From nobody Tue Sep 29 15:57:32 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 4hvN9T1LFTz6tlJM for ; Tue, 29 Sep 2026 15:57:33 +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 4hvN9T0PHGz4YVl for ; Tue, 29 Sep 2026 15:57:33 +0000 (UTC) (envelope-from git@FreeBSD.org) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=freebsd.org; s=dkim; t=1790697453; 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=eSa9AGhVWJtVgyGEKvsWRBMANtf+SyeN9xO8ZDKRWIw=; b=iEhk6QYT6/jsmTwtvJlh+lPFCFDdXJAns+hCqEHJ5AlBFGp+bB+rF75et28eLEZGjM7x+p mx0UKG3MO5WoDjgED3wOQ44XZclsBOMSA01MS2yKSW/+uk7yxevwDeLhfPZcOuNP59cn3h 1VDuepBwrKK1fwwqy5Re/m/m2HZZuGAKiYjThNUCvBtwP2ND41VZCixmjmipUAj3pOpsTe isxZ4UFFskoML+aFfjouT/HsbWj8Na8jMFBsHdZBIjctJEjlfTVaIq/NNGlI3VX8lXfSv6 s6tcmhbt0oZ16FTW/Eskj2e4TRbCG4hSFu2Ms+soz69yf1r87ox552q9rZCAwA== ARC-Seal: i=1; a=rsa-sha256; d=freebsd.org; s=dkim; cv=none; t=1790697453; b=t1lfEVbUnFJk+c7L8PKQ5vosVu8izu5uepu7JW/PLrCoHLVsPdY3xnyVUYyos8OGk9xwqj TJFon2Mdliqq87T2VqJBc5EfYQTYkf/XMksxYr9Ufle9l3OMvMvp4B8allXRn+QQBpt1ql 83h1KInElN5KapedTCWN84i2sL35cwZQnGc2o/VeRuD1mYpRE+hqnm4KGN3yBXuXn4z4Fz vjWv3CpIG/DRgOrR1cmUYzM3lC3ZQhEaSgfhWPnBb6EXS+IGfsiFds7IqFQI2iZy40AFar 2L5DAW8dzr1lQ8wAGvfNqqCvCQ778YruE4k7uyMc4S/jrnqohugyWVg9h8pT8g== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=freebsd.org; s=dkim; t=1790697453; 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=eSa9AGhVWJtVgyGEKvsWRBMANtf+SyeN9xO8ZDKRWIw=; b=BbuXGO40qwrY0LhK3wcVgZWxw213oU21g54iW9aT7RcyyWh3PzkSwyRiFdGIdN8bxO8cUu N9D9CZQ5WmHA4lN/pEqYyFPkLwXO2Z7fPjM13SXuS+ioZvjA3cPEaRQwqg0DBgs650IYKt za28gnjna6kZXH5ffkv+PrBeufdoyhQd4Yn+Qq8z7eT9ha2laeSeV+1XhX6dOYDKzTLi7o Sc+dnfxqW5CShzhyNoYUl/oCQ0oUM4voHN+sfRhru2wlkc/eKueE/zODyj8xId0Q6KYMlW IEus6R+vYJNIOmpg21A+Idl6I590+bASN0RhdPfqvP429EwJapy6HbyjCapnow== 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 4hvN9S0F04z1KRk for ; Tue, 29 Sep 2026 15:57:32 +0000 (UTC) (envelope-from git@FreeBSD.org) Received: from git (uid 1279) (envelope-from git@FreeBSD.org) id 24a59 by gitrepo.freebsd.org (DragonFly Mail Agent v0.13+ on gitrepo.freebsd.org); Tue, 29 Sep 2026 15:57:32 +0000 To: src-committers@FreeBSD.org, dev-commits-src-all@FreeBSD.org, dev-commits-src-branches@FreeBSD.org From: Mark Johnston Subject: git: 790bfee896a7 - releng/14.4 - 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/14.4 X-Git-Reftype: branch X-Git-Commit: 790bfee896a733ce9dc60f743c0872885b529d81 Auto-Submitted: auto-generated Date: Tue, 29 Sep 2026 15:57:32 +0000 Message-Id: <6abbdfec.24a59.425df6e@gitrepo.freebsd.org> The branch releng/14.4 has been updated by markj: URL: https://cgit.FreeBSD.org/src/commit/?id=790bfee896a733ce9dc60f743c0872885b529d81 commit 790bfee896a733ce9dc60f743c0872885b529d81 Author: Mark Johnston AuthorDate: 2026-09-28 14:43:23 +0000 Commit: Mark Johnston CommitDate: 2026-09-28 17:53:19 +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 19d038fec651..8f09a6ed0fa3 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 b4fedb402b43..e13d908b20fe 100644 --- a/sys/kern/subr_capability.c +++ b/sys/kern/subr_capability.c @@ -308,6 +308,29 @@ 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 9dd34cff943a..b739bf1782bb 100644 --- a/sys/sys/capsicum.h +++ b/sys/sys/capsicum.h @@ -340,6 +340,7 @@ 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 48c90823343a..d9ed02b13fb8 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);