64933ab7b0
Both db_maxag and db_agpref are used as the index of the db_agfree array, but there is currently no validity check for db_maxag and db_agpref, which can lead to errors. The following is related bug reported by Syzbot: UBSAN: array-index-out-of-bounds in fs/jfs/jfs_dmap.c:639:20 index 7936 is out of range for type 'atomic_t[128]' Add checking that the values of db_maxag and db_agpref are valid indexes for the db_agfree array. Reported-by: syzbot+38e876a8aa44b7115c76@syzkaller.appspotmail.com Closes: https://syzkaller.appspot.com/bug?extid=38e876a8aa44b7115c76 Signed-off-by: Juntong Deng <juntong.deng@outlook.com> Signed-off-by: Dave Kleikamp <dave.kleikamp@oracle.com>