From: Arnd Bergmann <arnd@xxxxxxxx>
clang points out a potential issue with integer overflow when
the iwl_dev_info_table[] array is empty:
drivers/net/wireless/intel/iwlwifi/pcie/drv.c:1344:42: error: implicit conversion from 'unsigned long' to 'int' changes value from 18446744073709551615 to -1 [-Werror,-Wconstant-conversion]
for (i = ARRAY_SIZE(iwl_dev_info_table) - 1; i >= 0; i--) {
~ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~^~~
This is still harmless, as the loop correctly terminates, but adding
an extra range check makes that obvious to both readers and to the
compiler.
Fixes: 3f7320428fa4 ("iwlwifi: pcie: simplify iwl_pci_find_dev_info()")
Reported-by: kernel test robot <lkp@xxxxxxxxx>
Cc: Nick Desaulniers <ndesaulniers@xxxxxxxxxx>
Signed-off-by: Arnd Bergmann <arnd@xxxxxxxx>
---
Changes in v2:
- replace int cast with a range check
---
drivers/net/wireless/intel/iwlwifi/pcie/drv.c | 3 +++
1 file changed, 3 insertions(+)
diff --git a/drivers/net/wireless/intel/iwlwifi/pcie/drv.c b/drivers/net/wireless/intel/iwlwifi/pcie/drv.c
index c574f041f096..fcda7603024b 100644
--- a/drivers/net/wireless/intel/iwlwifi/pcie/drv.c
+++ b/drivers/net/wireless/intel/iwlwifi/pcie/drv.c
@@ -1341,6 +1341,9 @@ iwl_pci_find_dev_info(u16 device, u16 subsystem_device,
{
int i;
+ if (ARRAY_SIZE(iwl_dev_info_table) == 0)
+ return NULL;
+
for (i = ARRAY_SIZE(iwl_dev_info_table) - 1; i >= 0; i--) {
const struct iwl_dev_info *dev_info = &iwl_dev_info_table[i];
--
2.29.2
