| Message ID | 20180313162411.GA1983@embeddedgus (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On Tue, Mar 13, 2018 at 11:24:11AM -0500, Gustavo A. R. Silva wrote: > In preparation to enabling -Wvla, remove VLA. In this particular > case directly use macro NVKM_MSGQUEUE_CMDLINE_SIZE instead of local > variable cmdline_size. Also, remove cmdline_size as it is not > actually useful anymore. > > The use of stack Variable Length Arrays needs to be avoided, as they > can be a vector for stack exhaustion, which can be both a runtime bug > or a security flaw. Also, in general, as code evolves it is easy to > lose track of how big a VLA can get. Thus, we can end up having runtime > failures that are hard to debug. > > Also, fixed as part of the directive to remove all VLAs from > the kernel: https://lkml.org/lkml/2018/3/7/621 > > Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com> > --- > Changes in v2: > - Use sizeof(buf) instead of NVKM_MSGQUEUE_CMDLINE_SIZE. This change > is based on the feedback provided by David Laight. Thanks David. > > drivers/gpu/drm/nouveau/nvkm/subdev/secboot/ls_ucode_msgqueue.c | 7 +++---- > 1 file changed, 3 insertions(+), 4 deletions(-) Reviewed-by: Thierry Reding <treding@nvidia.com>
On 14 March 2018 at 21:08, Thierry Reding <thierry.reding@gmail.com> wrote: > On Tue, Mar 13, 2018 at 11:24:11AM -0500, Gustavo A. R. Silva wrote: >> In preparation to enabling -Wvla, remove VLA. In this particular >> case directly use macro NVKM_MSGQUEUE_CMDLINE_SIZE instead of local >> variable cmdline_size. Also, remove cmdline_size as it is not >> actually useful anymore. >> >> The use of stack Variable Length Arrays needs to be avoided, as they >> can be a vector for stack exhaustion, which can be both a runtime bug >> or a security flaw. Also, in general, as code evolves it is easy to >> lose track of how big a VLA can get. Thus, we can end up having runtime >> failures that are hard to debug. >> >> Also, fixed as part of the directive to remove all VLAs from >> the kernel: https://lkml.org/lkml/2018/3/7/621 >> >> Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com> >> --- >> Changes in v2: >> - Use sizeof(buf) instead of NVKM_MSGQUEUE_CMDLINE_SIZE. This change >> is based on the feedback provided by David Laight. Thanks David. >> >> drivers/gpu/drm/nouveau/nvkm/subdev/secboot/ls_ucode_msgqueue.c | 7 +++---- >> 1 file changed, 3 insertions(+), 4 deletions(-) > > Reviewed-by: Thierry Reding <treding@nvidia.com> Thanks everyone. I've taken the patch in my tree. Ben. > > _______________________________________________ > dri-devel mailing list > dri-devel@lists.freedesktop.org > https://lists.freedesktop.org/mailman/listinfo/dri-devel >
On Thu, Mar 15, 2018 at 7:05 PM, Ben Skeggs <skeggsb@gmail.com> wrote: > On 14 March 2018 at 21:08, Thierry Reding <thierry.reding@gmail.com> wrote: >> On Tue, Mar 13, 2018 at 11:24:11AM -0500, Gustavo A. R. Silva wrote: >>> In preparation to enabling -Wvla, remove VLA. In this particular >>> case directly use macro NVKM_MSGQUEUE_CMDLINE_SIZE instead of local >>> variable cmdline_size. Also, remove cmdline_size as it is not >>> actually useful anymore. >>> >>> The use of stack Variable Length Arrays needs to be avoided, as they >>> can be a vector for stack exhaustion, which can be both a runtime bug >>> or a security flaw. Also, in general, as code evolves it is easy to >>> lose track of how big a VLA can get. Thus, we can end up having runtime >>> failures that are hard to debug. >>> >>> Also, fixed as part of the directive to remove all VLAs from >>> the kernel: https://lkml.org/lkml/2018/3/7/621 >>> >>> Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com> >>> --- >>> Changes in v2: >>> - Use sizeof(buf) instead of NVKM_MSGQUEUE_CMDLINE_SIZE. This change >>> is based on the feedback provided by David Laight. Thanks David. >>> >>> drivers/gpu/drm/nouveau/nvkm/subdev/secboot/ls_ucode_msgqueue.c | 7 +++---- >>> 1 file changed, 3 insertions(+), 4 deletions(-) >> >> Reviewed-by: Thierry Reding <treding@nvidia.com> > Thanks everyone. I've taken the patch in my tree. Hi! Just checking in on this -- I don't see this patch in linux-next. Is this queued somewhere else? Thanks! -Kees
