From nobody Tue Oct 29 18:45:33 2024 X-Original-To: dev-commits-src-branches@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 4XdK2P62gMz5bmwL; Tue, 29 Oct 2024 18:45:33 +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 "R10" (verified OK)) by mx1.freebsd.org (Postfix) with ESMTPS id 4XdK2P3hWTz41MT; Tue, 29 Oct 2024 18:45:33 +0000 (UTC) (envelope-from git@FreeBSD.org) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=freebsd.org; s=dkim; t=1730227533; 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=yFsF2+OC2rVu22NbAPE8RshtD/C4COSH/VfHflYh2h8=; b=SK0xtrocGpPeUyRbU468tORcEnAHSmG9WPkjBVfTOER5hD6/IEgVBzOI7WDImk1wULpN8s hJPY1ldP58XLd4xFyn2h+46jSjKlwTiD60WReX9Tv83htTTnY0GAbdDGfmVLziY79Wk3lG 2dFaLn17bJ3x7ApvAwTXuna78tBISRuigRAAGEREI3hzI7CMGkOiaN1aq7WiSonuUs+YbB gp+0rKQZLMzbInBap0NSP2PlSqJob+NoTD8bz1BozweSCL4DI/Iqb6fDa1dH3Q3wxsz5av 8Lnp10A6NEqpe3iajr3OU5JQ4iCOs0cRJS71xr6VWY/Q4P/EkcCr+2qvUAR68w== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=freebsd.org; s=dkim; t=1730227533; 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=yFsF2+OC2rVu22NbAPE8RshtD/C4COSH/VfHflYh2h8=; b=X9ntaD4o3aMMroL3Z3H4v5RzKqeRcA1B2IIu6Py2KlGuoCfzOLW5zUu/8NAEfB5uIhjdWM mvAp/A0GuQYrVltllTGagBP3323VLZbSlpDgtxWis1/ZaeWVfXmGIBDuPEv6xciyO81AIF cQnARorF3b8GfPeJ4o/TIhSz4knHg5PMX3kZc7q38OTQ9GX621LZrfg8ipwdpLPdpr0o7o rol91C+Cz/GzPBt169EPyKnAn/zmYu/kLOqKm0g2VikRn/Y4lTGpWO9sCV0Ly/+AraioRu /IYQYN6d8HlZF7FzcjcYCF0Lj9K3SF6dkW7mha6T6qcRsd+zWlv12H/QQ9K8aQ== ARC-Authentication-Results: i=1; mx1.freebsd.org; none ARC-Seal: i=1; s=dkim; d=freebsd.org; t=1730227533; a=rsa-sha256; cv=none; b=BsJhF6jtT5+j7gN9h27/iJ8XMEgA07K5nw9rTwqhcaPFJ3o6JcO+VOgc5G2xTBsbcTsSWT CRaw4ASgP/VB7hUfXvekG6WNqi3LckaJnPkRvGoC3481jTzSdn2Gb133Vkyrd5GIHPv2YI 8QcZoScwlekQar+pFIDDEIbtg+ocvTxvMJta8iQQ4BERDHBJK0TI79mN0iJtFI4ueRIPLD nlIQyERyvhmQVSQhJHWVyhNtj+UCHke5K796Yzjm555sI8H1pP8iT/R013CeF7M7Az07Eb YWWU8eLAHpZUnEk5pJMamo76xe2hMndbM3she9uh0NV0jSBHD991Coq/yvOhjw== Received: from gitrepo.freebsd.org (gitrepo.freebsd.org [IPv6:2610:1c1:1:6068::e6a:5]) (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 did not present a certificate) by mxrelay.nyi.freebsd.org (Postfix) with ESMTPS id 4XdK2P3Hblzbd2; Tue, 29 Oct 2024 18:45:33 +0000 (UTC) (envelope-from git@FreeBSD.org) Received: from gitrepo.freebsd.org ([127.0.1.44]) by gitrepo.freebsd.org (8.18.1/8.18.1) with ESMTP id 49TIjXZR016917; Tue, 29 Oct 2024 18:45:33 GMT (envelope-from git@gitrepo.freebsd.org) Received: (from git@localhost) by gitrepo.freebsd.org (8.18.1/8.18.1/Submit) id 49TIjXxd016914; Tue, 29 Oct 2024 18:45:33 GMT (envelope-from git) Date: Tue, 29 Oct 2024 18:45:33 GMT Message-Id: <202410291845.49TIjXxd016914@gitrepo.freebsd.org> To: src-committers@FreeBSD.org, dev-commits-src-all@FreeBSD.org, dev-commits-src-branches@FreeBSD.org From: Ed Maste Subject: git: 9b11b889402a - releng/14.1 - bhyve: avoid TOCTOU on iov_len in virtio_vq_recordon() List-Id: Commits to the stable branches of the FreeBSD src repository List-Archive: