adapter->dcb would get silently freed inside qlcnic_dcb_enable() in
case qlcnic_dcb_attach() would return an error, which always happens
under OOM conditions. This would lead to use-after-free because both
of the existing callers invoke qlcnic_dcb_get_info() on the obtained
pointer, which is potentially freed at that point.
Propagate errors from qlcnic_dcb_enable(), and instead free the dcb
pointer at callsite using qlcnic_dcb_free(). This also removes the now
unused qlcnic_clear_dcb_ops() helper, which was a simple wrapper around
kfree() also causing memory leaks for partially initialized dcb.
Found by Linux Verification Center (linuxtesting.org) with the SVACE
static analysis tool.
Fixes: 3c44bba1d270 ("qlcnic: Disable DCB operations from SR-IOV VFs")
Signed-off-by: Daniil Tatianin <[email protected]>
---
Changes since v1:
- Add a fixes tag + net as a target
- Remove qlcnic_clear_dcb_ops entirely & use qlcnic_dcb_free instead
---
drivers/net/ethernet/qlogic/qlcnic/qlcnic_83xx_init.c | 9 ++++++++-
drivers/net/ethernet/qlogic/qlcnic/qlcnic_dcb.h | 10 ++--------
drivers/net/ethernet/qlogic/qlcnic/qlcnic_main.c | 9 ++++++++-
3 files changed, 18 insertions(+), 10 deletions(-)
diff --git a/drivers/net/ethernet/qlogic/qlcnic/qlcnic_83xx_init.c b/drivers/net/ethernet/qlogic/qlcnic/qlcnic_83xx_init.c
index dbb800769cb6..774f2c6875ec 100644
--- a/drivers/net/ethernet/qlogic/qlcnic/qlcnic_83xx_init.c
+++ b/drivers/net/ethernet/qlogic/qlcnic/qlcnic_83xx_init.c
@@ -2505,7 +2505,14 @@ int qlcnic_83xx_init(struct qlcnic_adapter *adapter)
goto disable_mbx_intr;
qlcnic_83xx_clear_function_resources(adapter);
- qlcnic_dcb_enable(adapter->dcb);
+
+ err = qlcnic_dcb_enable(adapter->dcb);
+ if (err) {
+ qlcnic_dcb_free(adapter->dcb);
+ adapter->dcb = NULL;
+ goto disable_mbx_intr;
+ }
+
qlcnic_83xx_initialize_nic(adapter, 1);
qlcnic_dcb_get_info(adapter->dcb);
diff --git a/drivers/net/ethernet/qlogic/qlcnic/qlcnic_dcb.h b/drivers/net/ethernet/qlogic/qlcnic/qlcnic_dcb.h
index 7519773eaca6..22afa2be85fd 100644
--- a/drivers/net/ethernet/qlogic/qlcnic/qlcnic_dcb.h
+++ b/drivers/net/ethernet/qlogic/qlcnic/qlcnic_dcb.h
@@ -41,11 +41,6 @@ struct qlcnic_dcb {
unsigned long state;
};
-static inline void qlcnic_clear_dcb_ops(struct qlcnic_dcb *dcb)
-{
- kfree(dcb);
-}
-
static inline int qlcnic_dcb_get_hw_capability(struct qlcnic_dcb *dcb)
{
if (dcb && dcb->ops->get_hw_capability)
@@ -112,9 +107,8 @@ static inline void qlcnic_dcb_init_dcbnl_ops(struct qlcnic_dcb *dcb)
dcb->ops->init_dcbnl_ops(dcb);
}
-static inline void qlcnic_dcb_enable(struct qlcnic_dcb *dcb)
+static inline int qlcnic_dcb_enable(struct qlcnic_dcb *dcb)
{
- if (dcb && qlcnic_dcb_attach(dcb))
- qlcnic_clear_dcb_ops(dcb);
+ return dcb ? qlcnic_dcb_attach(dcb) : 0;
}
#endif
diff --git a/drivers/net/ethernet/qlogic/qlcnic/qlcnic_main.c b/drivers/net/ethernet/qlogic/qlcnic/qlcnic_main.c
index 28476b982bab..288eae201a31 100644
--- a/drivers/net/ethernet/qlogic/qlcnic/qlcnic_main.c
+++ b/drivers/net/ethernet/qlogic/qlcnic/qlcnic_main.c
@@ -2599,7 +2599,14 @@ qlcnic_probe(struct pci_dev *pdev, const struct pci_device_id *ent)
"Device does not support MSI interrupts\n");
if (qlcnic_82xx_check(adapter)) {
- qlcnic_dcb_enable(adapter->dcb);
+ err = qlcnic_dcb_enable(adapter->dcb);
+ if (err) {
+ qlcnic_dcb_free(adapter->dcb);
+ adapter->dcb = NULL;
+ dev_err(&pdev->dev, "Failed to enable DCB\n");
+ goto err_out_free_hw;
+ }
+
qlcnic_dcb_get_info(adapter->dcb);
err = qlcnic_setup_intr(adapter);
--
2.25.1
On Thu, Dec 22, 2022 at 10:42:23AM +0300, Daniil Tatianin wrote:
> adapter->dcb would get silently freed inside qlcnic_dcb_enable() in
> case qlcnic_dcb_attach() would return an error, which always happens
> under OOM conditions. This would lead to use-after-free because both
> of the existing callers invoke qlcnic_dcb_get_info() on the obtained
> pointer, which is potentially freed at that point.
