Commit 9a9f3a98 authored by Baokun Li's avatar Baokun Li Committed by Theodore Ts'o
Browse files

ext4: set type of ac_groups_linear_remaining to __u32 to avoid overflow 



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: 196e402a ("ext4: improve cr 0 / cr 1 group scanning")
CC: stable@kernel.org
Signed-off-by: default avatarBaokun Li <libaokun1@huawei.com>
Reviewed-by: default avatarZhang Yi <yi.zhang@huawei.com>
Reviewed-by: default avatarJan Kara <jack@suse.cz>
Link: https://lore.kernel.org/r/20240319113325.3110393-8-libaokun1@huawei.com


Signed-off-by: default avatarTheodore Ts'o <tytso@mit.edu>
parent 63bfe841

fs/ext4/mballoc.h

+1 −1
Original line number Diff line number Diff line
@@ -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;