From 1304be5fe0efb42b7ec6a50dd8e1a9bce2adae17 Mon Sep 17 00:00:00 2001 From: Mike Christie Date: Thu, 26 Jan 2012 21:13:10 -0600 Subject: [SCSI] libiscsi_tcp: fix max_r2t manipulation Problem description from Xi Wang: A large max_r2t could lead to integer overflow in subsequent call to iscsi_tcp_r2tpool_alloc(), allocating a smaller buffer than expected and leading to out-of-bounds write. Signed-off-by: Mike Christie Signed-off-by: James Bottomley --- drivers/scsi/libiscsi_tcp.c | 18 ++++++++++++++++++ 1 file changed, 18 insertions(+) (limited to 'drivers/scsi/libiscsi_tcp.c') diff --git a/drivers/scsi/libiscsi_tcp.c b/drivers/scsi/libiscsi_tcp.c index 5715a3d0a3d..c4996b08199 100644 --- a/drivers/scsi/libiscsi_tcp.c +++ b/drivers/scsi/libiscsi_tcp.c @@ -1170,6 +1170,24 @@ void iscsi_tcp_r2tpool_free(struct iscsi_session *session) } EXPORT_SYMBOL_GPL(iscsi_tcp_r2tpool_free); +int iscsi_tcp_set_max_r2t(struct iscsi_conn *conn, char *buf) +{ + struct iscsi_session *session = conn->session; + unsigned short r2ts = 0; + + sscanf(buf, "%hu", &r2ts); + if (session->max_r2t == r2ts) + return 0; + + if (!r2ts || !is_power_of_2(r2ts)) + return -EINVAL; + + session->max_r2t = r2ts; + iscsi_tcp_r2tpool_free(session); + return iscsi_tcp_r2tpool_alloc(session); +} +EXPORT_SYMBOL_GPL(iscsi_tcp_set_max_r2t); + void iscsi_tcp_conn_get_stats(struct iscsi_cls_conn *cls_conn, struct iscsi_stats *stats) { -- cgit v1.2.3