>
> Propagate errors from qlcnic_dcb_enable(), and instead free the dcb
> pointer at callsite using qlcnic_dcb_free(). This also removes the now
> unused qlcnic_clear_dcb_ops() helper, which was a simple wrapper around
> kfree() also causing memory leaks for partially initialized dcb.
>
> Found by Linux Verification Center (linuxtesting.org) with the SVACE
> static analysis tool.
>
> Fixes: 3c44bba1d270 ("qlcnic: Disable DCB operations from SR-IOV VFs")
> Signed-off-by: Daniil Tatianin <[email protected]>
> ---
> Changes since v1:
> - Add a fixes tag + net as a target
> - Remove qlcnic_clear_dcb_ops entirely & use qlcnic_dcb_free instead
> ---
> drivers/net/ethernet/qlogic/qlcnic/qlcnic_83xx_init.c | 9 ++++++++-
> drivers/net/ethernet/qlogic/qlcnic/qlcnic_dcb.h | 10 ++--------
> drivers/net/ethernet/qlogic/qlcnic/qlcnic_main.c | 9 ++++++++-
> 3 files changed, 18 insertions(+), 10 deletions(-)
>
> diff --git a/drivers/net/ethernet/qlogic/qlcnic/qlcnic_83xx_init.c b/drivers/net/ethernet/qlogic/qlcnic/qlcnic_83xx_init.c
> index dbb800769cb6..774f2c6875ec 100644
> --- a/drivers/net/ethernet/qlogic/qlcnic/qlcnic_83xx_init.c
> +++ b/drivers/net/ethernet/qlogic/qlcnic/qlcnic_83xx_init.c
> @@ -2505,7 +2505,14 @@ int qlcnic_83xx_init(struct qlcnic_adapter *adapter)
> goto disable_mbx_intr;
>
> qlcnic_83xx_clear_function_resources(adapter);
> - qlcnic_dcb_enable(adapter->dcb);
> +
> + err = qlcnic_dcb_enable(adapter->dcb);
> + if (err) {
> + qlcnic_dcb_free(adapter->dcb);
> + adapter->dcb = NULL;
Small nit, I think qlcnic_dcb_free() already set adapter->dcb to NULL.
Otherwise, thanks for changing:
Reviewed-by: Michal Swiatkowski <[email protected]>
Thanks,
Michal
[...]
> --
> 2.25.1
On 12/22/22 12:57 PM, Michal Swiatkowski wrote:
> On Thu, Dec 22, 2022 at 10:42:23AM +0300, Daniil Tatianin wrote:
>> adapter->dcb would get silently freed inside qlcnic_dcb_enable() in
>> case qlcnic_dcb_attach() would return an error, which always happens
>> under OOM conditions. This would lead to use-after-free because both
>> of the existing callers invoke qlcnic_dcb_get_info() on the obtained
>> pointer, which is potentially freed at that point.
>>
>> Propagate errors from qlcnic_dcb_enable(), and instead free the dcb
>> pointer at callsite using qlcnic_dcb_free(). This also removes the now
>> unused qlcnic_clear_dcb_ops() helper, which was a simple wrapper around
>> kfree() also causing memory leaks for partially initialized dcb.
>>
>> Found by Linux Verification Center (linuxtesting.org) with the SVACE
>> static analysis tool.
>>
>> Fixes: 3c44bba1d270 ("qlcnic: Disable DCB operations from SR-IOV VFs")
>> Signed-off-by: Daniil Tatianin <[email protected]>
>> ---
>> Changes since v1:
>> - Add a fixes tag + net as a target
>> - Remove qlcnic_clear_dcb_ops entirely & use qlcnic_dcb_free instead
>> ---
>> drivers/net/ethernet/qlogic/qlcnic/qlcnic_83xx_init.c | 9 ++++++++-
>> drivers/net/ethernet/qlogic/qlcnic/qlcnic_dcb.h | 10 ++--------
>> drivers/net/ethernet/qlogic/qlcnic/qlcnic_main.c | 9 ++++++++-
>> 3 files changed, 18 insertions(+), 10 deletions(-)
>>
>> diff --git a/drivers/net/ethernet/qlogic/qlcnic/qlcnic_83xx_init.c b/drivers/net/ethernet/qlogic/qlcnic/qlcnic_83xx_init.c
>> index dbb800769cb6..774f2c6875ec 100644
>> --- a/drivers/net/ethernet/qlogic/qlcnic/qlcnic_83xx_init.c
>> +++ b/drivers/net/ethernet/qlogic/qlcnic/qlcnic_83xx_init.c
>> @@ -2505,7 +2505,14 @@ int qlcnic_83xx_init(struct qlcnic_adapter *adapter)
>> goto disable_mbx_intr;
>>
>> qlcnic_83xx_clear_function_resources(adapter);
>> - qlcnic_dcb_enable(adapter->dcb);
>> +
>> + err = qlcnic_dcb_enable(adapter->dcb);
>> + if (err) {
>> + qlcnic_dcb_free(adapter->dcb);
>> + adapter->dcb = NULL;
> Small nit, I think qlcnic_dcb_free() already set adapter->dcb to NULL.
Oops, you're right. Thanks for spotting.
> Otherwise, thanks for changing:
> Reviewed-by: Michal Swiatkowski <[email protected]>
>
> Thanks,
> Michal
>
> [...]
>> --
>> 2.25.1