1 files changed, 4 insertions, 1 deletions

diff --git a/fs/ext4/super.c b/fs/ext4/super.c
index 874dd25b7481..266174b268cc 100644
--- a/fs/ext4/super.c
+++ b/fs/ext4/super.c
@@ -4458,6 +4458,7 @@ static int ext4_statfs(struct dentry *dentry, struct kstatfs *buf)
         struct ext4_sb_info *sbi = EXT4_SB(sb);
         struct ext4_super_block *es = sbi->s_es;
         u64 fsid;
+        s64 bfree;
 
         if (test_opt(sb, MINIX_DF)) {
                 sbi->s_overhead_last = 0;
@@ -4501,8 +4502,10 @@ static int ext4_statfs(struct dentry *dentry, struct kstatfs *buf)
         buf->f_type = EXT4_SUPER_MAGIC;
         buf->f_bsize = sb->s_blocksize;
         buf->f_blocks = ext4_blocks_count(es) - sbi->s_overhead_last;
-        buf->f_bfree = percpu_counter_sum_positive(&sbi->s_freeblocks_counter) -
+        bfree = percpu_counter_sum_positive(&sbi->s_freeblocks_counter) -
                        percpu_counter_sum_positive(&sbi->s_dirtyblocks_counter);
+        /* prevent underflow in case that few free space is available */
+        buf->f_bfree = max_t(s64, bfree, 0);
         buf->f_bavail = buf->f_bfree - ext4_r_blocks_count(es);
         if (buf->f_bfree < ext4_r_blocks_count(es))
                 buf->f_bavail = 0;