1 files changed, 10 insertions, 6 deletions

diff --git a/fs/jfs/jfs_discard.c b/fs/jfs/jfs_discard.c
index 9947563e4175..dfcd50304559 100644
--- a/fs/jfs/jfs_discard.c
+++ b/fs/jfs/jfs_discard.c
@@ -83,7 +83,7 @@ int jfs_ioc_trim(struct inode *ip, struct fstrim_range *range)
         struct bmap *bmp = JFS_SBI(ip->i_sb)->bmap;
         struct super_block *sb = ipbmap->i_sb;
         int agno, agno_end;
-        s64 start, end, minlen;
+        u64 start, end, minlen;
         u64 trimmed = 0;
 
         /**
@@ -93,15 +93,19 @@ int jfs_ioc_trim(struct inode *ip, struct fstrim_range *range)
          * minlen:      minimum extent length in Bytes
          */
         start = range->start >> sb->s_blocksize_bits;
-        if (start < 0)
-                start = 0;
         end = start + (range->len >> sb->s_blocksize_bits) - 1;
-        if (end >= bmp->db_mapsize)
-                end = bmp->db_mapsize - 1;
         minlen = range->minlen >> sb->s_blocksize_bits;
-        if (minlen <= 0)
+        if (minlen == 0)
                 minlen = 1;
 
+        if (minlen > bmp->db_agsize ||
+            start >= bmp->db_mapsize ||
+            range->len < sb->s_blocksize)
+                return -EINVAL;
+
+        if (end >= bmp->db_mapsize)
+                end = bmp->db_mapsize - 1;
+
         /**
          * we trim all ag's within the range
          */