| Message ID | 20230922174951.work.160-kees@kernel.org (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | media: v4l2-event: Annotate struct v4l2_subscribed_event with __counted_by | expand |
On 9/22/23 11:49, Kees Cook wrote: > Prepare for the coming implementation by GCC and Clang of the __counted_by > attribute. Flexible array members annotated with __counted_by can have > their accesses bounds-checked at run-time checking via CONFIG_UBSAN_BOUNDS > (for array indexing) and CONFIG_FORTIFY_SOURCE (for strcpy/memcpy-family > functions). > > As found with Coccinelle[1], add __counted_by for struct v4l2_subscribed_event. > Additionally, since the element count member must be set before accessing > the annotated flexible array member, move its initialization earlier. > > [1] https://github.com/kees/kernel-tools/blob/trunk/coccinelle/examples/counted_by.cocci > > Cc: Mauro Carvalho Chehab <mchehab@kernel.org> > Cc: Hans Verkuil <hverkuil-cisco@xs4all.nl> > Cc: lijian <lijian@yulong.com> > Cc: linux-media@vger.kernel.org > Signed-off-by: Kees Cook <keescook@chromium.org> Reviewed-by: Gustavo A. R. Silva <gustavoars@kernel.org> Thanks
On Fri, 22 Sep 2023 10:49:52 -0700, Kees Cook wrote: > Prepare for the coming implementation by GCC and Clang of the __counted_by > attribute. Flexible array members annotated with __counted_by can have > their accesses bounds-checked at run-time checking via CONFIG_UBSAN_BOUNDS > (for array indexing) and CONFIG_FORTIFY_SOURCE (for strcpy/memcpy-family > functions). > > As found with Coccinelle[1], add __counted_by for struct v4l2_subscribed_event. > Additionally, since the element count member must be set before accessing > the annotated flexible array member, move its initialization earlier. > > [...] Since this is a trivial change and it's been 2 week without further discussion, I'll snag this patch. Applied to for-next/hardening, thanks! [1/1] media: v4l2-event: Annotate struct v4l2_subscribed_event with __counted_by https://git.kernel.org/kees/c/b1a20bbd4687 Take care,
On 06/10/2023 22:28, Kees Cook wrote: > On Fri, 22 Sep 2023 10:49:52 -0700, Kees Cook wrote: >> Prepare for the coming implementation by GCC and Clang of the __counted_by >> attribute. Flexible array members annotated with __counted_by can have >> their accesses bounds-checked at run-time checking via CONFIG_UBSAN_BOUNDS >> (for array indexing) and CONFIG_FORTIFY_SOURCE (for strcpy/memcpy-family >> functions). >> >> As found with Coccinelle[1], add __counted_by for struct v4l2_subscribed_event. >> Additionally, since the element count member must be set before accessing >> the annotated flexible array member, move its initialization earlier. >> >> [...] > > Since this is a trivial change and it's been 2 week without further > discussion, I'll snag this patch. Ah, I picked this up for media as well. Same for the other patch. You should have gotten an email from patchwork on Oct 3 that it was accepted. I think I should be more pro-active and reply when I pick up patches from non-media developers instead of relying on patchwork. It seems that it is easy to miss emails from patchwork. Regards, Hans > > Applied to for-next/hardening, thanks! > > [1/1] media: v4l2-event: Annotate struct v4l2_subscribed_event with __counted_by > https://git.kernel.org/kees/c/b1a20bbd4687 > > Take care, >
On Sat, Oct 07, 2023 at 11:21:26AM +0200, Hans Verkuil wrote: > On 06/10/2023 22:28, Kees Cook wrote: > > On Fri, 22 Sep 2023 10:49:52 -0700, Kees Cook wrote: > >> Prepare for the coming implementation by GCC and Clang of the __counted_by > >> attribute. Flexible array members annotated with __counted_by can have > >> their accesses bounds-checked at run-time checking via CONFIG_UBSAN_BOUNDS > >> (for array indexing) and CONFIG_FORTIFY_SOURCE (for strcpy/memcpy-family > >> functions). > >> > >> As found with Coccinelle[1], add __counted_by for struct v4l2_subscribed_event. > >> Additionally, since the element count member must be set before accessing > >> the annotated flexible array member, move its initialization earlier. > >> > >> [...] > > > > Since this is a trivial change and it's been 2 week without further > > discussion, I'll snag this patch. > > Ah, I picked this up for media as well. Same for the other patch. > You should have gotten an email from patchwork on Oct 3 that it was accepted. > > I think I should be more pro-active and reply when I pick up patches from > non-media developers instead of relying on patchwork. It seems that it is > easy to miss emails from patchwork. Ah! Thanks for reminding me. I'll drop them from the hardening tree. :) -Kees
diff --git a/drivers/media/v4l2-core/v4l2-event.c b/drivers/media/v4l2-core/v4l2-event.c index c5ce9f11ad7b..3898ff7edddb 100644 --- a/drivers/media/v4l2-core/v4l2-event.c +++ b/drivers/media/v4l2-core/v4l2-event.c @@ -238,6 +238,7 @@ int v4l2_event_subscribe(struct v4l2_fh *fh, sev = kvzalloc(struct_size(sev, events, elems), GFP_KERNEL); if (!sev) return -ENOMEM; + sev->elems = elems; for (i = 0; i < elems; i++) sev->events[i].sev = sev; sev->type = sub->type; @@ -245,7 +246,6 @@ int v4l2_event_subscribe(struct v4l2_fh *fh, sev->flags = sub->flags; sev->fh = fh; sev->ops = ops; - sev->elems = elems; mutex_lock(&fh->subscribe_lock); diff --git a/include/media/v4l2-event.h b/include/media/v4l2-event.h index 4ffa914ade3a..3a0e2588361c 100644 --- a/include/media/v4l2-event.h +++ b/include/media/v4l2-event.h @@ -78,7 +78,7 @@ struct v4l2_subscribed_event { unsigned int elems; unsigned int first; unsigned int in_use; - struct v4l2_kevent events[]; + struct v4l2_kevent events[] __counted_by(elems); }; /**
Prepare for the coming implementation by GCC and Clang of the __counted_by attribute. Flexible array members annotated with __counted_by can have their accesses bounds-checked at run-time checking via CONFIG_UBSAN_BOUNDS (for array indexing) and CONFIG_FORTIFY_SOURCE (for strcpy/memcpy-family functions). As found with Coccinelle[1], add __counted_by for struct v4l2_subscribed_event. Additionally, since the element count member must be set before accessing the annotated flexible array member, move its initialization earlier. [1] https://github.com/kees/kernel-tools/blob/trunk/coccinelle/examples/counted_by.cocci Cc: Mauro Carvalho Chehab <mchehab@kernel.org> Cc: Hans Verkuil <hverkuil-cisco@xs4all.nl> Cc: lijian <lijian@yulong.com> Cc: linux-media@vger.kernel.org Signed-off-by: Kees Cook <keescook@chromium.org> --- drivers/media/v4l2-core/v4l2-event.c | 2 +- include/media/v4l2-event.h | 2 +- 2 files changed, 2 insertions(+), 2 deletions(-)