iwlwifi: dbg: Mark ucode tlv data as const

The ucode TLV data may be read-only and should be treated as const
pointers, but currently a few code forcibly cast to the writable
pointer unnecessarily.  This gave developers a wrong impression as if
it can be modified, resulting in crashing regressions already a couple
of times.

This patch adds the const prefix to those cast pointers, so that such
attempt can be caught more easily in future.

Signed-off-by: Takashi Iwai <tiwai@suse.de>
Acked-by: Luca Coelho <luciano.coelho@intel.com>
Link: https://lore.kernel.org/r/20210112132449.22243-3-tiwai@suse.de
Signed-off-by: Luca Coelho <luciano.coelho@intel.com>

diff --git a/drivers/net/wireless/intel/iwlwifi/iwl-dbg-tlv.c b/drivers/net/wireless/intel/iwlwifi/iwl-dbg-tlv.c
index a80a35a..12c49fe 100644 (file)
--- a/drivers/net/wireless/intel/iwlwifi/iwl-dbg-tlv.c
+++ b/drivers/net/wireless/intel/iwlwifi/iwl-dbg-tlv.c
@@ -61,7 +61,8 @@ dbg_ver_table[IWL_DBG_TLV_TYPE_NUM] = {
        [IWL_DBG_TLV_TYPE_TRIGGER]      = {.min_ver = 1, .max_ver = 1,},
 };
 
-static int iwl_dbg_tlv_add(struct iwl_ucode_tlv *tlv, struct list_head *list)
+static int iwl_dbg_tlv_add(const struct iwl_ucode_tlv *tlv,
+                          struct list_head *list)
 {
        u32 len = le32_to_cpu(tlv->length);
        struct iwl_dbg_tlv_node *node;
@@ -76,9 +77,9 @@ static int iwl_dbg_tlv_add(struct iwl_ucode_tlv *tlv, struct list_head *list)
        return 0;
 }
 
-static bool iwl_dbg_tlv_ver_support(struct iwl_ucode_tlv *tlv)
+static bool iwl_dbg_tlv_ver_support(const struct iwl_ucode_tlv *tlv)
 {
-       struct iwl_fw_ini_header *hdr = (void *)&tlv->data[0];
+       const struct iwl_fw_ini_header *hdr = (const void *)&tlv->data[0];
        u32 type = le32_to_cpu(tlv->type);
        u32 tlv_idx = type - IWL_UCODE_TLV_DEBUG_BASE;
        u32 ver = le32_to_cpu(hdr->version);
@@ -91,9 +92,9 @@ static bool iwl_dbg_tlv_ver_support(struct iwl_ucode_tlv *tlv)
 }
 
 static int iwl_dbg_tlv_alloc_debug_info(struct iwl_trans *trans,
-                                       struct iwl_ucode_tlv *tlv)
+                                       const struct iwl_ucode_tlv *tlv)
 {
-       struct iwl_fw_ini_debug_info_tlv *debug_info = (void *)tlv->data;
+       const struct iwl_fw_ini_debug_info_tlv *debug_info = (const void *)tlv->data;
 
        if (le32_to_cpu(tlv->length) != sizeof(*debug_info))
                return -EINVAL;
@@ -105,9 +106,9 @@ static int iwl_dbg_tlv_alloc_debug_info(struct iwl_trans *trans,
 }
 
 static int iwl_dbg_tlv_alloc_buf_alloc(struct iwl_trans *trans,
-                                      struct iwl_ucode_tlv *tlv)
+                                      const struct iwl_ucode_tlv *tlv)
 {
-       struct iwl_fw_ini_allocation_tlv *alloc = (void *)tlv->data;
+       const struct iwl_fw_ini_allocation_tlv *alloc = (const void *)tlv->data;
        u32 buf_location;
        u32 alloc_id;
 
@@ -145,9 +146,9 @@ err:
 }
 
 static int iwl_dbg_tlv_alloc_hcmd(struct iwl_trans *trans,
-                                 struct iwl_ucode_tlv *tlv)
+                                 const struct iwl_ucode_tlv *tlv)
 {
-       struct iwl_fw_ini_hcmd_tlv *hcmd = (void *)tlv->data;
+       const struct iwl_fw_ini_hcmd_tlv *hcmd = (const void *)tlv->data;
        u32 tp = le32_to_cpu(hcmd->time_point);
 
        if (le32_to_cpu(tlv->length) <= sizeof(*hcmd))
@@ -169,9 +170,9 @@ static int iwl_dbg_tlv_alloc_hcmd(struct iwl_trans *trans,
 }
 
 static int iwl_dbg_tlv_alloc_region(struct iwl_trans *trans,
-                                   struct iwl_ucode_tlv *tlv)
+                                   const struct iwl_ucode_tlv *tlv)
 {
-       struct iwl_fw_ini_region_tlv *reg = (void *)tlv->data;
+       const struct iwl_fw_ini_region_tlv *reg = (const void *)tlv->data;
        struct iwl_ucode_tlv **active_reg;
        u32 id = le32_to_cpu(reg->id);
        u32 type = le32_to_cpu(reg->type);
@@ -214,9 +215,10 @@ static int iwl_dbg_tlv_alloc_region(struct iwl_trans *trans,
 }
 
 static int iwl_dbg_tlv_alloc_trigger(struct iwl_trans *trans,
-                                    struct iwl_ucode_tlv *tlv)
+                                    const struct iwl_ucode_tlv *tlv)
 {
-       struct iwl_fw_ini_trigger_tlv *trig = (void *)tlv->data;
+       const struct iwl_fw_ini_trigger_tlv *trig = (const void *)tlv->data;
+       struct iwl_fw_ini_trigger_tlv *dup_trig;
        u32 tp = le32_to_cpu(trig->time_point);
        struct iwl_ucode_tlv *dup = NULL;
        int ret;
@@ -237,8 +239,8 @@ static int iwl_dbg_tlv_alloc_trigger(struct iwl_trans *trans,
                                GFP_KERNEL);
                if (!dup)
                        return -ENOMEM;
-               trig = (void *)dup->data;
-               trig->occurrences = cpu_to_le32(-1);
+               dup_trig = (void *)dup->data;
+               dup_trig->occurrences = cpu_to_le32(-1);
                tlv = dup;
        }
 