On Thu, Apr 26, 2018 at 4:25 PM, Kees Cook <keescook@chromium.org> wrote: > On Thu, Mar 15, 2018 at 7:05 PM, Ben Skeggs <skeggsb@gmail.com> wrote: >> On 14 March 2018 at 21:08, Thierry Reding <thierry.reding@gmail.com> wrote: >>> On Tue, Mar 13, 2018 at 11:24:11AM -0500, Gustavo A. R. Silva wrote: >>>> In preparation to enabling -Wvla, remove VLA. In this particular >>>> case directly use macro NVKM_MSGQUEUE_CMDLINE_SIZE instead of local >>>> variable cmdline_size. Also, remove cmdline_size as it is not >>>> actually useful anymore. >>>> >>>> The use of stack Variable Length Arrays needs to be avoided, as they >>>> can be a vector for stack exhaustion, which can be both a runtime bug >>>> or a security flaw. Also, in general, as code evolves it is easy to >>>> lose track of how big a VLA can get. Thus, we can end up having runtime >>>> failures that are hard to debug. >>>> >>>> Also, fixed as part of the directive to remove all VLAs from >>>> the kernel: https://lkml.org/lkml/2018/3/7/621 >>>> >>>> Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com> >>>> --- >>>> Changes in v2: >>>> - Use sizeof(buf) instead of NVKM_MSGQUEUE_CMDLINE_SIZE. This change >>>> is based on the feedback provided by David Laight. Thanks David. >>>> >>>> drivers/gpu/drm/nouveau/nvkm/subdev/secboot/ls_ucode_msgqueue.c | 7 +++---- >>>> 1 file changed, 3 insertions(+), 4 deletions(-) >>> >>> Reviewed-by: Thierry Reding <treding@nvidia.com> >> Thanks everyone. I've taken the patch in my tree. > > Hi! > > Just checking in on this -- I don't see this patch in linux-next. Is > this queued somewhere else? Hi, it's been another month; I still don't see this in linux-next. Daniel, can this go via drm-misc? -Kees
On Thu, May 24, 2018 at 8:48 AM, Kees Cook <keescook@chromium.org> wrote: > On Thu, Apr 26, 2018 at 4:25 PM, Kees Cook <keescook@chromium.org> wrote: >> On Thu, Mar 15, 2018 at 7:05 PM, Ben Skeggs <skeggsb@gmail.com> wrote: >>> On 14 March 2018 at 21:08, Thierry Reding <thierry.reding@gmail.com> wrote: >>>> On Tue, Mar 13, 2018 at 11:24:11AM -0500, Gustavo A. R. Silva wrote: >>>>> In preparation to enabling -Wvla, remove VLA. In this particular >>>>> case directly use macro NVKM_MSGQUEUE_CMDLINE_SIZE instead of local >>>>> variable cmdline_size. Also, remove cmdline_size as it is not >>>>> actually useful anymore. >>>>> >>>>> The use of stack Variable Length Arrays needs to be avoided, as they >>>>> can be a vector for stack exhaustion, which can be both a runtime bug >>>>> or a security flaw. Also, in general, as code evolves it is easy to >>>>> lose track of how big a VLA can get. Thus, we can end up having runtime >>>>> failures that are hard to debug. >>>>> >>>>> Also, fixed as part of the directive to remove all VLAs from >>>>> the kernel: https://lkml.org/lkml/2018/3/7/621 >>>>> >>>>> Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com> >>>>> --- >>>>> Changes in v2: >>>>> - Use sizeof(buf) instead of NVKM_MSGQUEUE_CMDLINE_SIZE. This change >>>>> is based on the feedback provided by David Laight. Thanks David. >>>>> >>>>> drivers/gpu/drm/nouveau/nvkm/subdev/secboot/ls_ucode_msgqueue.c | 7 +++---- >>>>> 1 file changed, 3 insertions(+), 4 deletions(-) >>>> >>>> Reviewed-by: Thierry Reding <treding@nvidia.com> >>> Thanks everyone. I've taken the patch in my tree. >> >> Hi! >> >> Just checking in on this -- I don't see this patch in linux-next. Is >> this queued somewhere else? > > Hi, it's been another month; I still don't see this in linux-next. > Daniel, can this go via drm-misc? It's already queued in drm-next. > > -Kees > > -- > Kees Cook > Pixel Security
