kevin/linux
1
Fork 0
Code

ext4: avoid negative min_clusters in find_group_orlov()

Browse Source 
min_clusters is signed integer and will be converted to unsigned
integer when compared with unsigned number stats.free_clusters.
If min_clusters is negative, it will be converted to a huge unsigned
value in which case all groups may not meet the actual desired free
clusters.
Set negative min_clusters to 0 to avoid unexpected behavior.

Fixes: ac27a0ec11 ("[PATCH] ext4: initial copy of files from ext3")
Signed-off-by: Kemeng Shi <shikemeng@huaweicloud.com>
Link: https://patch.msgid.link/20240820132234.2759926-4-shikemeng@huaweicloud.com
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
This commit is contained in:
Kemeng Shi 2024-08-20 21:22:30 +08:00 committed by Theodore Ts'o
parent 227d31b921
commit bb0a12c343
1 changed files with 2 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

2
fs/ext4/ialloc.c
View File

@ -514,6 +514,8 @@ static int find_group_orlov(struct super_block *sb, struct inode *parent,
if (min_inodes < 1)
min_inodes = 1;
min_clusters = avefreec - EXT4_CLUSTERS_PER_GROUP(sb)*flex_size / 4;
if (min_clusters < 0)
min_clusters = 0;
/*
* Start looking in the flex group where we last allocated an