ext4: add sanity check to ext4_get_group_info()

The group number passed to ext4_get_group_info() should be valid, but
let's add an assert to check this before we start creating a pointer
based on that group number and dereferencing it.

Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
This commit is contained in:
Theodore Ts'o 2013-06-06 11:16:43 -04:00
parent b302ef2d3c
commit 2f2e09eb15

View File

@ -2313,6 +2313,7 @@ struct ext4_group_info *ext4_get_group_info(struct super_block *sb,
{
struct ext4_group_info ***grp_info;
long indexv, indexh;
BUG_ON(group >= EXT4_SB(sb)->s_groups_count);
grp_info = EXT4_SB(sb)->s_group_info;
indexv = group >> (EXT4_DESC_PER_BLOCK_BITS(sb));
indexh = group & ((EXT4_DESC_PER_BLOCK(sb)) - 1);