJNZMnUPFpeZ 3omh1azdn7H0hgFIJYLOBmbxvREBWKEEtIP7wL3WB8pxFICCbGkRuqXP8u0D+WZFyZmbo4 dgYexenw83pgkKa3PlEl0tEN0nyn6XdNuoBWv3SFuEQe607TSRSyCGoWm7LMTg== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=freebsd.org; s=dkim; t=1790697555; 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=tGmV0OrWmoS7NIK+uszU1UhpeuIP51MdHaYn8Gy64X8=; b=AU0x47qPf67V3vOgS6/AurRcU+KiiiRLWGqvqvikkEx26yqFC6tkGb2a3fdex40OPYQab8 bgROsWY2eiSvkpqIQ6aDArLC36VM6SdiPsrGxnvXt3n/fXLEpeOLbpxyelUfkU3bTadxdl FCzlG6uVF3cDYL7oPnjHT24looo93+Srs3PiTdJDFEAauUL3fMq4iR3WbFjQfP4J4Kp+IH 2BI3U+cz+LzM9CIKpukZaAGhMsXL0O7N4MkpZvPZc7KSy59XsW6BlLSKj+zm1snD2AsMu1 QitS+QaklrxjMdqkbIjuJUL/a7g/OjPDbXrsNTkFq+7l1hkpuSMDl2U9TTpNbA== 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 4hvNCR06p7z1KPc for ; Tue, 29 Sep 2026 15:59:15 +0000 (UTC) (envelope-from git@FreeBSD.org) Received: from git (uid 1279) (envelope-from git@FreeBSD.org) id 26be9 by gitrepo.freebsd.org (DragonFly Mail Agent v0.13+ on gitrepo.freebsd.org); Tue, 29 Sep 2026 15:59:15 +0000 To: src-committers@FreeBSD.org, dev-commits-src-all@FreeBSD.org, dev-commits-src-branches@FreeBSD.org From: Mark Johnston Subject: git: 440547e0fcfd - releng/15.0 - 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/15.0 X-Git-Reftype: branch X-Git-Commit: 440547e0fcfd4865d98931e3fb327ddc8a40e38a Auto-Submitted: auto-generated Date: Tue, 29 Sep 2026 15:59:15 +0000 Message-Id: <6abbe053.26be9.18098120@gitrepo.freebsd.org> The branch releng/15.0 has been updated by markj: URL: https://cgit.FreeBSD.org/src/commit/?id=440547e0fcfd4865d98931e3fb327ddc8a40e38a commit 440547e0fcfd4865d98931e3fb327ddc8a40e38a Author: Mark Johnston AuthorDate: 2026-09-28 14:43:23 +0000 Commit: Mark Johnston CommitDate: 2026-09-28 18:14:40 +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 2dfe7b445099..e9eeea59e4be 100644 --- a/sys/kern/kern_descrip.c +++ b/sys/kern/kern_descrip.c @@ -1940,6 +1940,55 @@ 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 5ad5b0af1681..e0cec63bba06 100644 --- a/sys/kern/subr_capability.c +++ b/sys/kern/subr_capability.c @@ -313,6 +313,29 @@ 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 3847c4c73e75..a6811e2de9b6 100644 --- a/sys/sys/capsicum.h +++ b/sys/sys/capsicum.h @@ -344,6 +344,7 @@ 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 eea96350e6e1..b34b50ca78ae 100644 --- a/sys/sys/filedesc.h +++ b/sys/sys/filedesc.h @@ -243,6 +243,7 @@ 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);