Now ac_groups_linear_remaining is of type __u16 and s_mb_max_linear_groups is of type unsigned int, so an overflow occurs when setting a value above 65535 through the mb_max_linear_groups sysfs interface. Therefore, the type of ac_groups_linear_remaining is set to __u32 to avoid overflow. Fixes: 196e402adf2e ("ext4: improve cr 0 / cr 1 group scanning") CC: stable@xxxxxxxxxx Signed-off-by: Baokun Li <libaokun1@xxxxxxxxxx> Reviewed-by: Zhang Yi <yi.zhang@xxxxxxxxxx> Reviewed-by: Jan Kara <jack@xxxxxxx> --- fs/ext4/mballoc.h | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/fs/ext4/mballoc.h b/fs/ext4/mballoc.h index 56938532b4ce..7bfc5fb5a128 100644 --- a/fs/ext4/mballoc.h +++ b/fs/ext4/mballoc.h @@ -193,8 +193,8 @@ struct ext4_allocation_context { ext4_grpblk_t ac_orig_goal_len; __u32 ac_flags; /* allocation hints */ + __u32 ac_groups_linear_remaining; __u16 ac_groups_scanned; - __u16 ac_groups_linear_remaining; __u16 ac_found; __u16 ac_cX_found[EXT4_MB_NUM_CRS]; __u16 ac_tail; -- 2.31.1