t7xx_port_enum_msg_handler() uses the modem-supplied port_count field as a loop bound over port_msg->data[] without checking that the message buffer contains sufficient data. A modem sending port_count=65535 in a 12-byte buffer triggers a slab-out-of-bounds read of up to 262140 bytes. Add a struct_size() check after extracting port_count and before the loop. Pass msg_len from both call sites: skb->len at the DPMAIF path after skb_pull(), and the captured rt_feature->data_len at the handshake path. Fixes: 1e3e8eb9b6e3 ("net: wwan: t7xx: Add control DMA interface") Cc: stable@vger.kernel.org Reported-by: Pavitra Jha Signed-off-by: Pavitra Jha --- drivers/net/wwan/t7xx/t7xx_modem_ops.c | 14 +++++++------- drivers/net/wwan/t7xx/t7xx_port_ctrl_msg.c | 12 +++++++++--- drivers/net/wwan/t7xx/t7xx_port_proxy.h | 2 +- 3 files changed, 17 insertions(+), 11 deletions(-) diff --git a/drivers/net/wwan/t7xx/t7xx_modem_ops.c b/drivers/net/wwan/t7xx/t7xx_modem_ops.c index 7968e208d..d0559fe16 100644 --- a/drivers/net/wwan/t7xx/t7xx_modem_ops.c +++ b/drivers/net/wwan/t7xx/t7xx_modem_ops.c @@ -453,25 +453,25 @@ static int t7xx_parse_host_rt_data(struct t7xx_fsm_ctl *ctl, struct t7xx_sys_inf { enum mtk_feature_support_type ft_spt_st, ft_spt_cfg; struct mtk_runtime_feature *rt_feature; + size_t feat_data_len; int i, offset; offset = sizeof(struct feature_query); for (i = 0; i < FEATURE_COUNT && offset < data_length; i++) { rt_feature = data + offset; - offset += sizeof(*rt_feature) + le32_to_cpu(rt_feature->data_len); - + feat_data_len = le32_to_cpu(rt_feature->data_len); + offset += sizeof(*rt_feature) + feat_data_len; ft_spt_cfg = FIELD_GET(FEATURE_MSK, core->feature_set[i]); if (ft_spt_cfg != MTK_FEATURE_MUST_BE_SUPPORTED) continue; - ft_spt_st = FIELD_GET(FEATURE_MSK, rt_feature->support_info); if (ft_spt_st != MTK_FEATURE_MUST_BE_SUPPORTED) return -EINVAL; - - if (i == RT_ID_MD_PORT_ENUM || i == RT_ID_AP_PORT_ENUM) - t7xx_port_enum_msg_handler(ctl->md, rt_feature->data); + if (i == RT_ID_MD_PORT_ENUM || i == RT_ID_AP_PORT_ENUM) { + t7xx_port_enum_msg_handler(ctl->md, rt_feature->data, + feat_data_len); + } } - return 0; } diff --git a/drivers/net/wwan/t7xx/t7xx_port_ctrl_msg.c b/drivers/net/wwan/t7xx/t7xx_port_ctrl_msg.c index ae632ef96..d984a688d 100644 --- a/drivers/net/wwan/t7xx/t7xx_port_ctrl_msg.c +++ b/drivers/net/wwan/t7xx/t7xx_port_ctrl_msg.c @@ -124,7 +124,7 @@ static int fsm_ee_message_handler(struct t7xx_port *port, struct t7xx_fsm_ctl *c * * 0 - Success. * * -EFAULT - Message check failure. */ -int t7xx_port_enum_msg_handler(struct t7xx_modem *md, void *msg) +int t7xx_port_enum_msg_handler(struct t7xx_modem *md, void *msg, size_t msg_len) { struct device *dev = &md->t7xx_dev->pdev->dev; unsigned int version, port_count, i; @@ -141,6 +141,13 @@ int t7xx_port_enum_msg_handler(struct t7xx_modem *md, void *msg) } port_count = FIELD_GET(PORT_MSG_PRT_CNT, le32_to_cpu(port_msg->info)); + + if (msg_len < struct_size(port_msg, data, port_count)) { + dev_err(dev, "Port enum msg too short: need %zu, have %zu\n", + struct_size(port_msg, data, port_count), msg_len); + return -EINVAL; + } + for (i = 0; i < port_count; i++) { u32 port_info = le32_to_cpu(port_msg->data[i]); unsigned int ch_id; @@ -154,7 +161,6 @@ int t7xx_port_enum_msg_handler(struct t7xx_modem *md, void *msg) return 0; } - static int control_msg_handler(struct t7xx_port *port, struct sk_buff *skb) { const struct t7xx_port_conf *port_conf = port->port_conf; @@ -191,7 +197,7 @@ static int control_msg_handler(struct t7xx_port *port, struct sk_buff *skb) case CTL_ID_PORT_ENUM: skb_pull(skb, sizeof(*ctrl_msg_h)); - ret = t7xx_port_enum_msg_handler(ctl->md, (struct port_msg *)skb->data); + ret = t7xx_port_enum_msg_handler(ctl->md, (struct port_msg *)skb->data, skb->len); if (!ret) ret = port_ctl_send_msg_to_md(port, CTL_ID_PORT_ENUM, 0); else diff --git a/drivers/net/wwan/t7xx/t7xx_port_proxy.h b/drivers/net/wwan/t7xx/t7xx_port_proxy.h index f0918b36e..7c3190bf0 100644 --- a/drivers/net/wwan/t7xx/t7xx_port_proxy.h +++ b/drivers/net/wwan/t7xx/t7xx_port_proxy.h @@ -103,7 +103,7 @@ void t7xx_port_proxy_reset(struct port_proxy *port_prox); void t7xx_port_proxy_uninit(struct port_proxy *port_prox); int t7xx_port_proxy_init(struct t7xx_modem *md); void t7xx_port_proxy_md_status_notify(struct port_proxy *port_prox, unsigned int state); -int t7xx_port_enum_msg_handler(struct t7xx_modem *md, void *msg); +int t7xx_port_enum_msg_handler(struct t7xx_modem *md, void *msg, size_t msg_len); int t7xx_port_proxy_chl_enable_disable(struct port_proxy *port_prox, unsigned int ch_id, bool en_flag); void t7xx_port_proxy_set_cfg(struct t7xx_modem *md, enum port_cfg_id cfg_id); -- 2.51.0