Jani Nikula
2022-Nov-11 09:13 UTC
[Nouveau] Coverity: nouveau_dp_irq(): Null pointer dereferences
On Thu, 10 Nov 2022, coverity-bot <keescook at chromium.org> wrote:> Hello! > > This is an experimental semi-automated report about issues detected by > Coverity from a scan of next-20221110 as part of the linux-next scan project: > https://scan.coverity.com/projects/linux-next-weekly-scan > > You're getting this email because you were associated with the identified > lines of code (noted below) that were touched by commits: > > Mon Aug 31 19:10:08 2020 -0400 > a0922278f83e ("drm/nouveau/kms/nv50-: Refactor and cleanup DP HPD handling")Hi Kees, this looks like a good idea, but maybe double check the Cc list generation? I was Cc'd on four mails today that I thought were irrelevant to me. Thanks, Jani.> > Coverity reported the following: > > *** CID 1527266: Null pointer dereferences (REVERSE_INULL) > drivers/gpu/drm/nouveau/nouveau_dp.c:237 in nouveau_dp_irq() > 231 struct nouveau_encoder *outp = find_encoder(connector, DCB_OUTPUT_DP); > 232 struct nouveau_drm *drm = nouveau_drm(outp->base.base.dev); > 233 struct nv50_mstm *mstm; > 234 u64 hpd = 0; > 235 int ret; > 236 > vvv CID 1527266: Null pointer dereferences (REVERSE_INULL) > vvv Null-checking "outp" suggests that it may be null, but it has already been dereferenced on all paths leading to the check. > 237 if (!outp) > 238 return; > 239 > 240 mstm = outp->dp.mstm; > 241 NV_DEBUG(drm, "service %s\n", connector->name); > 242 > > If this is a false positive, please let us know so we can mark it as > such, or teach the Coverity rules to be smarter. If not, please make > sure fixes get into linux-next. :) For patches fixing this, please > include these lines (but double-check the "Fixes" first): > > Reported-by: coverity-bot <keescook+coverity-bot at chromium.org> > Addresses-Coverity-ID: 1527266 ("Null pointer dereferences") > Fixes: a0922278f83e ("drm/nouveau/kms/nv50-: Refactor and cleanup DP HPD handling") > > Thanks for your attention!-- Jani Nikula, Intel Open Source Graphics Center
Kees Cook
2022-Nov-11 19:21 UTC
[Nouveau] Coverity: nouveau_dp_irq(): Null pointer dereferences
On Fri, Nov 11, 2022 at 11:13:17AM +0200, Jani Nikula wrote:> On Thu, 10 Nov 2022, coverity-bot <keescook at chromium.org> wrote: > > Hello! > > > > This is an experimental semi-automated report about issues detected by > > Coverity from a scan of next-20221110 as part of the linux-next scan project: > > https://scan.coverity.com/projects/linux-next-weekly-scan > > > > You're getting this email because you were associated with the identified > > lines of code (noted below) that were touched by commits: > > > > Mon Aug 31 19:10:08 2020 -0400 > > a0922278f83e ("drm/nouveau/kms/nv50-: Refactor and cleanup DP HPD handling") > > Hi Kees, this looks like a good idea, but maybe double check the Cc list > generation? I was Cc'd on four mails today that I thought were > irrelevant to me.Hi! Heh, I was recently asked to _expand_ the CC list. :) For these last pass of reports, I added a get_maintainers.pl run to the identified commit. In this instance, the commit touched: drivers/gpu/drm/nouveau/dispnv04/disp.c | 6 + drivers/gpu/drm/nouveau/dispnv50/disp.c | 192 ++++++++++++++++++++++-------------------------- drivers/gpu/drm/nouveau/nouveau_connector.c | 14 --- drivers/gpu/drm/nouveau/nouveau_display.c | 2 drivers/gpu/drm/nouveau/nouveau_display.h | 2 drivers/gpu/drm/nouveau/nouveau_dp.c | 132 ++++++++++++++++++++++++++++----- drivers/gpu/drm/nouveau/nouveau_encoder.h | 33 +++++++- 7 files changed, 244 insertions(+), 137 deletions(-) And the get_maintainers.pl rationale was: Ben Skeggs <bskeggs at redhat.com> (supporter:DRM DRIVER FOR NVIDIA GEFORCE/QUADRO GPUS,commit_signer:1/1=100%,commit_signer:6/16=38%,authored:4/16=25%,added_lines:23/124=19%,removed_lines:36/152=24%) Karol Herbst <kherbst at redhat.com> (supporter:DRM DRIVER FOR NVIDIA GEFORCE/QUADRO GPUS,commit_signer:2/1=100%) Lyude Paul <lyude at redhat.com> (supporter:DRM DRIVER FOR NVIDIA GEFORCE/QUADRO GPUS,commit_signer:9/16=56%,authored:6/16=38%,added_lines:92/124=74%,removed_lines:107/152=70%) David Airlie <airlied at gmail.com> (maintainer:DRM DRIVERS) Daniel Vetter <daniel at ffwll.ch> (maintainer:DRM DRIVERS) Ilia Mirkin <imirkin at alum.mit.edu> (commit_signer:1/1=100%,authored:1/1=100%,added_lines:2/2=100%,removed_lines:2/2=100%) "Nathan E. Egge" <unlord at xiph.org> (commit_signer:1/1=100%) Jani Nikula <jani.nikula at intel.com> (commit_signer:6/16=38%) Dave Airlie <airlied at redhat.com> (commit_signer:5/16=31%) Thomas Zimmermann <tzimmermann at suse.de> (commit_signer:4/16=25%,authored:4/16=25%) dri-devel at lists.freedesktop.org (open list:DRM DRIVER FOR NVIDIA GEFORCE/QUADRO GPUS) nouveau at lists.freedesktop.org (open list:DRM DRIVER FOR NVIDIA GEFORCE/QUADRO GPUS) -- Kees Cook