Merge tag 'jfs-7.1' of github.com:kleikamp/linux-shaggyHEADmaster

Pull jfs updates from Dave Kleikamp:
 "More robust data integrity checking and some fixes"

* tag 'jfs-7.1' of github.com:kleikamp/linux-shaggy:
  jfs: avoid -Wtautological-constant-out-of-range-compare warning again
  JFS: always load filesystem UUID during mount
  jfs: hold LOG_LOCK on umount to avoid null-ptr-deref
  jfs: Set the lbmDone flag at the end of lbmIODone
  jfs: fix corrupted list in dbUpdatePMap
  jfs: add dmapctl integrity check to prevent invalid operations
  jfs: add dtpage integrity check to prevent index/pointer overflows
  jfs: add dtroot integrity check to prevent index out-of-bounds

10 files changed, 344 insertions, 30 deletions

diff --git a/fs/jfs/jfs_dmap.c b/fs/jfs/jfs_dmap.c
index 2abe8cc02ee6..a841cf21da7d 100644
--- a/fs/jfs/jfs_dmap.c
+++ b/fs/jfs/jfs_dmap.c
@@ -134,6 +134,93 @@ static const s8 budtab[256] = {
 };
 
 /*
+ * check_dmapctl - Validate integrity of a dmapctl structure
+ * @dcp: Pointer to the dmapctl structure to check
+ *
+ * Return: true if valid, false if corrupted
+ */
+static bool check_dmapctl(struct dmapctl *dcp)
+{
+	s8 budmin = dcp->budmin;
+	u32 nleafs, l2nleafs, leafidx, height;
+	int i;
+
+	nleafs = le32_to_cpu(dcp->nleafs);
+	/* Check basic field ranges */
+	if (unlikely(nleafs > LPERCTL)) {
+		jfs_err("dmapctl: invalid nleafs %u (max %u)",
+			nleafs, LPERCTL);
+		return false;
+	}
+
+	l2nleafs = le32_to_cpu(dcp->l2nleafs);
+	if (unlikely(l2nleafs > L2LPERCTL)) {
+		jfs_err("dmapctl: invalid l2nleafs %u (max %u)",
+			l2nleafs, L2LPERCTL);
+		return false;
+	}
+
+	/* Verify nleafs matches l2nleafs (must be power of two) */
+	if (unlikely((1U << l2nleafs) != nleafs)) {
+		jfs_err("dmapctl: nleafs %u != 2^%u",
+			nleafs, l2nleafs);
+		return false;
+	}
+
+	leafidx = le32_to_cpu(dcp->leafidx);
+	/* Check leaf index matches expected position */
+	if (unlikely(leafidx != CTLLEAFIND)) {
+		jfs_err("dmapctl: invalid leafidx %u (expected %u)",
+			leafidx, CTLLEAFIND);
+		return false;
+	}
+
+	height = le32_to_cpu(dcp->height);
+	/* Check tree height is within valid range */
+	if (unlikely(height > (L2LPERCTL >> 1))) {
+		jfs_err("dmapctl: invalid height %u (max %u)",
+			height, L2LPERCTL >> 1);
+		return false;
+	}
+
+	/* Check budmin is valid (cannot be NOFREE for non-empty tree) */
+	if (budmin == NOFREE) {
+		if (unlikely(nleafs > 0)) {
+			jfs_err("dmapctl: budmin is NOFREE but nleafs %u",
+				nleafs);
+			return false;
+		}
+	} else if (unlikely(budmin < BUDMIN)) {
+		jfs_err("dmapctl: invalid budmin %d (min %d)",
+			budmin, BUDMIN);
+		return false;
+	}
+
+	/* Check leaf nodes fit within stree array */
+	if (unlikely(leafidx + nleafs > CTLTREESIZE)) {
+		jfs_err("dmapctl: leaf range exceeds stree size (end %u > %u)",
+			leafidx + nleafs, CTLTREESIZE);
+		return false;
+	}
+
+	/* Check leaf nodes have valid values */
+	for (i = leafidx; i < leafidx + nleafs; i++) {
+		s8 val = dcp->stree[i];
+
+		if (unlikely(val < NOFREE)) {
+			jfs_err("dmapctl: invalid leaf value %d at index %d",
+					val, i);
+			return false;
+		} else if (unlikely(val > 31)) {
+			jfs_err("dmapctl: leaf value %d too large at index %d", val, i);
+			return false;
+		}
+	}
+
+	return true;
+}
+
+/*
  * NAME:	dbMount()
  *
  * FUNCTION:	initializate the block allocation map.
@@ -1372,7 +1459,7 @@ dbAllocAG(struct bmap * bmp, int agno, s64 nblocks, int l2nb, s64 * results)
 	dcp = (struct dmapctl *) mp->data;
 	budmin = dcp->budmin;
 
