From: Baokun Li libaokun1@huawei.com
mainline inclusion from mainline-v6.10-rc1 commit 9a9f3a9842927e4af7ca10c19c94dad83bebd713 category: bugfix bugzilla: https://gitee.com/src-openeuler/kernel/issues/IAD018 CVE: CVE-2024-40955
Reference: https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?i...
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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@kernel.org Signed-off-by: Baokun Li libaokun1@huawei.com Reviewed-by: Zhang Yi yi.zhang@huawei.com Reviewed-by: Jan Kara jack@suse.cz Link: https://lore.kernel.org/r/20240319113325.3110393-8-libaokun1@huawei.com Signed-off-by: Theodore Ts'o tytso@mit.edu Conflicts: fs/ext4/mballoc.h [context differences] Signed-off-by: Yifan Qiao qiaoyifan4@huawei.com --- 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 d7aeb5da7d86..498af2abc5d8 100644 --- a/fs/ext4/mballoc.h +++ b/fs/ext4/mballoc.h @@ -194,8 +194,8 @@ struct ext4_allocation_context {
__u32 ac_groups_considered; __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;