| Message ID | 20241014111527.2272428-3-quic_kuldsing@quicinc.com |
|---|---|
| State | New |
| Headers | show |
| Series | qcom_tzmem: Enhance Error Handling for shmbridge | expand |
On 10/16/2024 2:31 PM, Kuldeep Singh wrote: > > On 10/14/2024 6:38 PM, Bartosz Golaszewski wrote: >> On Mon, Oct 14, 2024 at 1:19 PM Kuldeep Singh <quic_kuldsing@quicinc.com> wrote: >>> >>> The qcom_tzmem driver currently has exposed APIs that lack validations >>> on required input parameters. This oversight can lead to unexpected null >>> pointer dereference crashes. >>> >> >> The commit message is not true. None of the things you changed below >> can lead to a NULL-pointer dereference.> >>> To address this issue, add sanity for required input parameters. >>> >>> Signed-off-by: Kuldeep Singh <quic_kuldsing@quicinc.com> >>> --- >>> drivers/firmware/qcom/qcom_tzmem.c | 6 ++++++ >>> 1 file changed, 6 insertions(+) >>> >>> diff --git a/drivers/firmware/qcom/qcom_tzmem.c b/drivers/firmware/qcom/qcom_tzmem.c >>> index 92b365178235..977e48fec32f 100644 >>> --- a/drivers/firmware/qcom/qcom_tzmem.c >>> +++ b/drivers/firmware/qcom/qcom_tzmem.c >>> @@ -203,6 +203,9 @@ qcom_tzmem_pool_new(const struct qcom_tzmem_pool_config *config) >>> >>> might_sleep(); >>> >>> + if (!config->policy) >>> + return ERR_PTR(-EINVAL); >> >> This is already handled by the default case of the switch. > > Ack. Need to drop. > https://elixir.bootlin.com/linux/v6.12-rc3/source/drivers/firmware/qcom/qcom_tzmem.c#L218 > > While examining qcom_tzmem_pool_free under the same principle, it > appears the following check is unnecessary. > https://elixir.bootlin.com/linux/v6.12-rc3/source/drivers/firmware/qcom/qcom_tzmem.c#L268 > Bartosz, I am thinking to remove below check in next rev like mentioned above. https://elixir.bootlin.com/linux/v6.12-rc3/source/drivers/firmware/qcom/qcom_tzmem.c#L268 Do you have any other opinion here? Please let me know.
On Tue, 22 Oct 2024 at 07:43, Kuldeep Singh <quic_kuldsing@quicinc.com> wrote: > > > > On 10/16/2024 2:31 PM, Kuldeep Singh wrote: > > > > On 10/14/2024 6:38 PM, Bartosz Golaszewski wrote: > >> On Mon, Oct 14, 2024 at 1:19 PM Kuldeep Singh <quic_kuldsing@quicinc.com> wrote: > >>> > >>> The qcom_tzmem driver currently has exposed APIs that lack validations > >>> on required input parameters. This oversight can lead to unexpected null > >>> pointer dereference crashes. > >>> > >> > >> The commit message is not true. None of the things you changed below > >> can lead to a NULL-pointer dereference.> > >>> To address this issue, add sanity for required input parameters. > >>> > >>> Signed-off-by: Kuldeep Singh <quic_kuldsing@quicinc.com> > >>> --- > >>> drivers/firmware/qcom/qcom_tzmem.c | 6 ++++++ > >>> 1 file changed, 6 insertions(+) > >>> > >>> diff --git a/drivers/firmware/qcom/qcom_tzmem.c b/drivers/firmware/qcom/qcom_tzmem.c > >>> index 92b365178235..977e48fec32f 100644 > >>> --- a/drivers/firmware/qcom/qcom_tzmem.c > >>> +++ b/drivers/firmware/qcom/qcom_tzmem.c > >>> @@ -203,6 +203,9 @@ qcom_tzmem_pool_new(const struct qcom_tzmem_pool_config *config) > >>> > >>> might_sleep(); > >>> > >>> + if (!config->policy) > >>> + return ERR_PTR(-EINVAL); > >> > >> This is already handled by the default case of the switch. > > > > Ack. Need to drop. > > https://elixir.bootlin.com/linux/v6.12-rc3/source/drivers/firmware/qcom/qcom_tzmem.c#L218 > > > > While examining qcom_tzmem_pool_free under the same principle, it > > appears the following check is unnecessary. > > https://elixir.bootlin.com/linux/v6.12-rc3/source/drivers/firmware/qcom/qcom_tzmem.c#L268 > > > > Bartosz, > I am thinking to remove below check in next rev like mentioned above. > https://elixir.bootlin.com/linux/v6.12-rc3/source/drivers/firmware/qcom/qcom_tzmem.c#L268 > > Do you have any other opinion here? > Please let me know. > No, let's keep the NULL-pointer check and add it to qcom_tzmem_free(), I'm not against it. I was just saying that in the latter case it will already be handled by the radix tree lookup. Bart