-	if (dcp->leafidx != cpu_to_le32(CTLLEAFIND)) {
+	if (unlikely(!check_dmapctl(dcp))) {
 		jfs_error(bmp->db_ipbmap->i_sb, "Corrupt dmapctl page\n");
 		release_metapage(mp);
 		return -EIO;
@@ -1702,7 +1789,7 @@ static int dbFindCtl(struct bmap * bmp, int l2nb, int level, s64 * blkno)
 		dcp = (struct dmapctl *) mp->data;
 		budmin = dcp->budmin;
 
-		if (dcp->leafidx != cpu_to_le32(CTLLEAFIND)) {
+		if (unlikely(!check_dmapctl(dcp))) {
 			jfs_error(bmp->db_ipbmap->i_sb,
 				  "Corrupt dmapctl page\n");
 			release_metapage(mp);
@@ -2485,7 +2572,7 @@ dbAdjCtl(struct bmap * bmp, s64 blkno, int newval, int alloc, int level)
 		return -EIO;
 	dcp = (struct dmapctl *) mp->data;
 
-	if (dcp->leafidx != cpu_to_le32(CTLLEAFIND)) {
+	if (unlikely(!check_dmapctl(dcp))) {
 		jfs_error(bmp->db_ipbmap->i_sb, "Corrupt dmapctl page\n");
 		release_metapage(mp);
 		return -EIO;
@@ -3454,6 +3541,11 @@ int dbExtendFS(struct inode *ipbmap, s64 blkno,	s64 nblocks)
 		return -EIO;
 	}
 	l2dcp = (struct dmapctl *) l2mp->data;
+	if (unlikely(!check_dmapctl(l2dcp))) {
+		jfs_error(ipbmap->i_sb, "Corrupt dmapctl page\n");
+		release_metapage(l2mp);
+		return -EIO;
+	}
 
 	/* compute start L1 */
 	k = blkno >> L2MAXL1SIZE;
@@ -3471,6 +3563,10 @@ int dbExtendFS(struct inode *ipbmap, s64 blkno,	s64 nblocks)
 			if (l1mp == NULL)
 				goto errout;
 			l1dcp = (struct dmapctl *) l1mp->data;
+			if (unlikely(!check_dmapctl(l1dcp))) {
+				jfs_error(ipbmap->i_sb, "Corrupt dmapctl page\n");
+				goto errout;
+			}
 
 			/* compute start L0 */
 			j = (blkno & (MAXL1SIZE - 1)) >> L2MAXL0SIZE;
@@ -3484,6 +3580,10 @@ int dbExtendFS(struct inode *ipbmap, s64 blkno,	s64 nblocks)
 				goto errout;
 
 			l1dcp = (struct dmapctl *) l1mp->data;
+			if (unlikely(!check_dmapctl(l1dcp))) {
+				jfs_error(ipbmap->i_sb, "Corrupt dmapctl page\n");
+				goto errout;
+			}
 
 			/* compute start L0 */
 			j = 0;
@@ -3503,6 +3603,10 @@ int dbExtendFS(struct inode *ipbmap, s64 blkno,	s64 nblocks)
 				if (l0mp == NULL)
 					goto errout;
 				l0dcp = (struct dmapctl *) l0mp->data;
+				if (unlikely(!check_dmapctl(l0dcp))) {
+					jfs_error(ipbmap->i_sb, "Corrupt dmapctl page\n");
+					goto errout;
+				}
 
