From mboxrd@z Thu Jan 1 00:00:00 1970 Received: from smtp.kernel.org (aws-us-west-2-korg-mail-1.web.codeaurora.org [10.30.226.201]) (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 2404F28E1 for ; Sun, 3 Dec 2023 19:09:51 +0000 (UTC) Authentication-Results: smtp.subspace.kernel.org; dkim=pass (2048-bit key) header.d=kernel.org header.i=@kernel.org header.b="KKLlsXKZ" Received: by smtp.kernel.org (Postfix) with ESMTPSA id 91F68C433C7; Sun, 3 Dec 2023 19:09:51 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1701630591; bh=EgqN46+GaUk00ZRhhxLX+mSBvbfugLiSZ9aQqe6sboM=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=KKLlsXKZRusHvQRq1WXh+ty3rDc/THJ9RhxNPwTr09ZGw1o98kUee7isuccTZn92o No3cog1mmk2mE6J+hd9YSGndui9sOWU9UthCO5S0e1pstiP3kR7X7zBq9B8rGkDWED vlqCFSxkbg1FJjiZ9T++ogp8EpQzUTmEs8Bgy3uweetivQgAoGgpZtkyX99fJNV7xp e8NIkDMe9r5ChkA4qSWh8lAQOgl4XlR+YUTBGtWe06U5AZ+pmAwaD41Kl2mkaopt93 6eKe+JYwVqcFv5ccmwY50lUTIUaHvNgqPChwY3Eno75StPvHMoDVBAVj8sgeSLQZX8 MAPzJSQ2kZVAQ== Date: Sun, 3 Dec 2023 11:09:51 -0800 From: "Darrick J. Wong" To: chandanbabu@kernel.org, hch@lst.de Cc: linux-xfs@vger.kernel.org Subject: Re: [PATCH 3/3] xfs: don't allow overly small or large realtime volumes Message-ID: <20231203190951.GV361584@frogsfrogsfrogs> References: <170162990622.3038044.5313475096294285406.stgit@frogsfrogsfrogs> <170162990673.3038044.6698602496725473343.stgit@frogsfrogsfrogs> Precedence: bulk X-Mailing-List: linux-xfs@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: <170162990673.3038044.6698602496725473343.stgit@frogsfrogsfrogs> On Sun, Dec 03, 2023 at 11:05:50AM -0800, Darrick J. Wong wrote: > From: Darrick J. Wong > > Don't allow realtime volumes that are less than one rt extent long. > This has been broken across 4 LTS kernels with nobody noticing, so let's > just disable it. > > Per the previous patch, I also observed integer overflows in calculating > rextslog (the number of rt summary levels) when the rtextent count > exceeds 2^32. If you're lucky, this means that mkfs will fail to format > the filesystem; if not, then the fs will go down due to corruption > errors. Prohibit those too; larger volume support will return with > rtgroups. ....aaand I forgot to update the commit message on this one, sorry. Strike the previous paragraph, please. --D > Signed-off-by: Darrick J. Wong > --- > fs/xfs/libxfs/xfs_rtbitmap.h | 12 ++++++++++++ > fs/xfs/libxfs/xfs_sb.c | 3 ++- > fs/xfs/xfs_rtalloc.c | 2 ++ > 3 files changed, 16 insertions(+), 1 deletion(-) > > > diff --git a/fs/xfs/libxfs/xfs_rtbitmap.h b/fs/xfs/libxfs/xfs_rtbitmap.h > index 1610d0e4a04c..411de3b889ae 100644 > --- a/fs/xfs/libxfs/xfs_rtbitmap.h > +++ b/fs/xfs/libxfs/xfs_rtbitmap.h > @@ -353,6 +353,18 @@ int xfs_rtfree_blocks(struct xfs_trans *tp, xfs_fsblock_t rtbno, > > uint8_t xfs_compute_rextslog(xfs_rtbxlen_t rtextents); > > +/* Do we support an rt volume having this number of rtextents? */ > +static inline bool > +xfs_validate_rtextents( > + xfs_rtbxlen_t rtextents) > +{ > + /* No runt rt volumes */ > + if (rtextents == 0) > + return false; > + > + return true; > +} > + > xfs_filblks_t xfs_rtbitmap_blockcount(struct xfs_mount *mp, xfs_rtbxlen_t > rtextents); > unsigned long long xfs_rtbitmap_wordcount(struct xfs_mount *mp, > diff --git a/fs/xfs/libxfs/xfs_sb.c b/fs/xfs/libxfs/xfs_sb.c > index df12bf82ed18..4a9e8588f4c9 100644 > --- a/fs/xfs/libxfs/xfs_sb.c > +++ b/fs/xfs/libxfs/xfs_sb.c > @@ -509,7 +509,8 @@ xfs_validate_sb_common( > rbmblocks = howmany_64(sbp->sb_rextents, > NBBY * sbp->sb_blocksize); > > - if (sbp->sb_rextents != rexts || > + if (!xfs_validate_rtextents(rexts) || > + sbp->sb_rextents != rexts || > sbp->sb_rextslog != xfs_compute_rextslog(rexts) || > sbp->sb_rbmblocks != rbmblocks) { > xfs_notice(mp, > diff --git a/fs/xfs/xfs_rtalloc.c b/fs/xfs/xfs_rtalloc.c > index 7c5a50163d2d..8feb58c6241c 100644 > --- a/fs/xfs/xfs_rtalloc.c > +++ b/fs/xfs/xfs_rtalloc.c > @@ -963,6 +963,8 @@ xfs_growfs_rt( > */ > nrextents = nrblocks; > do_div(nrextents, in->extsize); > + if (!xfs_validate_rtextents(nrextents)) > + return -EINVAL; > nrbmblocks = xfs_rtbitmap_blockcount(mp, nrextents); > nrextslog = xfs_compute_rextslog(nrextents); > nrsumlevels = nrextslog + 1; > >