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charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Fri, Dec 03, 2021 at 01:25:17AM -0800, Kees Cook wrote: > The link_status array was not large enough to read the Adjust Request > Post Cursor2 register. Adjust the size to include it. Found with a > -Warray-bounds build: >=20 > drivers/gpu/drm/drm_dp_helper.c: In function 'drm_dp_get_adjust_request_p= ost_cursor': > drivers/gpu/drm/drm_dp_helper.c:59:27: error: array subscript 10 is outsi= de array bounds of 'const u8[6]' {aka 'const unsigned char[6]'} [-Werror=3D= array-bounds] > 59 | return link_status[r - DP_LANE0_1_STATUS]; > | ~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~ > drivers/gpu/drm/drm_dp_helper.c:147:51: note: while referencing 'link_sta= tus' > 147 | u8 drm_dp_get_adjust_request_post_cursor(const u8 link_status[DP_= LINK_STATUS_SIZE], > | ~~~~~~~~~^~~~~~~~~~~~~~~= ~~~~~~~~~~~~~~~~~ >=20 > Fixes: 79465e0ffeb9 ("drm/dp: Add helper to get post-cursor adjustments") > Signed-off-by: Kees Cook > --- > v2: Fix missed array size change in intel_dp_check_mst_status() > --- > drivers/gpu/drm/i915/display/intel_dp.c | 8 ++++---- > include/drm/drm_dp_helper.h | 10 +++++++++- > 2 files changed, 13 insertions(+), 5 deletions(-) This sounds very familiar and I vaguely recall typing up a patch like that a long time ago. But I obviously failed because that never seems to have made it upstream. Or perhaps I'm misremembering and was thinking about this instead: https://chromium-review.googlesource.com/c/chromiumos/third_party/kernel/+= /338590/ Bonus points for adding that comment with background information on why we need this. Reviewed-by: Thierry Reding --VkIp7FKiDawaU8EY Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iQIzBAABCAAdFiEEiOrDCAFJzPfAjcif3SOs138+s6EFAmGqN7YACgkQ3SOs138+ s6Hupw//ezsxvTy2Xe2q0ZvKLa88BWT8aE7/CjGtbmoBZbo6/BPlvXAj2Ruuj51E S6XsQnWmS3OjmE2MXWrJPZcACH3So+VgJz4qyg0bMwy/S54a2QUTnl3bH7cGPnr/ ZMoeYFSceGlE25EkNffBnYwMwkNIu7jWjmFRESryDZRC86sIvLbPF1E46rmKyQjB sJh/GmmqBaVpuG1vgnoAdFT2o8KOsV2PqdkgMmnsXZzT7b2tiKXx3FkdLURQ4vdE UnzwT699ZtrYzzYn1b6XbKbEpTELu1kUSCabt9hTPLWB8GG7nbO/SH6tbDEuDpmt d237GVQBxZMMHHdpvriwn/4ATlY5e0KC+3QKlKfPH/vkJ4yyb7vO6f2GCvThHw3m cO/MRAeuJ0sNMT1nL/k+T5+0otMRZEhRJmNDLHYDMtxU0nEzSddXU/eSyYMpNLnX NIoB/9qUu9XFr1CfOhStWjpcqsa7DkYc2N3+ufHHzVe881XHvP1z4Jz94RgiI4MP fHZhk/uA85pzxIYHUOI+1kLT6s/QdKmowyIlxZSjXrNus2lkndK90lcbeX/lkTch VvEQH9XnCOnL4drimNYtuiBRi3LHodCVJj3493KzbklLfvXpc/ubEfBgu160xB3G 49urmt4HCSu1mnTUAs7Gs5PVzgxg8IxHMNkStutxmTKYLZBvE5g= =N22+ -----END PGP SIGNATURE----- --VkIp7FKiDawaU8EY-- From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id B56EEC4167B for ; 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charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Fri, Dec 03, 2021 at 01:25:17AM -0800, Kees Cook wrote: > The link_status array was not large enough to read the Adjust Request > Post Cursor2 register. Adjust the size to include it. Found with a > -Warray-bounds build: >=20 > drivers/gpu/drm/drm_dp_helper.c: In function 'drm_dp_get_adjust_request_p= ost_cursor': > drivers/gpu/drm/drm_dp_helper.c:59:27: error: array subscript 10 is outsi= de array bounds of 'const u8[6]' {aka 'const unsigned char[6]'} [-Werror=3D= array-bounds] > 59 | return link_status[r - DP_LANE0_1_STATUS]; > | ~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~ > drivers/gpu/drm/drm_dp_helper.c:147:51: note: while referencing 'link_sta= tus' > 147 | u8 drm_dp_get_adjust_request_post_cursor(const u8 