From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.129.124]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.subspace.kernel.org (Postfix) with ESMTPS id 6FFE835C694 for ; Tue, 21 Jul 2026 22:24:17 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; arc=none smtp.client-ip=170.10.129.124 ARC-Seal:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1784672658; cv=none; b=PDkClmBb8an4Vo685KIjG7033jXchdqxTwen5BH20QzO9ghOihq3r3v2USkQtlC56qOPOVJvr3uICm4SdB8PMTaVLXKAHPtSJ/aVHeTlpU8FwRbkVo+AdvOkDCQQWAbh3tznxVEjGL44yOX8w3cHSwfDeGHwCiP8QmD0aPVlsBI= ARC-Message-Signature:i=1; a=rsa-sha256; d=subspace.kernel.org; s=arc-20240116; t=1784672658; c=relaxed/simple; bh=mFicWt8aljInn2brndV6GeUi5W3rCzOm8ugvkdiJ0FQ=; h=Date:From:To:Cc:Subject:Message-ID:References:MIME-Version: Content-Type:Content-Disposition:In-Reply-To; b=KMTizMDm9kcdmo5HjKHZHginYMPVncVIk/vJ40exO80b0Dtnc/o5ksmF+hWlKZq2vhmQcbmQ37ertMX3t0rnYu9XMjOHBuoSbEG0LNUYpJ0h2x47SLBbNqgUixnphIQLYyQB6S6Lez980rKfzYrZtotSEpEU9iM+PRenmypvy/A= ARC-Authentication-Results:i=1; smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=redhat.com; spf=pass smtp.mailfrom=redhat.com; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b=fqY1gz8W; arc=none smtp.client-ip=170.10.129.124 Authentication-Results: smtp.subspace.kernel.org; dmarc=pass (p=quarantine dis=none) header.from=redhat.com Authentication-Results: smtp.subspace.kernel.org; spf=pass smtp.mailfrom=redhat.com Authentication-Results: smtp.subspace.kernel.org; dkim=pass (1024-bit key) header.d=redhat.com header.i=@redhat.com header.b="fqY1gz8W" DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1784672656; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: in-reply-to:in-reply-to:references:references; bh=oPXEp+EfITlWhZAB6Di0vMxuPC1WvdgC2PfXnEXo3Bs=; b=fqY1gz8WmPvfiZVv1VgAQGK5je8eiPPRSuq7dxXdQT18SsFvDBtNyEvI1lfyKqfvK0Hi1+ YzL/GULlopz16AR+KaeroeZcQKJ0TtJmALeaeYZsvd1dhULFKnpnp1xG47QlFWkvmVx3i5 DpCGj5WqXVLO4PIkplfZu+YTx8twTTw= Received: from mx-prod-mc-01.mail-002.prod.us-west-2.aws.redhat.com (ec2-54-186-198-63.us-west-2.compute.amazonaws.com [54.186.198.63]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_256_GCM_SHA384) id us-mta-252-W1GBf-SfOSuXR1PCiT9nHw-1; Tue, 21 Jul 2026 18:17:58 -0400 X-MC-Unique: W1GBf-SfOSuXR1PCiT9nHw-1 X-Mimecast-MFC-AGG-ID: W1GBf-SfOSuXR1PCiT9nHw_1784672276 Received: from mx-prod-int-06.mail-002.prod.us-west-2.aws.redhat.com (mx-prod-int-06.mail-002.prod.us-west-2.aws.redhat.com [10.30.177.93]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by mx-prod-mc-01.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id 38D80195FD25; Tue, 21 Jul 2026 22:17:56 +0000 (UTC) Received: from madcap2.tricolour.ca (unknown [10.22.58.2]) by mx-prod-int-06.mail-002.prod.us-west-2.aws.redhat.com (Postfix) with ESMTPS id CF90118008F7; Tue, 21 Jul 2026 22:17:53 +0000 (UTC) Date: Tue, 21 Jul 2026 18:17:51 -0400 From: Richard Guy Briggs To: Ricardo Robaina Cc: audit@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org, paul@paul-moore.com, eparis@redhat.com, viro@zeniv.linux.org.uk, brauner@kernel.org, jack@suse.cz, sgrubb@redhat.com Subject: Re: [PATCH] audit: add MOVE_MOUNT auxiliary record to log mount relocation Message-ID: References: <20260713170035.4073532-1-rrobaina@redhat.com> Precedence: bulk X-Mailing-List: linux-kernel@vger.kernel.org List-Id: List-Subscribe: List-Unsubscribe: MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20260713170035.4073532-1-rrobaina@redhat.com> X-Scanned-By: MIMEDefang 3.4.1 on 10.30.177.93 On 2026-07-13 14:00, Ricardo Robaina wrote: > Modern mount tools (util-linux >= 2.39.1) use the new mount API > (fsopen, fsconfig, fsmount, move_mount) instead of the legacy mount(2) > syscall. The generic SYSCALL audit record logs the move_mount syscall > but does not capture the flags argument, creating an audit gap for > mount relocation operations. > > Add a MOVE_MOUNT auxiliary record that logs the flags argument passed > to move_mount(2). Pathnames