fsck.ubifs: Replay journal

This is the 2/18 step of fsck. Replay journal, update TNC & LPT.
There could be following steps and possible errors:
 Step 1. scan log LEB, get all bud LEBs
  a. corrupted scanning data in log area: danger mode with rebuild_fs and
     normal mode with 'yes' answer will turn to rebuild filesystem, other
     modes will exit.
 Step 2. scan bud LEBs, get all nodes
  a. corrupted scanning data in bud LEB: danger mode and normal mode with
     'yes' answer will drop bud LEB and set %FR_LPT_INCORRECT for lpt
     status, other modes will exit.
 Step 3. apply nodes, record latest isize into size_tree
 Step 4. apply nodes, update TNC & LPT
  a. corrupted data searched from TNC: skip node and set %FR_LPT_INCORRECT
     lpt status for danger mode and normal mode with 'yes' answer, other
     modes will exit.
  b. corrupted index node read from TNC: danger mode with rebuild_fs and
     normal mode with 'yes' answer will turn to rebuild filesystem, other
     modes will exit.
  c. corrupted lpt: Set %FR_LPT_CORRUPTED for lpt status. Ignore the
     error.
  d. incorrect lpt: Set %FR_LPT_INCORRECT for lpt status. Ignore the
     error.
  e. If lpt status is not empty, skip updating lpt.

Signed-off-by: Zhihao Cheng <chengzhihao1@huawei.com>
Signed-off-by: David Oberhollenzer <david.oberhollenzer@sigma-star.at>

1 files changed, 47 insertions, 7 deletions

diff --git a/ubifs-utils/libubifs/replay.c b/ubifs-utils/libubifs/replay.c
index 30ed282..2741742 100644
--- a/ubifs-utils/libubifs/replay.c
+++ b/ubifs-utils/libubifs/replay.c
@@ -94,11 +94,18 @@ static int set_bud_lprops(struct ubifs_info *c, struct bud_entry *b)
 	const struct ubifs_lprops *lp;
 	int err = 0, dirty;
 
+	if (!test_lpt_valid_callback(c, b->bud->lnum, LPROPS_NC, LPROPS_NC,
+				     LPROPS_NC, LPROPS_NC))
+		return 0;
+
 	ubifs_get_lprops(c);
 
 	lp = ubifs_lpt_lookup_dirty(c, b->bud->lnum);
 	if (IS_ERR(lp)) {
 		err = PTR_ERR(lp);
+		if (test_and_clear_failure_reason_callback(c, FR_LPT_CORRUPTED) &&
+		    can_ignore_failure_callback(c, FR_LPT_CORRUPTED))
+			err = 0;
 		goto out;
 	}
 
@@ -140,6 +147,10 @@ static int set_bud_lprops(struct ubifs_info *c, struct bud_entry *b)
 				b->bud->lnum, lp->free, lp->dirty, b->free,
 				b->dirty);
 	}
+	if (!test_lpt_valid_callback(c, b->bud->lnum, lp->free, lp->dirty,
+				     b->free, dirty + b->dirty))
+		goto out;
+
 	lp = ubifs_change_lp(c, lp, b->free, dirty + b->dirty,
 			     lp->flags | LPROPS_TAKEN, 0);
 	if (IS_ERR(lp)) {
@@ -766,6 +777,7 @@ out:
 	return err;
 
 out_dump:
+	set_failure_reason_callback(c, FR_DATA_CORRUPTED);
 	ubifs_err(c, "bad node is at LEB %d:%d", lnum, snod->offs);
 	ubifs_dump_node(c, snod->node, c->leb_size - snod->offs);
 	ubifs_scan_destroy(sleb);
@@ -781,14 +793,24 @@ out_dump:
  */
 static int replay_buds(struct ubifs_info *c)
 {
-	struct bud_entry *b;
+	struct bud_entry *b, *tmp_b;
 	int err;
 	unsigned long long prev_sqnum = 0;
 
-	list_for_each_entry(b, &c->replay_buds, list) {
+	list_for_each_entry_safe(b, tmp_b, &c->replay_buds, list) {
 		err = replay_bud(c, b);
-		if (err)
+		if (err) {
+			if (test_and_clear_failure_reason_callback(c, FR_DATA_CORRUPTED) &&
+			    handle_failure_callback(c, FR_H_BUD_CORRUPTED, b->bud)) {
+				/* Set %FR_LPT_INCORRECT for lpt status. */
+				set_lpt_invalid_callback(c, FR_LPT_INCORRECT);
+				/* Skip replaying the bud LEB. */
+				list_del(&b->list);
+				kfree(b);
+				continue;
+			}
 			return err;
+		}
 
 		ubifs_assert(c, b->sqnum > prev_sqnum);
 		prev_sqnum = b->sqnum;
@@ -1062,6 +1084,7 @@ out:
 	return err;
 
 out_dump:
+	set_failure_reason_callback(c, FR_DATA_CORRUPTED);
 	ubifs_err(c, "log error detected while replaying the log at LEB %d:%d",
 		  lnum, offs + snod->offs);
 	ubifs_dump_node(c, snod->node, c->leb_size - snod->offs);
@@ -1086,11 +1109,20 @@ static int take_ihead(struct ubifs_info *c)
 	lp = ubifs_lpt_lookup_dirty(c, c->ihead_lnum);
 	if (IS_ERR(lp)) {
 		err = PTR_ERR(lp);
+		if (test_and_clear_failure_reason_callback(c, FR_LPT_CORRUPTED) &&
+		    can_ignore_failure_callback(c, FR_LPT_CORRUPTED))
+			err = 0;
 		goto out;
 	}
 
 	free = lp->free;
 
+	if (!test_lpt_valid_callback(c, c->ihead_lnum, LPROPS_NC, LPROPS_NC,
+				     LPROPS_NC, LPROPS_NC)) {
+		err = free;
+		goto out;
+	}
+
 	lp = ubifs_change_lp(c, lp, LPROPS_NC, LPROPS_NC,
 			     lp->flags | LPROPS_TAKEN, 0);
 	if (IS_ERR(lp)) {
@@ -1123,10 +1155,17 @@ int ubifs_replay_journal(struct ubifs_info *c)
 	if (free < 0)
 		return free; /* Error code */
 
-	if (c->ihead_offs != c->leb_size - free) {
-		ubifs_err(c, "bad index head LEB %d:%d", c->ihead_lnum,
-			  c->ihead_offs);
-		return -EINVAL;
+	if (c->program_type != FSCK_PROGRAM_TYPE) {
+		/*
+		 * Skip index head checking for fsck, it is hard to check it
+		 * caused by possible corrupted/incorrect lpt, tnc updating
+		 * will report error code if index tree is really corrupted.
+		 */
+		if (c->ihead_offs != c->leb_size - free) {
+			ubifs_err(c, "bad index head LEB %d:%d", c->ihead_lnum,
+				  c->ihead_offs);
+			return -EINVAL;
+		}
 	}
 
 	dbg_mnt("start replaying the journal");
@@ -1147,6 +1186,7 @@ int ubifs_replay_journal(struct ubifs_info *c)
 			 * something went wrong and we cannot proceed mounting
 			 * the file-system.
 			 */
+			set_failure_reason_callback(c, FR_DATA_CORRUPTED);
 			ubifs_err(c, "no UBIFS nodes found at the log head LEB %d:%d, possibly corrupted",
 				  lnum, 0);
 			err = -EINVAL;