From: Andreas Dilger Subject: Re: [PATCH 7/7] libext2fs: enforce the block group descriptor size in ext2fs_open() Date: Tue, 31 Jul 2012 11:38:47 -0700 Message-ID: References: <20120628024356.GB17989@thor.bakeyournoodle.com> <1343684862-13181-1-git-send-email-tytso@mit.edu> <1343684862-13181-7-git-send-email-tytso@mit.edu> Mime-Version: 1.0 (1.0) Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 8BIT Cc: Ext4 Developers List , "tony@bakeyournoodle.com" , Theodore Ts'o To: Theodore Ts'o Return-path: Received: from mail-gh0-f174.google.com ([209.85.160.174]:34560 "EHLO mail-gh0-f174.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752368Ab2GaSkk convert rfc822-to-8bit (ORCPT ); Tue, 31 Jul 2012 14:40:40 -0400 Received: by ghrr11 with SMTP id r11so6386325ghr.19 for ; Tue, 31 Jul 2012 11:40:39 -0700 (PDT) In-Reply-To: <1343684862-13181-7-git-send-email-tytso@mit.edu> Sender: linux-ext4-owner@vger.kernel.org List-ID: On 2012-07-30, at 14:47, Theodore Ts'o wrote: > Since various parts of the library depend on the value of s_desc_size, > check to make sure it is the correct, expected value based on the file > system features. > > Signed-off-by: "Theodore Ts'o" > --- > lib/ext2fs/ext2_err.et.in | 3 +++ > lib/ext2fs/openfs.c | 15 +++++++++++++++ > 2 files changed, 18 insertions(+) > > diff --git a/lib/ext2fs/ext2_err.et.in b/lib/ext2fs/ext2_err.et.in > index ccf1894..5987185 100644 > --- a/lib/ext2fs/ext2_err.et.in > +++ b/lib/ext2fs/ext2_err.et.in > @@ -443,4 +443,7 @@ ec EXT2_ET_MMP_CHANGE_ABORT, > ec EXT2_ET_MMP_OPEN_DIRECT, > "MMP: open with O_DIRECT failed" > > +ec EXT2_ET_BAD_DESC_SIZE, > + "Block group descriptor size incorrect" > + > end > diff --git a/lib/ext2fs/openfs.c b/lib/ext2fs/openfs.c > index 482e4ab..fbe9acd 100644 > --- a/lib/ext2fs/openfs.c > +++ b/lib/ext2fs/openfs.c > @@ -263,6 +263,21 @@ errcode_t ext2fs_open2(const char *name, const char *io_options, > retval = EXT2_ET_CORRUPT_SUPERBLOCK; > goto cleanup; > } > + > + /* Enforce the block group descriptor size */ > + if (fs->super->s_feature_incompat & EXT4_FEATURE_INCOMPAT_64BIT) { > + if (fs->super->s_desc_size != EXT2_MIN_DESC_SIZE_64BIT) { It doesn't necessarily make sense to limit this to the minimum size, only that it is at least the minimum size. Cheers, Andreas > + retval = EXT2_ET_BAD_DESC_SIZE; > + goto cleanup; > + } > + } else { > + if (fs->super->s_desc_size && > + fs->super->s_desc_size != EXT2_MIN_DESC_SIZE) { > + retval = EXT2_ET_BAD_DESC_SIZE; > + goto cleanup; > + } > + } > + > fs->cluster_ratio_bits = fs->super->s_log_cluster_size - > fs->super->s_log_block_size; > if (EXT2_BLOCKS_PER_GROUP(fs->super) != > -- > 1.7.12.rc0.22.gcdd159b > > -- > To unsubscribe from this list: send the line "unsubscribe linux-ext4" in > the body of a message to majordomo@vger.kernel.org > More majordomo info at http://vger.kernel.org/majordomo-info.html