On 10/22/2024 12:27 PM, Bartosz Golaszewski wrote: > On Tue, 22 Oct 2024 at 07:43, Kuldeep Singh <quic_kuldsing@quicinc.com> wrote: >> >> >> >> On 10/16/2024 2:31 PM, Kuldeep Singh wrote: >>> >>> On 10/14/2024 6:38 PM, Bartosz Golaszewski wrote: >>>> On Mon, Oct 14, 2024 at 1:19 PM Kuldeep Singh <quic_kuldsing@quicinc.com> wrote: >>>>> >>>>> The qcom_tzmem driver currently has exposed APIs that lack validations >>>>> on required input parameters. This oversight can lead to unexpected null >>>>> pointer dereference crashes. >>>>> >>>> >>>> The commit message is not true. None of the things you changed below >>>> can lead to a NULL-pointer dereference.> >>>>> To address this issue, add sanity for required input parameters. >>>>> >>>>> Signed-off-by: Kuldeep Singh <quic_kuldsing@quicinc.com> >>>>> --- >>>>> drivers/firmware/qcom/qcom_tzmem.c | 6 ++++++ >>>>> 1 file changed, 6 insertions(+) >>>>> >>>>> diff --git a/drivers/firmware/qcom/qcom_tzmem.c b/drivers/firmware/qcom/qcom_tzmem.c >>>>> index 92b365178235..977e48fec32f 100644 >>>>> --- a/drivers/firmware/qcom/qcom_tzmem.c >>>>> +++ b/drivers/firmware/qcom/qcom_tzmem.c >>>>> @@ -203,6 +203,9 @@ qcom_tzmem_pool_new(const struct qcom_tzmem_pool_config *config) >>>>> >>>>> might_sleep(); >>>>> >>>>> + if (!config->policy) >>>>> + return ERR_PTR(-EINVAL); >>>> >>>> This is already handled by the default case of the switch. >>> >>> Ack. Need to drop. >>> https://elixir.bootlin.com/linux/v6.12-rc3/source/drivers/firmware/qcom/qcom_tzmem.c#L218 >>> >>> While examining qcom_tzmem_pool_free under the same principle, it >>> appears the following check is unnecessary. >>> https://elixir.bootlin.com/linux/v6.12-rc3/source/drivers/firmware/qcom/qcom_tzmem.c#L268 >>> >> >> Bartosz, >> I am thinking to remove below check in next rev like mentioned above. >> https://elixir.bootlin.com/linux/v6.12-rc3/source/drivers/firmware/qcom/qcom_tzmem.c#L268 >> >> Do you have any other opinion here? >> Please let me know. >> > > No, let's keep the NULL-pointer check and add it to qcom_tzmem_free(), > I'm not against it. I was just saying that in the latter case it will > already be handled by the radix tree lookup. Hey, I think you misread my comment. Let me explain more. As agreed, Will drop (!config->policy) check from qcom_tzmem_pool_new because it's already present. https://elixir.bootlin.com/linux/v6.12-rc3/source/drivers/firmware/qcom/qcom_tzmem.c#L218 Keep (!vaddr) check in qcom_tzmem_free as discussed above. https://elixir.bootlin.com/linux/v6.12-rc3/source/drivers/firmware/qcom/qcom_tzmem.c#L411 And last thing, like we don't check (!pool) in qcom_tzmem_alloc as it cannot be null, same way I believe (!pool) is unnecessary in qcom_tzmem_pool_free as qcom_tzmem_pool_new should return valid pool and if not, should be handled by calling driver. https://elixir.bootlin.com/linux/v6.12-rc3/source/drivers/firmware/qcom/qcom_tzmem.c#L369 https://elixir.bootlin.com/linux/v6.12-rc3/source/drivers/firmware/qcom/qcom_tzmem.c#L268
On Tue, Oct 22, 2024 at 8:34 PM Kuldeep Singh <quic_kuldsing@quicinc.com> wrote: > > > > On 10/22/2024 12:27 PM, Bartosz Golaszewski wrote: > > On Tue, 22 Oct 2024 at 07:43, Kuldeep Singh <quic_kuldsing@quicinc.com> wrote: > >> > >> > >> > >> On 10/16/2024 2:31 PM, Kuldeep Singh wrote: > >>> > >>> On 10/14/2024 6:38 PM, Bartosz Golaszewski wrote: > >>>> On Mon, Oct 14, 2024 at 1:19 PM Kuldeep Singh <quic_kuldsing@quicinc.com> wrote: > >>>>> > >>>>> The qcom_tzmem driver currently has exposed APIs that lack validations > >>>>> on required input parameters. This oversight can lead to unexpected null > >>>>> pointer dereference crashes. > >>>>> > >>>> > >>>> The commit message is not true. None of the things you changed below > >>>> can lead to a NULL-pointer dereference.