link_status[DP_= LINK_STATUS_SIZE], > | ~~~~~~~~~^~~~~~~~~~~~~~~= ~~~~~~~~~~~~~~~~~ >=20 > Fixes: 79465e0ffeb9 ("drm/dp: Add helper to get post-cursor adjustments") > Signed-off-by: Kees Cook > --- > v2: Fix missed array size change in intel_dp_check_mst_status() > --- > drivers/gpu/drm/i915/display/intel_dp.c | 8 ++++---- > include/drm/drm_dp_helper.h | 10 +++++++++- > 2 files changed, 13 insertions(+), 5 deletions(-) This sounds very familiar and I vaguely recall typing up a patch like that a long time ago. But I obviously failed because that never seems to have made it upstream. Or perhaps I'm misremembering and was thinking about this instead: https://chromium-review.googlesource.com/c/chromiumos/third_party/kernel/+= /338590/ Bonus points for adding that comment with background information on why we need this. Reviewed-by: Thierry Reding --VkIp7FKiDawaU8EY Content-Type: application/pgp-signature; name="signature.asc" -----BEGIN PGP SIGNATURE----- iQIzBAABCAAdFiEEiOrDCAFJzPfAjcif3SOs138+s6EFAmGqN7YACgkQ3SOs138+ s6Hupw//ezsxvTy2Xe2q0ZvKLa88BWT8aE7/CjGtbmoBZbo6/BPlvXAj2Ruuj51E S6XsQnWmS3OjmE2MXWrJPZcACH3So+VgJz4qyg0bMwy/S54a2QUTnl3bH7cGPnr/ ZMoeYFSceGlE25EkNffBnYwMwkNIu7jWjmFRESryDZRC86sIvLbPF1E46rmKyQjB sJh/GmmqBaVpuG1vgnoAdFT2o8KOsV2PqdkgMmnsXZzT7b2tiKXx3FkdLURQ4vdE UnzwT699ZtrYzzYn1b6XbKbEpTELu1kUSCabt9hTPLWB8GG7nbO/SH6tbDEuDpmt d237GVQBxZMMHHdpvriwn/4ATlY5e0KC+3QKlKfPH/vkJ4yyb7vO6f2GCvThHw3m cO/MRAeuJ0sNMT1nL/k+T5+0otMRZEhRJmNDLHYDMtxU0nEzSddXU/eSyYMpNLnX NIoB/9qUu9XFr1CfOhStWjpcqsa7DkYc2N3+ufHHzVe881XHvP1z4Jz94RgiI4MP fHZhk/uA85pzxIYHUOI+1kLT6s/QdKmowyIlxZSjXrNus2lkndK90lcbeX/lkTch VvEQH9XnCOnL4drimNYtuiBRi3LHodCVJj3493KzbklLfvXpc/ubEfBgu160xB3G 49urmt4HCSu1mnTUAs7Gs5PVzgxg8IxHMNkStutxmTKYLZBvE5g= =N22+ -----END PGP SIGNATURE----- --VkIp7FKiDawaU8EY-- From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 05671C43217 for ; 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charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Fri, Dec 03, 2021 at 01:25:17AM -0800, Kees Cook wrote: > The link_status array was not large enough to read the Adjust Request > Post Cursor2 register. Adjust the size to include it. Found with a > -Warray-bounds build: >=20 > drivers/gpu/drm/drm_dp_helper.c: In function 'drm_dp_get_adjust_request_p= ost_cursor': > drivers/gpu/drm/drm_dp_helper.c:59:27: error: array subscript 10 is outsi= de array bounds of 'const u8[6]' {aka 'const unsigned char[6]'} [-Werror=3D= array-bounds] > 59 | return link_status[r - DP_LANE0_1_STATUS]; > | ~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~ > drivers/gpu/drm/drm_dp_helper.c:147:51: note: while referencing 'link_sta= tus' > 147 | u8 drm_dp_get_adjust_request_post_cursor(const u8 link_status[DP_= LINK_STATUS_SIZE], > | ~~~~~~~~~^~~~~~~~~~~~~~~= ~~~~~~~~~~~~~~~~~ >=20 > Fixes: 79465e0ffeb9 ("drm/dp: Add helper to get post-cursor adjustments") > Signed-off-by: Kees Cook > --- > v2: Fix missed array size change in intel_dp_check_mst_status() > --- > drivers/gpu/drm/i915/display/intel_dp.c | 8 ++++---- > include/drm/drm_dp_helper.h | 10 +++++++++- > 2 files changed, 13 insertions(+), 5 deletions(-) This sounds very familiar and I vaguely recall typing up a patch like that a long time ago. But I obviously failed because that never seems to have made it upstream. Or perhaps I'm misremembering and was thinking about this instead: https://chromium-review.googlesource.com/c/chromiumos/third_party/kernel/+= /338590/ Bonus points for adding that comment with background information on why we need this. 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