 				/* compute start dmap */
 				i = (blkno & (MAXL0SIZE - 1)) >>
@@ -3518,6 +3622,10 @@ int dbExtendFS(struct inode *ipbmap, s64 blkno,	s64 nblocks)
 					goto errout;
 
 				l0dcp = (struct dmapctl *) l0mp->data;
+				if (unlikely(!check_dmapctl(l0dcp))) {
+					jfs_error(ipbmap->i_sb, "Corrupt dmapctl page\n");
+					goto errout;
+				}
 
 				/* compute start dmap */
 				i = 0;
diff --git a/fs/jfs/jfs_dtree.c b/fs/jfs/jfs_dtree.c
index 9ab3f2fc61d1..ac0f79fafaca 100644
--- a/fs/jfs/jfs_dtree.c
+++ b/fs/jfs/jfs_dtree.c
@@ -115,10 +115,7 @@ struct dtsplit {
 do {									\
 	BT_GETPAGE(IP, BN, MP, dtpage_t, SIZE, P, RC, i_dtroot);	\
 	if (!(RC)) {							\
-		if (((P)->header.nextindex >				\
-		     (((BN) == 0) ? DTROOTMAXSLOT : (P)->header.maxslot)) || \
-		    ((BN) && (((P)->header.maxslot > DTPAGEMAXSLOT) ||	\
-		    ((P)->header.stblindex >= DTPAGEMAXSLOT)))) {	\
+		if ((BN) && !check_dtpage(P)) {				\
 			BT_PUTPAGE(MP);					\
 			jfs_error((IP)->i_sb,				\
 				  "DT_GETPAGE: dtree page corrupt\n");	\
@@ -4297,3 +4294,190 @@ int dtModify(tid_t tid, struct inode *ip,
 