> > >>>>> To address this issue, add sanity for required input parameters. > >>>>> > >>>>> Signed-off-by: Kuldeep Singh <quic_kuldsing@quicinc.com> > >>>>> --- > >>>>> drivers/firmware/qcom/qcom_tzmem.c | 6 ++++++ > >>>>> 1 file changed, 6 insertions(+) > >>>>> > >>>>> diff --git a/drivers/firmware/qcom/qcom_tzmem.c b/drivers/firmware/qcom/qcom_tzmem.c > >>>>> index 92b365178235..977e48fec32f 100644 > >>>>> --- a/drivers/firmware/qcom/qcom_tzmem.c > >>>>> +++ b/drivers/firmware/qcom/qcom_tzmem.c > >>>>> @@ -203,6 +203,9 @@ qcom_tzmem_pool_new(const struct qcom_tzmem_pool_config *config) > >>>>> > >>>>> might_sleep(); > >>>>> > >>>>> + if (!config->policy) > >>>>> + return ERR_PTR(-EINVAL); > >>>> > >>>> This is already handled by the default case of the switch. > >>> > >>> Ack. Need to drop. > >>> https://elixir.bootlin.com/linux/v6.12-rc3/source/drivers/firmware/qcom/qcom_tzmem.c#L218 > >>> > >>> While examining qcom_tzmem_pool_free under the same principle, it > >>> appears the following check is unnecessary. > >>> https://elixir.bootlin.com/linux/v6.12-rc3/source/drivers/firmware/qcom/qcom_tzmem.c#L268 > >>> > >> > >> Bartosz, > >> I am thinking to remove below check in next rev like mentioned above. > >> https://elixir.bootlin.com/linux/v6.12-rc3/source/drivers/firmware/qcom/qcom_tzmem.c#L268 > >> > >> Do you have any other opinion here? > >> Please let me know. > >> > > > > No, let's keep the NULL-pointer check and add it to qcom_tzmem_free(), > > I'm not against it. I was just saying that in the latter case it will > > already be handled by the radix tree lookup. > > Hey, I think you misread my comment. Let me explain more. > As agreed, Will drop (!config->policy) check from qcom_tzmem_pool_new > because it's already present. > https://elixir.bootlin.com/linux/v6.12-rc3/source/drivers/firmware/qcom/qcom_tzmem.c#L218 > > Keep (!vaddr) check in qcom_tzmem_free as discussed above. > https://elixir.bootlin.com/linux/v6.12-rc3/source/drivers/firmware/qcom/qcom_tzmem.c#L411 > > And last thing, like we don't check (!pool) in qcom_tzmem_alloc as it > cannot be null, same way I believe (!pool) is unnecessary in > qcom_tzmem_pool_free as qcom_tzmem_pool_new should return valid pool and > if not, should be handled by calling driver. > https://elixir.bootlin.com/linux/v6.12-rc3/source/drivers/firmware/qcom/qcom_tzmem.c#L369 > https://elixir.bootlin.com/linux/v6.12-rc3/source/drivers/firmware/qcom/qcom_tzmem.c#L268 > Well I would say this is just churn if it's already there but yeah it cannot be NULL so I won't object. Bart
diff --git a/drivers/firmware/qcom/qcom_tzmem.c b/drivers/firmware/qcom/qcom_tzmem.c index 92b365178235..977e48fec32f 100644 --- a/drivers/firmware/qcom/qcom_tzmem.c +++ b/drivers/firmware/qcom/qcom_tzmem.c @@ -203,6 +203,9 @@ qcom_tzmem_pool_new(const struct qcom_tzmem_pool_config *config) might_sleep(); + if (!config->policy) + return ERR_PTR(-EINVAL); + switch (config->policy) { case QCOM_TZMEM_POLICY_STATIC: if (!config->initial_size) @@ -412,6 +415,9 @@ void qcom_tzmem_free(void *vaddr) { struct qcom_tzmem_chunk *chunk; + if (!vaddr) + return; + scoped_guard(spinlock_irqsave, &qcom_tzmem_chunks_lock) chunk = radix_tree_delete_item(&qcom_tzmem_chunks, (unsigned long)vaddr, NULL);
The qcom_tzmem driver currently has exposed APIs that lack validations on required input parameters. This oversight can lead to unexpected null pointer dereference crashes. To address this issue, add sanity for required input parameters. Signed-off-by: Kuldeep Singh <quic_kuldsing@quicinc.com> --- drivers/firmware/qcom/qcom_tzmem.c | 6 ++++++ 1 file changed, 6 insertions(+)