[PATCH 2/6] iwlwifi: mvm: properly check for transport data in dump

[Luca Coelho]

From: Johannes Berg <johannes.b...@intel.com>

When copying from vmalloc'ed memory to the SG list, don't crash
if the transport didn't provide any data.

Fixes: 7e62a699aafb ("iwlwifi: mvm: use dev_coredumpsg()")
Signed-off-by: Johannes Berg <johannes.b...@intel.com>
Signed-off-by: Luca Coelho <luciano.coe...@intel.com>
---
 drivers/net/wireless/intel/iwlwifi/mvm/fw-dbg.c | 11 ++++++-----
 1 file changed, 6 insertions(+), 5 deletions(-)

diff --git a/drivers/net/wireless/intel/iwlwifi/mvm/fw-dbg.c 
b/drivers/net/wireless/intel/iwlwifi/mvm/fw-dbg.c
index 2e8e3e8e30a3..067f67f74698 100644
--- a/drivers/net/wireless/intel/iwlwifi/mvm/fw-dbg.c
+++ b/drivers/net/wireless/intel/iwlwifi/mvm/fw-dbg.c
@@ -816,11 +816,12 @@ void iwl_mvm_fw_error_dump(struct iwl_mvm *mvm)
                                     sg_nents(sg_dump_data),
                                     fw_error_dump->op_mode_ptr,
                                     fw_error_dump->op_mode_len, 0);
-               sg_pcopy_from_buffer(sg_dump_data,
-                                    sg_nents(sg_dump_data),
-                                    fw_error_dump->trans_ptr->data,
-                                    fw_error_dump->trans_ptr->len,
-                                    fw_error_dump->op_mode_len);
+               if (fw_error_dump->trans_ptr)
+                       sg_pcopy_from_buffer(sg_dump_data,
+                                            sg_nents(sg_dump_data),
+                                            fw_error_dump->trans_ptr->data,
+                                            fw_error_dump->trans_ptr->len,
+                                            fw_error_dump->op_mode_len);
                dev_coredumpsg(mvm->trans->dev, sg_dump_data, file_len,
                               GFP_KERNEL);
        }
-- 
2.11.0