 	return 0;
 }
+
+bool check_dtroot(dtroot_t *p)
+{
+	DECLARE_BITMAP(bitmap, DTROOTMAXSLOT) = {0};
+	int i;
+
+	/* freecnt cannot be negative or exceed DTROOTMAXSLOT-1
+	 * (since slot[0] is occupied by the header).
+	 */
+	if (unlikely(p->header.freecnt < 0 ||
+				p->header.freecnt > DTROOTMAXSLOT - 1)) {
+		jfs_err("Bad freecnt:%d in dtroot\n", p->header.freecnt);
+		return false;
+	} else if (p->header.freecnt == 0) {
+		/* No free slots: freelist must be -1 */
+		if (unlikely(p->header.freelist != -1)) {
+			jfs_err("freecnt=0, but freelist=%d in dtroot\n",
+					p->header.freelist);
+			return false;
+		}
+	} else {
+		int fsi, i;
+		/* When there are free slots, freelist must be a valid slot index in
+		 * 1~DTROOTMAXSLOT-1(since slot[0] is occupied by the header).
+		 */
+		if (unlikely(p->header.freelist < 1 ||
+					p->header.freelist >= DTROOTMAXSLOT)) {
+			jfs_err("Bad freelist:%d in dtroot\n", p->header.freelist);
+			return false;
+		}
+
+		/* Traverse the free list to check validity of all node indices */
+		fsi = p->header.freelist;
+		for (i = 0; i < p->header.freecnt - 1; i++) {
+			/* Check for duplicate indices in the free list */
+			if (unlikely(__test_and_set_bit(fsi, bitmap))) {
+				jfs_err("duplicate index%d in slot in dtroot\n", fsi);
+				return false;
+			}
+			fsi = p->slot[fsi].next;
+
+			/* Ensure the next slot index in the free list is valid */
+			if (unlikely(fsi < 1 || fsi >= DTROOTMAXSLOT)) {
+				jfs_err("Bad index:%d in slot in dtroot\n", fsi);
+				return false;
+			}
+		}
+
+		/* The last node in the free list must terminate with next = -1 */
+		if (unlikely(p->slot[fsi].next != -1)) {
+			jfs_err("Bad next:%d of the last slot in dtroot\n",
+					p->slot[fsi].next);
+			return false;
+		}
+	}
+
+	/* Validate nextindex (next free entry index in stbl)
+	 * stbl array has size 8 (indices 0~7).
+	 * It may get set to 8 when the last free slot has been filled.
+	 */
+	if (unlikely(p->header.nextindex > ARRAY_SIZE(p->header.stbl))) {
+		jfs_err("Bad nextindex:%d in dtroot\n", p->header.nextindex);
+		return false;
+	}
+
+	/* Validate index validity of stbl array (8 elements)
+	 * Each entry in stbl is a slot index, with valid range: -1 (invalid)
+	 * or 0~8 (slot[0]~slot[8])
+	 */
+	for (i = 0; i < p->header.nextindex; i++) {
+		int idx = p->header.stbl[i];
+
+		if (unlikely(idx < 0 || idx >= 9)) {
+			jfs_err("Bad index:%d of stbl[%d] in dtroot\n", idx, i);
+			return false; /* stbl entry points out of slot array range */
+		}
+
+		/* Check for duplicate valid indices (skip check for idx=0) */
+		if (unlikely(idx && __test_and_set_bit(idx, bitmap))) {
+			jfs_err("Duplicate index:%d in stbl in dtroot\n", idx);
+			return false;
+		}
+	}
+
+	return true;
+}
+
+bool check_dtpage(dtpage_t *p)
+{
+	DECLARE_BITMAP(bitmap, DTPAGEMAXSLOT) = {0};
+	const int stblsize = ((PSIZE >> L2DTSLOTSIZE) + 31) >> L2DTSLOTSIZE;
+	int i;
+
+	/* Validate maxslot (maximum number of slots in the page)
+	 * dtpage_t slot array is defined to hold up to DTPAGEMAXSLOT (128) slots
+	 */
+	if (unlikely(p->header.maxslot != DTPAGEMAXSLOT)) {
+		jfs_err("Bad maxslot:%d in dtpage (expected %d)\n",
+				p->header.maxslot, DTPAGEMAXSLOT);
+		return false;
+	}
+
+	/* freecnt cannot be negative or exceed DTPAGEMAXSLOT-1
+	 * (since slot[0] is occupied by the header).
+	 */
+	if (unlikely(p->header.freecnt < 0 ||
+				p->header.freecnt > DTPAGEMAXSLOT - 1)) {
+		jfs_err("Bad freecnt:%d in dtpage\n", p->header.freecnt);
+		return false;
+	} else if (p->header.freecnt == 0) {
+		/* No free slots: freelist must be -1 */
+		if (unlikely(p->header.freelist != -1)) {
+			jfs_err("freecnt=0 but freelist=%d in dtpage\n",
+					p->header.freelist);
+			return false;
+		}
+	} else {
+		int fsi;
+
+		if (unlikely(p->header.freelist < 1)) {
+			jfs_err("Bad freelist:%d in dtpage\n", p->header.freelist);
+			return false;
+		}
+
+		/* Traverse the free list to check validity of all node indices */
+		fsi = p->header.freelist;
+		for (i = 0; i < p->header.freecnt - 1; i++) {
+			/* Check for duplicate indices in the free list */
+			if (unlikely(__test_and_set_bit(fsi, bitmap))) {
+				jfs_err("duplicate index%d in slot in dtpage\n", fsi);
+				return false;
+			}
+			fsi = p->slot[fsi].next;
+
+			/* Ensure the next slot index in the free list is valid */
+			if (unlikely(fsi < 1 || fsi >= DTPAGEMAXSLOT)) {
+				jfs_err("Bad index:%d in slot in dtpage\n", fsi);
+				return false;
+			}
+		}
+
+		/* The last node in the free list must terminate with next = -1 */
+		if (unlikely(p->slot[fsi].next != -1)) {
+			jfs_err("Bad next:%d of the last slot in dtpage\n",
+					p->slot[fsi].next);
+			return false;
+		}
+	}
+
+	/* stbl must be little then DTPAGEMAXSLOT */
+	if (unlikely(p->header.stblindex >= DTPAGEMAXSLOT - stblsize)) {
+		jfs_err("Bad stblindex:%d in dtpage (stbl size %d)\n",
+				p->header.stblindex, stblsize);
+		return false;
+	}
+
+	/* nextindex must be little then stblsize*32 */
+	if (unlikely(p->header.nextindex > (stblsize << L2DTSLOTSIZE))) {
+		jfs_err("Bad nextindex:%d in dtpage (stbl size %d)\n",
+				p->header.nextindex, stblsize);
+		return false;
+	}
+
+	/* Validate stbl entries
+	 * Each entry is a slot index, valid range: -1 (invalid) or
+	 * [0, nextindex-1] (valid data slots)
+	 * (stblindex and higher slots are reserved for stbl itself)
+	 */
+	for (i = 0; i < p->header.nextindex; i++) {
+		int idx = DT_GETSTBL(p)[i];
+
+		/* Check if index is out of valid data slot range */
+		if (unlikely(idx < 1 || idx >= DTPAGEMAXSLOT)) {
+			jfs_err("Bad stbl[%d] index:%d (stblindex %d) in dtpage\n",
+					i, idx, p->header.stblindex);
+			return false;
+		}
+
+		/* Check for duplicate valid indices (skip -1) */
+		if (unlikely(__test_and_set_bit(idx, bitmap))) {
+			jfs_err("Duplicate index:%d in stbl of dtpage\n", idx);
+			return false;
+		}
+	}
+
+	return true;
+}
diff --git a/fs/jfs/jfs_dtree.h b/fs/jfs/jfs_dtree.h
index 1758289647a0..dfc87b6690a9 100644
--- a/fs/jfs/jfs_dtree.h
+++ b/fs/jfs/jfs_dtree.h
@@ -253,4 +253,8 @@ extern int dtModify(tid_t tid, struct inode *ip, struct component_name * key,
 		    ino_t * orig_ino, ino_t new_ino, int flag);
 
