diff --git a/fs/jfs/jfs_discard.c b/fs/jfs/jfs_discard.c
index 575cb2ba74fc..5f4b305030ad 100644
--- a/fs/jfs/jfs_discard.c
+++ b/fs/jfs/jfs_discard.c
@@ -65,7 +65,7 @@ void jfs_issue_discard(struct inode *ip, u64 blkno, u64 nblocks)
 int jfs_ioc_trim(struct inode *ip, struct fstrim_range *range)
 {
 	struct inode *ipbmap = JFS_SBI(ip->i_sb)->ipbmap;
-	struct bmap *bmp = JFS_SBI(ip->i_sb)->bmap;
+	struct bmap *bmp;
 	struct super_block *sb = ipbmap->i_sb;
 	int agno, agno_end;
 	u64 start, end, minlen;
@@ -83,10 +83,15 @@ int jfs_ioc_trim(struct inode *ip, struct fstrim_range *range)
 	if (minlen == 0)
 		minlen = 1;
 
+	down_read(&sb->s_umount);
+	bmp = JFS_SBI(ip->i_sb)->bmap;
+
 	if (minlen > bmp->db_agsize ||
 	    start >= bmp->db_mapsize ||
-	    range->len < sb->s_blocksize)
+	    range->len < sb->s_blocksize) {
+		up_read(&sb->s_umount);
 		return -EINVAL;
+	}
 
 	if (end >= bmp->db_mapsize)
 		end = bmp->db_mapsize - 1;
@@ -100,6 +105,8 @@ int jfs_ioc_trim(struct inode *ip, struct fstrim_range *range)
 		trimmed += dbDiscardAG(ip, agno, minlen);
 		agno++;
 	}
+
+	up_read(&sb->s_umount);
 	range->len = trimmed << sb->s_blocksize_bits;
 
 	return 0;
diff --git a/fs/jfs/jfs_dmap.c b/fs/jfs/jfs_dmap.c
index 5713994328cb..974ecf5e0d95 100644
--- a/fs/jfs/jfs_dmap.c
+++ b/fs/jfs/jfs_dmap.c
@@ -187,7 +187,7 @@ int dbMount(struct inode *ipbmap)
 	}
 
 	bmp->db_numag = le32_to_cpu(dbmp_le->dn_numag);
-	if (!bmp->db_numag) {
+	if (!bmp->db_numag || bmp->db_numag >= MAXAG) {
 		err = -EINVAL;
 		goto err_release_metapage;
 	}
@@ -652,7 +652,7 @@ int dbNextAG(struct inode *ipbmap)
 	 * average free space.
 	 */
 	for (i = 0 ; i < bmp->db_numag; i++, agpref++) {
-		if (agpref == bmp->db_numag)
+		if (agpref >= bmp->db_numag)
 			agpref = 0;
 
 		if (atomic_read(&bmp->db_active[agpref]))
@@ -2944,9 +2944,10 @@ static void dbAdjTree(dmtree_t *tp, int leafno, int newval, bool is_ctl)
 static int dbFindLeaf(dmtree_t *tp, int l2nb, int *leafidx, bool is_ctl)
 {
 	int ti, n = 0, k, x = 0;
-	int max_size;
+	int max_size, max_idx;
 
 	max_size = is_ctl ? CTLTREESIZE : TREESIZE;
+	max_idx = is_ctl ? LPERCTL : LPERDMAP;
 
 	/* first check the root of the tree to see if there is
 	 * sufficient free space.
@@ -2978,6 +2979,8 @@ static int dbFindLeaf(dmtree_t *tp, int l2nb, int *leafidx, bool is_ctl)
 		 */
 		assert(n < 4);
 	}
+	if (le32_to_cpu(tp->dmt_leafidx) >= max_idx)
+		return -ENOSPC;
 
 	/* set the return to the leftmost leaf describing sufficient
 	 * free space.
@@ -3022,7 +3025,7 @@ static int dbFindBits(u32 word, int l2nb)
 
 	/* scan the word for nb free bits at nb alignments.
 	 */
-	for (bitno = 0; mask != 0; bitno += nb, mask >>= nb) {
+	for (bitno = 0; mask != 0; bitno += nb, mask = (mask >> nb)) {
 		if ((mask & word) == mask)
 			break;
 	}
diff --git a/fs/jfs/jfs_imap.c b/fs/jfs/jfs_imap.c
index 1407feccbc2d..a360b24ed320 100644
--- a/fs/jfs/jfs_imap.c
+++ b/fs/jfs/jfs_imap.c
@@ -1360,7 +1360,7 @@ int diAlloc(struct inode *pip, bool dir, struct inode *ip)
 	/* get the ag number of this iag */
 	agno = BLKTOAG(JFS_IP(pip)->agstart, JFS_SBI(pip->i_sb));
 	dn_numag = JFS_SBI(pip->i_sb)->bmap->db_numag;
-	if (agno < 0 || agno > dn_numag)
+	if (agno < 0 || agno > dn_numag || agno >= MAXAG)
 		return -EIO;
 
 	if (atomic_read(&JFS_SBI(pip->i_sb)->bmap->db_active[agno])) {
diff --git a/fs/jfs/xattr.c b/fs/jfs/xattr.c
index 2999ed5d83f5..0fb05e314edf 100644
--- a/fs/jfs/xattr.c
+++ b/fs/jfs/xattr.c
@@ -434,6 +434,8 @@ static int ea_get(struct inode *inode, struct ea_buffer *ea_buf, int min_size)
 	int rc;
 	int quota_allocation = 0;
 
+	memset(&ea_buf->new_ea, 0, sizeof(ea_buf->new_ea));
+
 	/* When fsck.jfs clears a bad ea, it doesn't clear the size */
 	if (ji->ea.flag == 0)
 		ea_size = 0;