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Date: Wed, 18 Mar 2015 15:15:32 -0500
From: Eric Sandeen <sandeen@...hat.com>
To: ext4 development <linux-ext4@...r.kernel.org>
CC: Jan Kara <jack@...e.cz>
Subject: [PATCH] e2fsck: completely ignore last-mount and last-write within
fudge_time
In some cases, particularly with RTC set to localtime, we may have
timestamps in the superblock off by up to 24 hours.
Today, even if accept_time_fudge is set, we find the problem, alert
the user, fix it, and set E2F_FLAG_PROBLEMS_FIXED in fix_problem().
This flag causes check_if_skip() to return (not exit), and a full
check ensues. This will happen on every single boot.
This runs counter to what the man page implies; the text there sounds
like time offsets of up to 24h will be ignored. But in truth, the
only difference accept_time_fudge makes today is to change the message
presented to the user. Actual action taken by e2fsck is identical.
So: Change the code so that last-mount and last-write times are
completely ignored if they are within 24h (the fudge_time), and
clarify the man page to show that this is the case.
If accept_fudge_time is set to false, ctx->fudge_time will be 0,
and no leeway will be given.
(As a historical note, both Fedora and OpenSUSE had set
broken_system_clock to 1 to work around this behavior in the past,
but that defeated all time-based checks).
Signed-off-by: Eric Sandeen <sandeen@...hat.com>
---
diff --git a/e2fsck/e2fsck.conf.5.in b/e2fsck/e2fsck.conf.5.in
index 9ebfbbf..515af37 100644
--- a/e2fsck/e2fsck.conf.5.in
+++ b/e2fsck/e2fsck.conf.5.in
@@ -103,6 +103,7 @@ buggy or misconfigured virtualization manager or the
installer not having access to a network time server
during the installation process. So by default, we allow
the superblock times to be fudged by up to 24 hours.
+No repair action will be taken in this case.
This can be disabled by setting
.I accept_time_fudge
to the
diff --git a/e2fsck/problem.c b/e2fsck/problem.c
index a63e61c..c05ba4b 100644
--- a/e2fsck/problem.c
+++ b/e2fsck/problem.c
@@ -383,18 +383,6 @@ static struct e2fsck_problem problem_table[] = {
N_("The test_fs flag is set (and ext4 is available). "),
PROMPT_CLEAR, PR_PREEN_OK },
- /* Last mount time is in the future (fudged) */
- { PR_0_FUTURE_SB_LAST_MOUNT_FUDGED,
- N_("@S last mount time is in the future.\n\t(by less than a day, "
- "probably due to the hardware clock being incorrectly set) "),
- PROMPT_FIX, PR_PREEN_OK | PR_NO_OK },
-
- /* Last write time is in the future (fudged) */
- { PR_0_FUTURE_SB_LAST_WRITE_FUDGED,
- N_("@S last write time is in the future.\n\t(by less than a day, "
- "probably due to the hardware clock being incorrectly set). "),
- PROMPT_FIX, PR_PREEN_OK | PR_NO_OK },
-
/* Block group checksum (latch question) is invalid. */
{ PR_0_GDT_CSUM_LATCH,
N_("One or more @b @g descriptor checksums are invalid. "),
diff --git a/e2fsck/problem.h b/e2fsck/problem.h
index 3c28166..4e8d76e 100644
--- a/e2fsck/problem.h
+++ b/e2fsck/problem.h
@@ -219,11 +219,11 @@ struct problem_context {
/* The test_fs filesystem flag is set and ext4 is available */
#define PR_0_CLEAR_TESTFS_FLAG 0x00003B
-/* Last mount time is in the future (fudged) */
-#define PR_0_FUTURE_SB_LAST_MOUNT_FUDGED 0x00003C
+/* Last mount time is in the future (fudged) -- NO LONGER USED */
+/* #define PR_0_FUTURE_SB_LAST_MOUNT_FUDGED 0x00003C */
-/* Last write time is in the future (fudged) */
-#define PR_0_FUTURE_SB_LAST_WRITE_FUDGED 0x00003D
+/* Last write time is in the future (fudged) -- NO LONGER USED */
+/* #define PR_0_FUTURE_SB_LAST_WRITE_FUDGED 0x00003D */
/* Block group checksum (latch question) */
#define PR_0_GDT_CSUM_LATCH 0x00003E
diff --git a/e2fsck/super.c b/e2fsck/super.c
index 1e7e749..4d7a3bf 100644
--- a/e2fsck/super.c
+++ b/e2fsck/super.c
@@ -856,11 +856,9 @@ void check_super_block(e2fsck_t ctx)
*/
if (!broken_system_clock &&
!(ctx->flags & E2F_FLAG_TIME_INSANE) &&
- fs->super->s_mtime > (__u32) ctx->now) {
+ fs->super->s_mtime > (__u32) ctx->now + ctx->time_fudge) {
pctx.num = fs->super->s_mtime;
problem = PR_0_FUTURE_SB_LAST_MOUNT;
- if (fs->super->s_mtime <= (__u32) ctx->now + ctx->time_fudge)
- problem = PR_0_FUTURE_SB_LAST_MOUNT_FUDGED;
if (fix_problem(ctx, problem, &pctx)) {
fs->super->s_mtime = ctx->now;
fs->flags |= EXT2_FLAG_DIRTY;
@@ -868,11 +866,9 @@ void check_super_block(e2fsck_t ctx)
}
if (!broken_system_clock &&
!(ctx->flags & E2F_FLAG_TIME_INSANE) &&
- fs->super->s_wtime > (__u32) ctx->now) {
+ fs->super->s_wtime > (__u32) ctx->now + ctx->time_fudge) {
pctx.num = fs->super->s_wtime;
problem = PR_0_FUTURE_SB_LAST_WRITE;
- if (fs->super->s_wtime <= (__u32) ctx->now + ctx->time_fudge)
- problem = PR_0_FUTURE_SB_LAST_WRITE_FUDGED;
if (fix_problem(ctx, problem, &pctx)) {
fs->super->s_wtime = ctx->now;
fs->flags |= EXT2_FLAG_DIRTY;
--
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