 extern int jfs_readdir(struct file *file, struct dir_context *ctx);
+
+extern bool check_dtroot(dtroot_t *p);
+
+extern bool check_dtpage(dtpage_t *p);
 #endif				/* !_H_JFS_DTREE */
diff --git a/fs/jfs/jfs_imap.c b/fs/jfs/jfs_imap.c
index 13ab21e66f51..b84ba4d7dfb4 100644
--- a/fs/jfs/jfs_imap.c
+++ b/fs/jfs/jfs_imap.c
@@ -3102,6 +3102,10 @@ static int copy_from_dinode(struct dinode * dip, struct inode *ip)
 
 	if (S_ISDIR(ip->i_mode)) {
 		memcpy(&jfs_ip->u.dir, &dip->u._dir, 384);
+		if (!check_dtroot(&jfs_ip->i_dtroot)) {
+			jfs_error(ip->i_sb, "Corrupt dtroot\n");
+			return -EIO;
+		}
 	} else if (S_ISREG(ip->i_mode) || S_ISLNK(ip->i_mode)) {
 		memcpy(&jfs_ip->i_xtroot, &dip->di_xtroot, 288);
 	} else
diff --git a/fs/jfs/jfs_logmgr.c b/fs/jfs/jfs_logmgr.c
index ada00d5bc214..306165e61438 100644
--- a/fs/jfs/jfs_logmgr.c
+++ b/fs/jfs/jfs_logmgr.c
@@ -74,12 +74,6 @@ static struct lbuf *log_redrive_list;
 static DEFINE_SPINLOCK(log_redrive_lock);
 
 
-/*
- *	log read/write serialization (per log)
- */
-#define LOG_LOCK_INIT(log)	mutex_init(&(log)->loglock)
-#define LOG_LOCK(log)		mutex_lock(&((log)->loglock))
-#define LOG_UNLOCK(log)		mutex_unlock(&((log)->loglock))
 