@@ -249,7 +251,7 @@ static int iwl_dbg_tlv_alloc_trigger(struct iwl_trans *trans,
 }
 
 static int (*dbg_tlv_alloc[])(struct iwl_trans *trans,
-                             struct iwl_ucode_tlv *tlv) = {
+                             const struct iwl_ucode_tlv *tlv) = {
        [IWL_DBG_TLV_TYPE_DEBUG_INFO]   = iwl_dbg_tlv_alloc_debug_info,
        [IWL_DBG_TLV_TYPE_BUF_ALLOC]    = iwl_dbg_tlv_alloc_buf_alloc,
        [IWL_DBG_TLV_TYPE_HCMD]         = iwl_dbg_tlv_alloc_hcmd,
@@ -257,10 +259,10 @@ static int (*dbg_tlv_alloc[])(struct iwl_trans *trans,
        [IWL_DBG_TLV_TYPE_TRIGGER]      = iwl_dbg_tlv_alloc_trigger,
 };
 
-void iwl_dbg_tlv_alloc(struct iwl_trans *trans, struct iwl_ucode_tlv *tlv,
+void iwl_dbg_tlv_alloc(struct iwl_trans *trans, const struct iwl_ucode_tlv *tlv,
                       bool ext)
 {
-       struct iwl_fw_ini_header *hdr = (void *)&tlv->data[0];
+       const struct iwl_fw_ini_header *hdr = (const void *)&tlv->data[0];
        u32 type = le32_to_cpu(tlv->type);
        u32 tlv_idx = type - IWL_UCODE_TLV_DEBUG_BASE;
        u32 domain = le32_to_cpu(hdr->domain);
@@ -396,7 +398,7 @@ void iwl_dbg_tlv_free(struct iwl_trans *trans)
 static int iwl_dbg_tlv_parse_bin(struct iwl_trans *trans, const u8 *data,
                                 size_t len)
 {
-       struct iwl_ucode_tlv *tlv;
+       const struct iwl_ucode_tlv *tlv;
        u32 tlv_len;
 
        while (len >= sizeof(*tlv)) {
@@ -737,12 +739,12 @@ static void iwl_dbg_tlv_set_periodic_trigs(struct iwl_fw_runtime *fwrt)
        }
 }
 
-static bool is_trig_data_contained(struct iwl_ucode_tlv *new,
-                                  struct iwl_ucode_tlv *old)
+static bool is_trig_data_contained(const struct iwl_ucode_tlv *new,
+                                  const struct iwl_ucode_tlv *old)
 {
-       struct iwl_fw_ini_trigger_tlv *new_trig = (void *)new->data;
-       struct iwl_fw_ini_trigger_tlv *old_trig = (void *)old->data;
-       __le32 *new_data = new_trig->data, *old_data = old_trig->data;
+       const struct iwl_fw_ini_trigger_tlv *new_trig = (const void *)new->data;
+       const struct iwl_fw_ini_trigger_tlv *old_trig = (const void *)old->data;
+       const __le32 *new_data = new_trig->data, *old_data = old_trig->data;
        u32 new_dwords_num = iwl_tlv_array_len(new, new_trig, data);
        u32 old_dwords_num = iwl_tlv_array_len(old, old_trig, data);
        int i, j;

diff --git a/drivers/net/wireless/intel/iwlwifi/iwl-dbg-tlv.h b/drivers/net/wireless/intel/iwlwifi/iwl-dbg-tlv.h
index 2468238..e9f19ec 100644 (file)
--- a/drivers/net/wireless/intel/iwlwifi/iwl-dbg-tlv.h
+++ b/drivers/net/wireless/intel/iwlwifi/iwl-dbg-tlv.h
@@ -43,7 +43,7 @@ struct iwl_fw_runtime;
 
 void iwl_dbg_tlv_load_bin(struct device *dev, struct iwl_trans *trans);
 void iwl_dbg_tlv_free(struct iwl_trans *trans);
-void iwl_dbg_tlv_alloc(struct iwl_trans *trans, struct iwl_ucode_tlv *tlv,
+void iwl_dbg_tlv_alloc(struct iwl_trans *trans, const struct iwl_ucode_tlv *tlv,
                       bool ext);
 void iwl_dbg_tlv_init(struct iwl_trans *trans);
 void iwl_dbg_tlv_time_point(struct iwl_fw_runtime *fwrt,

diff --git a/drivers/net/wireless/intel/iwlwifi/iwl-drv.c b/drivers/net/wireless/intel/iwlwifi/iwl-drv.c
index 263c3c0..eb168dc 100644 (file)
--- a/drivers/net/wireless/intel/iwlwifi/iwl-drv.c
+++ b/drivers/net/wireless/intel/iwlwifi/iwl-drv.c
@@ -559,7 +559,7 @@ static int iwl_parse_tlv_firmware(struct iwl_drv *drv,
                                bool *usniffer_images)
 {
        struct iwl_tlv_ucode_header *ucode = (void *)ucode_raw->data;
-       struct iwl_ucode_tlv *tlv;
+       const struct iwl_ucode_tlv *tlv;
        size_t len = ucode_raw->size;
        const u8 *data;
        u32 tlv_len;