From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755739Ab3K2Vyu (ORCPT ); Fri, 29 Nov 2013 16:54:50 -0500 Received: from mailbigip.dreamhost.com ([208.97.132.5]:58428 "EHLO homiemail-a12.g.dreamhost.com" rhost-flags-OK-OK-OK-FAIL) by vger.kernel.org with ESMTP id S1754024Ab3K2Vys (ORCPT ); Fri, 29 Nov 2013 16:54:48 -0500 Message-ID: <1385762083.20396.48.camel@chiang> Subject: Re: [PATCH v6] e2fsck: Correct ext4 dates generated by old kernels. From: David Turner To: Mark Harris Cc: Andreas Dilger , "Theodore Ts'o" , Jan Kara , Ext4 Developers List , Linux Kernel Mailing List Date: Fri, 29 Nov 2013 16:54:43 -0500 In-Reply-To: <1384463193.1957.27.camel@chiang> References: <1383808590.23882.13.camel@chiang> <20131107160341.GA3850@quack.suse.cz> <1383864864.23882.33.camel@chiang> <20131107231445.GG2054@quack.suse.cz> <1383866807.23882.41.camel@chiang> <1383981551.8994.27.camel@chiang> <1384070214.8994.47.camel@chiang> <20131112003018.GA30281@thunk.org> <6DE0AF86-98E6-4DE9-BB7F-40FB32E1BC26@dilger.ca> <1384326020.8994.186.camel@chiang> <276FA06E-1EE0-4FB4-94E1-B6D9F05F0B5B@dilger.ca> <1384418641.1957.1.camel@chiang> <1384463193.1957.27.camel@chiang> Content-Type: text/plain; charset="UTF-8" X-Mailer: Evolution 3.6.4-0ubuntu1 Mime-Version: 1.0 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Is this version good, or should I make some more improvements? On Thu, 2013-11-14 at 16:06 -0500, David Turner wrote: > Not sure what the official subject line format is for revising only > one of N patches, so I'm trying this one. Let me now if it is wrong. > > On Thu, 2013-11-14 at 02:15 -0800, Mark Harris wrote: > > > + * mis-encoded. > > > + */ > > > +#define EXT4_EXTRA_NEGATIVE_DATE_CUTOFF 5 * (1ULL << 32) > > > > Wouldn't 2242 be 0x200000000ULL, i.e. 2 * (1ULL << 32)? > > Actually, it would be 2 * (1LL << 32), because we later use it in a > comparison with a signed value. > > -- > Older kernels on 64-bit machines would incorrectly encode pre-1970 > ext4 dates as post-2311 dates. Detect and correct this (assuming the > current date is before 2242). > > Signed-off-by: David Turner > --- > e2fsck/pass1.c | 41 +++++++++++++++++++++++++++++++++++++++++ > e2fsck/problem.c | 4 ++++ > e2fsck/problem.h | 4 ++++ > 3 files changed, 49 insertions(+) > > diff --git a/e2fsck/pass1.c b/e2fsck/pass1.c > index ab23e42..e19855f 100644 > --- a/e2fsck/pass1.c > +++ b/e2fsck/pass1.c > @@ -348,6 +348,24 @@ fix: > EXT2_INODE_SIZE(sb), "pass1"); > } > > +#define EXT4_EPOCH_BITS 2 > +#define EXT4_EPOCH_MASK ((1 << EXT4_EPOCH_BITS) - 1) > + > +static int check_inode_extra_negative_epoch(__u32 xtime, __u32 extra) { > + return (xtime & (1 << 31)) != 0 && > + (extra & EXT4_EPOCH_MASK) == EXT4_EPOCH_MASK; > +} > + > +#define CHECK_INODE_EXTRA_NEGATIVE_EPOCH(inode, xtime) \ > + check_inode_extra_negative_epoch(inode->i_##xtime, \ > + inode->i_##xtime##_extra) > + > +/* When today's date is earlier than 2242, we assume that atimes, > + * ctimes, and mtimes with years in the range 2310..2378 are actually > + * pre-1970 dates mis-encoded. > + */ > +#define EXT4_EXTRA_NEGATIVE_DATE_CUTOFF 2 * (1LL << 32) > + > static void check_inode_extra_space(e2fsck_t ctx, struct problem_context *pctx) > { > struct ext2_super_block *sb = ctx->fs->super; > @@ -388,6 +406,29 @@ static void check_inode_extra_space(e2fsck_t ctx, struct problem_context *pctx) > /* it seems inode has an extended attribute(s) in body */ > check_ea_in_inode(ctx, pctx); > } > + > + /* > + * If the inode's extended atime (ctime, mtime) is stored in > + * the old, invalid format, repair it. > + */ > + if (sizeof(time_t) > 4 && ctx->now < EXT4_EXTRA_NEGATIVE_DATE_CUTOFF && > + (CHECK_INODE_EXTRA_NEGATIVE_EPOCH(inode, atime) || > + CHECK_INODE_EXTRA_NEGATIVE_EPOCH(inode, ctime) || > + CHECK_INODE_EXTRA_NEGATIVE_EPOCH(inode, mtime))) { > + > + if (!fix_problem(ctx, PR_1_EA_TIME_OUT_OF_RANGE, pctx)) > + return; > + > + if (CHECK_INODE_EXTRA_NEGATIVE_EPOCH(inode, atime)) > + inode->i_atime_extra &= ~EXT4_EPOCH_MASK; > + if (CHECK_INODE_EXTRA_NEGATIVE_EPOCH(inode, ctime)) > + inode->i_ctime_extra &= ~EXT4_EPOCH_MASK; > + if (CHECK_INODE_EXTRA_NEGATIVE_EPOCH(inode, mtime)) > + inode->i_mtime_extra &= ~EXT4_EPOCH_MASK; > + e2fsck_write_inode_full(ctx, pctx->ino, pctx->inode, > + EXT2_INODE_SIZE(sb), "pass1"); > + } > + > } > > /* > diff --git a/e2fsck/problem.c b/e2fsck/problem.c > index 897693a..b212d00 100644 > --- a/e2fsck/problem.c > +++ b/e2fsck/problem.c > @@ -1018,6 +1018,10 @@ static struct e2fsck_problem problem_table[] = { > N_("@i %i, end of extent exceeds allowed value\n\t(logical @b %c, physical @b %b, len %N)\n"), > PROMPT_CLEAR, 0 }, > > + /* Timestamp(s) on inode beyond 2310-04-04 are likely pre-1970 dates. */ > + { PR_1_EA_TIME_OUT_OF_RANGE, > + N_("Timestamp(s) on @i %i beyond 2310-04-04 are likely pre-1970 dates.\n"), > + PROMPT_FIX | PR_PREEN_OK | PR_NO_OK, 0 }, > > /* Pass 1b errors */ > > diff --git a/e2fsck/problem.h b/e2fsck/problem.h > index ae1ed26..3710638 100644 > --- a/e2fsck/problem.h > +++ b/e2fsck/problem.h > @@ -593,6 +593,10 @@ struct problem_context { > #define PR_1_EXTENT_INDEX_START_INVALID 0x01006D > > #define PR_1_EXTENT_END_OUT_OF_BOUNDS 0x01006E > + > +/* Timestamp(s) on inode beyond 2310-04-04 are likely pre-1970 dates. */ > +#define PR_1_EA_TIME_OUT_OF_RANGE 0x01006F > + > /* > * Pass 1b errors > */