Re: [PATCH v2] iwlwifi: mvm: Fix a memory leak in an error handling path in 'iwl_mvm_sar_get_wgds_table()'

[Luca Coelho]

On Fri, 2017-07-14 at 12:06 +0200, Christophe JAILLET wrote:
> We should free 'wgds.pointer' here as done a few lines above in another
> error handling path.
> It was allocated within 'acpi_evaluate_object()'.
> 
> Signed-off-by: Christophe JAILLET 
> ---
> v2: rebase after 7fe90e0e3d60 ("iwlwifi: mvm: refactor geo init")

Thanks, Christophe!

I've pushed this to our internal tree and it will eventually reach the
mainline via our normal process.


> Moreovern a comment in '/drivers/acpi/acpica/utalloc.c' states that:
> /* [...] Note: The caller should use acpi_os_free to free this
>  * buffer created via ACPI_ALLOCATE_BUFFER.
>  */
> 
> So, at the end of this function:
>   out_free:
>   kfree(wgds.pointer);
> should maybe be:
>   out_free:
>   acpi_os_free(wgds.pointer);
> 
> If correct, several places should be fixed accordingly.

Thanks for pointing out! I'm about to do some refactoring in this code
and I'll make sure I check the proper way to free the acpi buffer when
doing so.

--
Cheers,
Luca.

[PATCH v2] iwlwifi: mvm: Fix a memory leak in an error handling path in 'iwl_mvm_sar_get_wgds_table()'

[Christophe JAILLET]

We should free 'wgds.pointer' here as done a few lines above in another
error handling path.
It was allocated within 'acpi_evaluate_object()'.

Signed-off-by: Christophe JAILLET 
---
v2: rebase after 7fe90e0e3d60 ("iwlwifi: mvm: refactor geo init")


Moreovern a comment in '/drivers/acpi/acpica/utalloc.c' states that:
/* [...] Note: The caller should use acpi_os_free to free this
 * buffer created via ACPI_ALLOCATE_BUFFER.
 */

So, at the end of this function:
out_free:
kfree(wgds.pointer);
should maybe be:
out_free:
acpi_os_free(wgds.pointer);

If correct, several places should be fixed accordingly.
---
 drivers/net/wireless/intel/iwlwifi/mvm/fw.c | 6 --
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/drivers/net/wireless/intel/iwlwifi/mvm/fw.c 
b/drivers/net/wireless/intel/iwlwifi/mvm/fw.c
index 79e7a7a285dc..82863e9273eb 100644
--- a/drivers/net/wireless/intel/iwlwifi/mvm/fw.c
+++ b/drivers/net/wireless/intel/iwlwifi/mvm/fw.c
@@ -1275,8 +1275,10 @@ static int iwl_mvm_sar_get_wgds_table(struct iwl_mvm 
*mvm)
 
entry = _pkg->package.elements[idx++];
if ((entry->type != ACPI_TYPE_INTEGER) ||
-   (entry->integer.value > U8_MAX))
-   return -EINVAL;
+   (entry->integer.value > U8_MAX)) {
+   ret = -EINVAL;
+   goto out_free;
+   }
 
mvm->geo_profiles[i].values[j] = entry->integer.value;
}
-- 
2.11.0