If inode bitmap block and block bitmap block are in different group, there is a risk to access uninitialized block_cluster in ext4_num_overhead_clusters. Initialize block_cluster to -1 to fix this. Signed-off-by: Kemeng Shi <shikemeng@xxxxxxxxxxxxxxx> Reported-by: kernel test robot <lkp@xxxxxxxxx> Reported-by: Dan Carpenter <error27@xxxxxxxxx> Link: https://lore.kernel.org/r/202303171446.eLEhZzAu-lkp@xxxxxxxxx/ Fixes: e3c70113e2cb ("ext4: improve inode table blocks counting in ext4_num_overhead_clusters") --- fs/ext4/balloc.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/fs/ext4/balloc.c b/fs/ext4/balloc.c index 49fdb758b0e4..094269488183 100644 --- a/fs/ext4/balloc.c +++ b/fs/ext4/balloc.c @@ -89,7 +89,7 @@ static unsigned ext4_num_overhead_clusters(struct super_block *sb, struct ext4_group_desc *gdp) { unsigned base_clusters, num_clusters; - int block_cluster, inode_cluster; + int block_cluster = -1, inode_cluster; int itbl_cluster_start = -1, itbl_cluster_end = -1; ext4_fsblk_t start = ext4_group_first_block_no(sb, block_group); ext4_fsblk_t end = start + EXT4_BLOCKS_PER_GROUP(sb) - 1; -- 2.30.0