https://lists.freebsd.org/archives/dev-commits-src-branches List-Help: List-Post: List-Subscribe: List-Unsubscribe: X-BeenThere: dev-commits-src-branches@freebsd.org Sender: owner-dev-commits-src-branches@FreeBSD.org MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 8bit X-Git-Committer: emaste X-Git-Repository: src X-Git-Refname: refs/heads/releng/14.1 X-Git-Reftype: branch X-Git-Commit: 9b11b889402aa3f85545464f4ead5da537638a12 Auto-Submitted: auto-generated The branch releng/14.1 has been updated by emaste: URL: https://cgit.FreeBSD.org/src/commit/?id=9b11b889402aa3f85545464f4ead5da537638a12 commit 9b11b889402aa3f85545464f4ead5da537638a12 Author: Pierre Pronchery AuthorDate: 2024-08-27 13:57:32 +0000 Commit: Ed Maste CommitDate: 2024-10-29 18:43:16 +0000 bhyve: avoid TOCTOU on iov_len in virtio_vq_recordon() Avoid a race condition when accessing guest memory, by reading memory contents only once. This has also been applied to _vq_record() in sys/dev/beri/virtio/virtio.c, as per markj@'s suggestion. Reported by: Synacktiv Reviewed by: markj Security: HYP-10 Security: FreeBSD-SA-24:17.bhyve Approved by: so Sponsored by: The Alpha-Omega Project Sponsored by: The FreeBSD Foundation Differential Revision: https://reviews.freebsd.org/D45735 (cherry picked from commit 869d760cb9d7a307faa2fbe8c1c2b238a81b74d4) (cherry picked from commit ed03c309908687bdb9f71dc6d9c9c8a92c54fc20) --- sys/dev/beri/virtio/virtio.c | 11 ++++++++--- usr.sbin/bhyve/virtio.c | 9 +++++++-- 2 files changed, 15 insertions(+), 5 deletions(-) diff --git a/sys/dev/beri/virtio/virtio.c b/sys/dev/beri/virtio/virtio.c index c249d1c9d37b..7302bc39d799 100644 --- a/sys/dev/beri/virtio/virtio.c +++ b/sys/dev/beri/virtio/virtio.c @@ -107,12 +107,17 @@ paddr_unmap(void *phys, uint32_t size) static inline void _vq_record(uint32_t offs, int i, volatile struct vring_desc *vd, struct iovec *iov, int n_iov, uint16_t *flags) { + uint32_t len; + uint64_t addr; + if (i >= n_iov) return; - iov[i].iov_base = paddr_map(offs, be64toh(vd->addr), - be32toh(vd->len)); - iov[i].iov_len = be32toh(vd->len); + len = atomic_load_32(&vd->len); + addr = atomic_load_64(&vd->addr); + iov[i].iov_base = paddr_map(offs, be64toh(addr), + be32toh(len)); + iov[i].iov_len = be32toh(len); if (flags != NULL) flags[i] = be16toh(vd->flags); } diff --git a/usr.sbin/bhyve/virtio.c b/usr.sbin/bhyve/virtio.c index 0aeafa011bbc..5e8f8a8d322a 100644 --- a/usr.sbin/bhyve/virtio.c +++ b/usr.sbin/bhyve/virtio.c @@ -217,10 +217,15 @@ static inline void _vq_record(int i, struct vring_desc *vd, struct vmctx *ctx, struct iovec *iov, int n_iov, struct vi_req *reqp) { + uint32_t len; + uint64_t addr; + if (i >= n_iov) return; - iov[i].iov_base = paddr_guest2host(ctx, vd->addr, vd->len); - iov[i].iov_len = vd->len; + len = atomic_load_32(&vd->len); + addr = atomic_load_64(&vd->addr); + iov[i].iov_len = len; + iov[i].iov_base = paddr_guest2host(ctx, addr, len); if ((vd->flags & VRING_DESC_F_WRITE) == 0) reqp->readable++; else