 
 /*
@@ -204,9 +198,13 @@ static void write_special_inodes(struct jfs_log *log,
 	struct jfs_sb_info *sbi;
 
 	list_for_each_entry(sbi, &log->sb_list, log_list) {
-		writer(sbi->ipbmap->i_mapping);
-		writer(sbi->ipimap->i_mapping);
-		writer(sbi->direct_inode->i_mapping);
+		/* These pointers can be NULL before list_del during umount */
+		if (sbi->ipbmap)
+			writer(sbi->ipbmap->i_mapping);
+		if (sbi->ipimap)
+			writer(sbi->ipimap->i_mapping);
+		if (sbi->direct_inode)
+			writer(sbi->direct_inode->i_mapping);
 	}
 }
 
@@ -2180,8 +2178,6 @@ static void lbmIODone(struct bio *bio)
 
 	LCACHE_LOCK(flags);		/* disable+lock */
 
-	bp->l_flag |= lbmDONE;
-
 	if (bio->bi_status) {
 		bp->l_flag |= lbmERROR;
 
@@ -2196,12 +2192,10 @@ static void lbmIODone(struct bio *bio)
 	if (bp->l_flag & lbmREAD) {
 		bp->l_flag &= ~lbmREAD;
 
-		LCACHE_UNLOCK(flags);	/* unlock+enable */
-
 		/* wakeup I/O initiator */
 		LCACHE_WAKEUP(&bp->l_ioevent);
 
-		return;
+		goto out;
 	}
 
 	/*
@@ -2225,8 +2219,7 @@ static void lbmIODone(struct bio *bio)
 
 	if (bp->l_flag & lbmDIRECT) {
 		LCACHE_WAKEUP(&bp->l_ioevent);
-		LCACHE_UNLOCK(flags);
-		return;
+		goto out;
 	}
 
 	tail = log->wqueue;
@@ -2278,8 +2271,6 @@ static void lbmIODone(struct bio *bio)
 	 * leave buffer for i/o initiator to dispose
 	 */
 	if (bp->l_flag & lbmSYNC) {
-		LCACHE_UNLOCK(flags);	/* unlock+enable */
-
 		/* wakeup I/O initiator */
 		LCACHE_WAKEUP(&bp->l_ioevent);
 	}
@@ -2290,6 +2281,7 @@ static void lbmIODone(struct bio *bio)
 	else if (bp->l_flag & lbmGC) {
 		LCACHE_UNLOCK(flags);
 		lmPostGC(bp);
+		LCACHE_LOCK(flags);		/* disable+lock */
 	}
 
 	/*
@@ -2302,9 +2294,11 @@ static void lbmIODone(struct bio *bio)
 		assert(bp->l_flag & lbmRELEASE);
 		assert(bp->l_flag & lbmFREE);
 		lbmfree(bp);
-
-		LCACHE_UNLOCK(flags);	/* unlock+enable */
 	}
+
+out:
+	bp->l_flag |= lbmDONE;
+	LCACHE_UNLOCK(flags);
 }
 
 int jfsIOWait(void *arg)
diff --git a/fs/jfs/jfs_logmgr.h b/fs/jfs/jfs_logmgr.h
index 8b8994e48cd0..09e0ef6aecce 100644
--- a/fs/jfs/jfs_logmgr.h
+++ b/fs/jfs/jfs_logmgr.h
@@ -403,6 +403,13 @@ struct jfs_log {
 };
 