On Wed, May 23, 2018 at 5:36 PM, Ben Skeggs <bskeggs@redhat.com> wrote: > On Thu, May 24, 2018 at 8:48 AM, Kees Cook <keescook@chromium.org> wrote: >> On Thu, Apr 26, 2018 at 4:25 PM, Kees Cook <keescook@chromium.org> wrote: >>> On Thu, Mar 15, 2018 at 7:05 PM, Ben Skeggs <skeggsb@gmail.com> wrote: >>>> On 14 March 2018 at 21:08, Thierry Reding <thierry.reding@gmail.com> wrote: >>>>> On Tue, Mar 13, 2018 at 11:24:11AM -0500, Gustavo A. R. Silva wrote: >>>>>> In preparation to enabling -Wvla, remove VLA. In this particular >>>>>> case directly use macro NVKM_MSGQUEUE_CMDLINE_SIZE instead of local >>>>>> variable cmdline_size. Also, remove cmdline_size as it is not >>>>>> actually useful anymore. >>>>>> >>>>>> The use of stack Variable Length Arrays needs to be avoided, as they >>>>>> can be a vector for stack exhaustion, which can be both a runtime bug >>>>>> or a security flaw. Also, in general, as code evolves it is easy to >>>>>> lose track of how big a VLA can get. Thus, we can end up having runtime >>>>>> failures that are hard to debug. >>>>>> >>>>>> Also, fixed as part of the directive to remove all VLAs from >>>>>> the kernel: https://lkml.org/lkml/2018/3/7/621 >>>>>> >>>>>> Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com> >>>>>> --- >>>>>> Changes in v2: >>>>>> - Use sizeof(buf) instead of NVKM_MSGQUEUE_CMDLINE_SIZE. This change >>>>>> is based on the feedback provided by David Laight. Thanks David. >>>>>> >>>>>> drivers/gpu/drm/nouveau/nvkm/subdev/secboot/ls_ucode_msgqueue.c | 7 +++---- >>>>>> 1 file changed, 3 insertions(+), 4 deletions(-) >>>>> >>>>> Reviewed-by: Thierry Reding <treding@nvidia.com> >>>> Thanks everyone. I've taken the patch in my tree. >>> >>> Hi! >>> >>> Just checking in on this -- I don't see this patch in linux-next. Is >>> this queued somewhere else? >> >> Hi, it's been another month; I still don't see this in linux-next. >> Daniel, can this go via drm-misc? > It's already queued in drm-next. Ah-ha, great, thanks! Looks like I just got unlucky with linux-next pausing on the 17th and this getting committed on the 18th. :) But, yes, I see it now: https://cgit.freedesktop.org/drm/drm/commit/drivers/gpu/drm/nouveau/nvkm/subdev/secboot/ls_ucode_msgqueue.c?id=7bf5b70befd7817b9e42acbd2291b2042ea1bf81 -Kees
diff --git a/drivers/gpu/drm/nouveau/nvkm/subdev/secboot/ls_ucode_msgqueue.c b/drivers/gpu/drm/nouveau/nvkm/subdev/secboot/ls_ucode_msgqueue.c index 6f10b09..1e1f1c6 100644 --- a/drivers/gpu/drm/nouveau/nvkm/subdev/secboot/ls_ucode_msgqueue.c +++ b/drivers/gpu/drm/nouveau/nvkm/subdev/secboot/ls_ucode_msgqueue.c @@ -80,12 +80,11 @@ acr_ls_msgqueue_post_run(struct nvkm_msgqueue *queue, struct nvkm_falcon *falcon, u32 addr_args) { struct nvkm_device *device = falcon->owner->device; - u32 cmdline_size = NVKM_MSGQUEUE_CMDLINE_SIZE; - u8 buf[cmdline_size]; + u8 buf[NVKM_MSGQUEUE_CMDLINE_SIZE]; - memset(buf, 0, cmdline_size); + memset(buf, 0, sizeof(buf)); nvkm_msgqueue_write_cmdline(queue, buf); - nvkm_falcon_load_dmem(falcon, buf, addr_args, cmdline_size, 0); + nvkm_falcon_load_dmem(falcon, buf, addr_args, sizeof(buf), 0); /* rearm the queue so it will wait for the init message */ nvkm_msgqueue_reinit(queue);
In preparation to enabling -Wvla, remove VLA. In this particular case directly use macro NVKM_MSGQUEUE_CMDLINE_SIZE instead of local variable cmdline_size. Also, remove cmdline_size as it is not actually useful anymore. The use of stack Variable Length Arrays needs to be avoided, as they can be a vector for stack exhaustion, which can be both a runtime bug or a security flaw. Also, in general, as code evolves it is easy to lose track of how big a VLA can get. Thus, we can end up having runtime failures that are hard to debug. Also, fixed as part of the directive to remove all VLAs from the kernel: https://lkml.org/lkml/2018/3/7/621 Signed-off-by: Gustavo A. R. Silva <gustavo@embeddedor.com> --- Changes in v2: - Use sizeof(buf) instead of NVKM_MSGQUEUE_CMDLINE_SIZE. This change is based on the feedback provided by David Laight. Thanks David. drivers/gpu/drm/nouveau/nvkm/subdev/secboot/ls_ucode_msgqueue.c | 7 +++---- 1 file changed, 3 insertions(+), 4 deletions(-)