From 38edd724577123c972f2264382005ac910ce747f Mon Sep 17 00:00:00 2001 From: Hannes Reinecke Date: Thu, 19 Dec 2013 14:36:11 +0100 Subject: target_core_alua: check for buffer overflow When a writing to a command-provided buffer we need to ensure that we're not writing past the end of it. At the same time we need to continue processing as typically the final data length (ie the required size of the buffer) need to be returned. Signed-off-by: Hannes Reinecke Signed-off-by: Nicholas Bellinger --- drivers/target/target_core_alua.c | 23 +++++++++++++++++------ 1 file changed, 17 insertions(+), 6 deletions(-) (limited to 'drivers/target') diff --git a/drivers/target/target_core_alua.c b/drivers/target/target_core_alua.c index e73edcad7930..12da9b386169 100644 --- a/drivers/target/target_core_alua.c +++ b/drivers/target/target_core_alua.c @@ -96,22 +96,33 @@ target_emulate_report_referrals(struct se_cmd *cmd) int pg_num; off += 4; - put_unaligned_be64(map->lba_map_first_lba, &buf[off]); + if (cmd->data_length > off) + put_unaligned_be64(map->lba_map_first_lba, &buf[off]); off += 8; - put_unaligned_be64(map->lba_map_last_lba, &buf[off]); + if (cmd->data_length > off) + put_unaligned_be64(map->lba_map_last_lba, &buf[off]); off += 8; rd_len += 20; pg_num = 0; list_for_each_entry(map_mem, &map->lba_map_mem_list, lba_map_mem_list) { - buf[off++] = map_mem->lba_map_mem_alua_state & 0x0f; + int alua_state = map_mem->lba_map_mem_alua_state; + int alua_pg_id = map_mem->lba_map_mem_alua_pg_id; + + if (cmd->data_length > off) + buf[off] = alua_state & 0x0f; + off += 2; + if (cmd->data_length > off) + buf[off] = (alua_pg_id >> 8) & 0xff; + off++; + if (cmd->data_length > off) + buf[off] = (alua_pg_id & 0xff); off++; - buf[off++] = (map_mem->lba_map_mem_alua_pg_id >> 8) & 0xff; - buf[off++] = (map_mem->lba_map_mem_alua_pg_id & 0xff); rd_len += 4; pg_num++; } - buf[desc_num] = pg_num; + if (cmd->data_length > desc_num) + buf[desc_num] = pg_num; } spin_unlock(&dev->t10_alua.lba_map_lock); -- cgit v1.2.3-70-g09d2