From 0f3086868e8889a823a6e0f3d299102aa895d947 Mon Sep 17 00:00:00 2001 From: Stefano Brivio Date: Fri, 25 Aug 2017 22:48:48 +0200 Subject: [PATCH] cxgb4: Fix stack out-of-bounds read due to wrong size to t4_record_mbox() Passing commands for logging to t4_record_mbox() with size MBOX_LEN, when the actual command size is actually smaller, causes out-of-bounds stack accesses in t4_record_mbox() while copying command words here: for (i = 0; i < size / 8; i++) entry->cmd[i] = be64_to_cpu(cmd[i]); Up to 48 bytes from the stack are then leaked to debugfs. This happens whenever we send (and log) commands described by structs fw_sched_cmd (32 bytes leaked), fw_vi_rxmode_cmd (48), fw_hello_cmd (48), fw_bye_cmd (48), fw_initialize_cmd (48), fw_reset_cmd (48), fw_pfvf_cmd (32), fw_eq_eth_cmd (16), fw_eq_ctrl_cmd (32), fw_eq_ofld_cmd (32), fw_acl_mac_cmd(16), fw_rss_glb_config_cmd(32), fw_rss_vi_config_cmd(32), fw_devlog_cmd(32), fw_vi_enable_cmd(48), fw_port_cmd(32), fw_sched_cmd(32), fw_devlog_cmd(32). The cxgb4vf driver got this right instead. When we call t4_record_mbox() to log a command reply, a MBOX_LEN size can be used though, as get_mbox_rpl() will fill cmd_rpl up completely. Fixes: 7f080c3f2ff0 ("cxgb4: Add support to enable logging of firmware mailbox commands") Signed-off-by: Stefano Brivio Signed-off-by: David S. Miller --- drivers/net/ethernet/chelsio/cxgb4/t4_hw.c | 6 +++--- 1 file changed, 3 insertions(+), 3 deletions(-) diff --git a/drivers/net/ethernet/chelsio/cxgb4/t4_hw.c b/drivers/net/ethernet/chelsio/cxgb4/t4_hw.c index 82bf7aac6cdb..0293b41171a5 100644 --- a/drivers/net/ethernet/chelsio/cxgb4/t4_hw.c +++ b/drivers/net/ethernet/chelsio/cxgb4/t4_hw.c @@ -369,12 +369,12 @@ int t4_wr_mbox_meat_timeout(struct adapter *adap, int mbox, const void *cmd, list_del(&entry.list); spin_unlock(&adap->mbox_lock); ret = (v == MBOX_OWNER_FW) ? -EBUSY : -ETIMEDOUT; - t4_record_mbox(adap, cmd, MBOX_LEN, access, ret); + t4_record_mbox(adap, cmd, size, access, ret); return ret; } /* Copy in the new mailbox command and send it on its way ... */ - t4_record_mbox(adap, cmd, MBOX_LEN, access, 0); + t4_record_mbox(adap, cmd, size, access, 0); for (i = 0; i < size; i += 8) t4_write_reg64(adap, data_reg + i, be64_to_cpu(*p++)); @@ -426,7 +426,7 @@ int t4_wr_mbox_meat_timeout(struct adapter *adap, int mbox, const void *cmd, } ret = (pcie_fw & PCIE_FW_ERR_F) ? -ENXIO : -ETIMEDOUT; - t4_record_mbox(adap, cmd, MBOX_LEN, access, ret); + t4_record_mbox(adap, cmd, size, access, ret); dev_err(adap->pdev_dev, "command %#x in mailbox %d timed out\n", *(const u8 *)cmd, mbox); t4_report_fw_error(adap); -- 2.30.2