From: Johannes Berg <johannes.berg@xxxxxxxxx>
[ Upstream commit 48a5494d6a4cb5812f0640d9515f1876ffc7a013 ]
If we (for example) have a trans_cfg entry in the PCI IDs table,
but then don't find a full cfg entry for it in the info table,
we fall through to the code that treats the PCI ID table entry
as a full cfg entry. This obviously causes crashes later, e.g.
when trying to build the firmware name string.
Avoid such crashes by using the low bit of the pointer as a tag
for trans_cfg entries (automatically using a macro that checks
the type when assigning) and then checking that before trying to
use the data as a full entry - if it's just a partial entry at
that point, fail.
Since we're adding some macro magic, also check that the type is
in fact either struct iwl_cfg_trans_params or struct iwl_cfg,
failing compilation ("initializer element is not constant") if
it isn't.
Signed-off-by: Johannes Berg <johannes.berg@xxxxxxxxx>
Signed-off-by: Luca Coelho <luciano.coelho@xxxxxxxxx>
Link: https://lore.kernel.org/r/iwlwifi.20210330162204.6f69fe6e4128.I921d4ae20ef5276716baeeeda0b001cf25b9b968@changeid
Signed-off-by: Luca Coelho <luciano.coelho@xxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
drivers/net/wireless/intel/iwlwifi/pcie/drv.c | 35 +++++++++++++++----
1 file changed, 28 insertions(+), 7 deletions(-)
diff --git a/drivers/net/wireless/intel/iwlwifi/pcie/drv.c b/drivers/net/wireless/intel/iwlwifi/pcie/drv.c
index 558a0b2ef0fc..6f4db04ead4a 100644
--- a/drivers/net/wireless/intel/iwlwifi/pcie/drv.c
+++ b/drivers/net/wireless/intel/iwlwifi/pcie/drv.c
@@ -17,10 +17,20 @@
#include "iwl-prph.h"
#include "internal.h"
+#define TRANS_CFG_MARKER BIT(0)
+#define _IS_A(cfg, _struct) __builtin_types_compatible_p(typeof(cfg), \
+ struct _struct)
+extern int _invalid_type;
+#define _TRANS_CFG_MARKER(cfg) \
+ (__builtin_choose_expr(_IS_A(cfg, iwl_cfg_trans_params), \
+ TRANS_CFG_MARKER, \
+ __builtin_choose_expr(_IS_A(cfg, iwl_cfg), 0, _invalid_type)))
+#define _ASSIGN_CFG(cfg) (_TRANS_CFG_MARKER(cfg) + (kernel_ulong_t)&(cfg))
+
#define IWL_PCI_DEVICE(dev, subdev, cfg) \
.vendor = PCI_VENDOR_ID_INTEL, .device = (dev), \
.subvendor = PCI_ANY_ID, .subdevice = (subdev), \
- .driver_data = (kernel_ulong_t)&(cfg)
+ .driver_data = _ASSIGN_CFG(cfg)
/* Hardware specific file defines the PCI IDs table for that hardware module */
static const struct pci_device_id iwl_hw_card_ids[] = {
@@ -1075,19 +1085,22 @@ static const struct iwl_dev_info iwl_dev_info_table[] = {
static int iwl_pci_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
{
- const struct iwl_cfg_trans_params *trans =
- (struct iwl_cfg_trans_params *)(ent->driver_data);
+ const struct iwl_cfg_trans_params *trans;
const struct iwl_cfg *cfg_7265d __maybe_unused = NULL;
struct iwl_trans *iwl_trans;
struct iwl_trans_pcie *trans_pcie;
int i, ret;
+ const struct iwl_cfg *cfg;
+
+ trans = (void *)(ent->driver_data & ~TRANS_CFG_MARKER);
+
/*
* This is needed for backwards compatibility with the old
* tables, so we don't need to change all the config structs
* at the same time. The cfg is used to compare with the old
* full cfg structs.
*/
- const struct iwl_cfg *cfg = (struct iwl_cfg *)(ent->driver_data);
+ cfg = (void *)(ent->driver_data & ~TRANS_CFG_MARKER);
/* make sure trans is the first element in iwl_cfg */
BUILD_BUG_ON(offsetof(struct iwl_cfg, trans));
@@ -1202,11 +1215,19 @@ static int iwl_pci_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
#endif
/*
- * If we didn't set the cfg yet, assume the trans is actually
- * a full cfg from the old tables.
+ * If we didn't set the cfg yet, the PCI ID table entry should have
+ * been a full config - if yes, use it, otherwise fail.
*/
- if (!iwl_trans->cfg)
+ if (!iwl_trans->cfg) {
+ if (ent->driver_data & TRANS_CFG_MARKER) {
+ pr_err("No config found for PCI dev %04x/%04x, rev=0x%x, rfid=0x%x\n",
+ pdev->device, pdev->subsystem_device,
+ iwl_trans->hw_rev, iwl_trans->hw_rf_id);
+ ret = -EINVAL;
+ goto out_free_trans;
+ }
iwl_trans->cfg = cfg;
+ }
/* if we don't have a name yet, copy name from the old cfg */
if (!iwl_trans->name)
--
2.30.2