and file descriptors are captured through > existing PATH records and SYSCALL record arguments. > > ---- > type=PATH : item=0 name=/mnt/test_src inode=1 dev=00:41 ... > type=SYSCALL : arch=x86_64 syscall=move_mount ... > type=MOVE_MOUNT : fs_flags=0x4 > ---- > type=PATH : item=0 name=/mnt/test_dst inode=27460862 dev=fc:00 ... > type=SYSCALL : arch=x86_64 syscall=move_mount ... > type=MOVE_MOUNT : fs_flags=0x4 > > Link: https://github.com/linux-audit/audit-kernel/issues/152 > Link: https://github.com/linux-audit/audit-kernel/issues/153 > Signed-off-by: Ricardo Robaina Reviewed-by: Richard Guy Briggs > --- > fs/namespace.c | 3 +++ > include/linux/audit.h | 10 ++++++++++ > include/uapi/linux/audit.h | 1 + > kernel/auditsc.c | 13 +++++++++++++ > 4 files changed, 27 insertions(+) > > diff --git a/fs/namespace.c b/fs/namespace.c > index 3d5cd5bf3b05..a6b0286744d9 100644 > --- a/fs/namespace.c > +++ b/fs/namespace.c > @@ -34,6 +34,7 @@ > #include > #include > #include > +#include > > #include "pnode.h" > #include "internal.h" > @@ -4625,6 +4626,8 @@ SYSCALL_DEFINE5(move_mount, > if (flags & MOVE_MOUNT_F_EMPTY_PATH) > uflags = AT_EMPTY_PATH; > > + audit_log_move_mount(flags); > + > CLASS(filename_maybe_null,from_name)(from_pathname, uflags); > if (!from_name && from_dfd >= 0) { > CLASS(fd_raw, f_from)(from_dfd); > diff --git a/include/linux/audit.h b/include/linux/audit.h > index 45abb3722d30..d1dc4035cb3c 100644 > --- a/include/linux/audit.h > +++ b/include/linux/audit.h > @@ -449,6 +449,7 @@ extern void __audit_tk_injoffset(struct timespec64 offset); > extern void __audit_ntp_log(const struct audit_ntp_data *ad); > extern void __audit_log_nfcfg(const char *name, u8 af, unsigned int nentries, > enum audit_nfcfgop op, gfp_t gfp); > +extern void __audit_log_move_mount(unsigned int flags); > > static inline void audit_ipc_obj(struct kern_ipc_perm *ipcp) > { > @@ -598,6 +599,12 @@ static inline void audit_log_nfcfg(const char *name, u8 af, > __audit_log_nfcfg(name, af, nentries, op, gfp); > } > > +static inline void audit_log_move_mount(unsigned int flags) > +{ > + if (!audit_dummy_context()) > + __audit_log_move_mount(flags); > +} > + > extern int audit_n_rules; > extern int audit_signals; > #else /* CONFIG_AUDITSYSCALL */ > @@ -730,6 +737,9 @@ static inline void audit_log_nfcfg(const char *name, u8 af, > enum audit_nfcfgop op, gfp_t gfp) > { } > > +static inline void audit_log_move_mount(unsigned int flags) > +{ } > + > #define audit_n_rules 0 > #define audit_signals 0 > #endif /* CONFIG_AUDITSYSCALL */ > diff --git a/include/uapi/linux/audit.h b/include/uapi/linux/audit.h > index e8f5ce677df7..40abf3dfd307 100644 > --- a/include/uapi/linux/audit.h > +++ b/include/uapi/linux/audit.h > @@ -122,6 +122,7 @@ > #define AUDIT_OPENAT2 1337 /* Record showing openat2 how args */ > #define AUDIT_DM_CTRL 1338 /* Device Mapper target control */ > #define AUDIT_DM_EVENT 1339 /* Device Mapper events */ > +#define AUDIT_MOVE_MOUNT 1342 /* Record showing move_mount flags */ > > #define AUDIT_AVC 1400 /* SE Linux avc denial or grant */ > #define AUDIT_SELINUX_ERR 1401 /* Internal SE Linux Errors */ > diff --git a/kernel/auditsc.c b/kernel/auditsc.c > index 6610e667c728..4aca04d33d00 100644 > --- a/kernel/auditsc.c > +++ b/kernel/auditsc.c > @@ -2882,6 +2882,19 @@ void __audit_log_nfcfg(const char *name, u8 af, unsigned int nentries, > } > EXPORT_SYMBOL_GPL(__audit_log_nfcfg); > > +void __audit_log_move_mount(unsigned int flags) > +{ > + struct audit_buffer *ab; > + > + ab = audit_log_start(audit_context(), GFP_KERNEL, > + AUDIT_MOVE_MOUNT); > + if (!ab) > + return; > + > + audit_log_format(ab, "fs_flags=0x%x", flags); > + audit_log_end(ab); > +} > + > static void audit_log_task(struct audit_buffer *ab) > { > kuid_t auid, uid; > -- > 2.53.0 - RGB -- Richard Guy Briggs Sr. S/W Engineer, Kernel Security, Base Operating Systems Remote, Ottawa, Red Hat Canada Upstream IRC: SunRaycer Voice: +1.613.860 2354 SMS: +1.613.518.6570