 /*
+ * log read/write serialization (per log)
+ */
+#define LOG_LOCK_INIT(log)	mutex_init(&(log)->loglock)
+#define LOG_LOCK(log)		mutex_lock(&((log)->loglock))
+#define LOG_UNLOCK(log)		mutex_unlock(&((log)->loglock))
+
+/*
  * Log flag
  */
 #define log_INLINELOG	1
diff --git a/fs/jfs/jfs_metapage.c b/fs/jfs/jfs_metapage.c
index c95804f6dc19..41fe12e641ce 100644
--- a/fs/jfs/jfs_metapage.c
+++ b/fs/jfs/jfs_metapage.c
@@ -270,6 +270,7 @@ static inline struct metapage *alloc_metapage(gfp_t gfp_mask)
 		mp->clsn = 0;
 		mp->log = NULL;
 		init_waitqueue_head(&mp->wait);
+		INIT_LIST_HEAD(&mp->synclist);
 	}
 	return mp;
 }
@@ -379,7 +380,7 @@ static void remove_from_logsync(struct metapage *mp)
 		mp->lsn = 0;
 		mp->clsn = 0;
 		log->count--;
-		list_del(&mp->synclist);
+		list_del_init(&mp->synclist);
 	}
 	LOGSYNC_UNLOCK(log, flags);
 }
diff --git a/fs/jfs/jfs_mount.c b/fs/jfs/jfs_mount.c
index 52e6b58c5dbd..dac822f15070 100644
--- a/fs/jfs/jfs_mount.c
+++ b/fs/jfs/jfs_mount.c
@@ -378,11 +378,12 @@ static int chkSuper(struct super_block *sb)
 	sbi->nbperpage = PSIZE >> sbi->l2bsize;
 	sbi->l2nbperpage = L2PSIZE - sbi->l2bsize;
 	sbi->l2niperblk = sbi->l2bsize - L2DISIZE;
+	uuid_copy(&sbi->uuid, &j_sb->s_uuid);
+
 	if (sbi->mntflag & JFS_INLINELOG)
 		sbi->logpxd = j_sb->s_logpxd;
 	else {
 		sbi->logdev = new_decode_dev(le32_to_cpu(j_sb->s_logdev));
-		uuid_copy(&sbi->uuid, &j_sb->s_uuid);
 		uuid_copy(&sbi->loguuid, &j_sb->s_loguuid);
 	}
 	sbi->fsckpxd = j_sb->s_fsckpxd;
diff --git a/fs/jfs/jfs_txnmgr.c b/fs/jfs/jfs_txnmgr.c
index c16578af3a77..083dbbb0c326 100644
--- a/fs/jfs/jfs_txnmgr.c
+++ b/fs/jfs/jfs_txnmgr.c
@@ -275,6 +275,7 @@ int txInit(void)
 	for (k = 0; k < nTxBlock; k++) {
 		init_waitqueue_head(&TxBlock[k].gcwait);
 		init_waitqueue_head(&TxBlock[k].waitor);
+		INIT_LIST_HEAD(&TxBlock[k].synclist);
 	}
 
 	for (k = 1; k < nTxBlock - 1; k++) {
@@ -974,7 +975,7 @@ static void txUnlock(struct tblock * tblk)
 	if (tblk->lsn) {
 		LOGSYNC_LOCK(log, flags);
 		log->count--;
-		list_del(&tblk->synclist);
+		list_del_init(&tblk->synclist);
 		LOGSYNC_UNLOCK(log, flags);
 	}
 }
diff --git a/fs/jfs/jfs_umount.c b/fs/jfs/jfs_umount.c
index 8ec43f53f686..18569f1eaabd 100644
--- a/fs/jfs/jfs_umount.c
+++ b/fs/jfs/jfs_umount.c
@@ -20,6 +20,7 @@
 #include "jfs_superblock.h"
 #include "jfs_dmap.h"
 #include "jfs_imap.h"
+#include "jfs_logmgr.h"
 #include "jfs_metapage.h"
 #include "jfs_debug.h"
 
@@ -58,6 +59,12 @@ int jfs_umount(struct super_block *sb)
 		jfs_flush_journal(log, 2);
 
 	/*
+	 * Hold log lock so write_special_inodes (lmLogSync) cannot see
+	 * this sbi with a NULL inode pointer while iterating log->sb_list.
+	 */
+	if (log)
+		LOG_LOCK(log);
+	/*
 	 * close fileset inode allocation map (aka fileset inode)
 	 */
 	diUnmount(ipimap, 0);
@@ -95,6 +102,9 @@ int jfs_umount(struct super_block *sb)
 	 */
 	filemap_write_and_wait(sbi->direct_inode->i_mapping);
 
+	if (log)
+		LOG_UNLOCK(log);
+
 	/*
 	 * ensure all file system file pages are propagated to their
 	 * home blocks on disk (and their in-memory buffer pages are