Coverity: nv50_pior_atomic_enable(): Memory - corruptions

From: coverity-bot
Date: Thu Nov 10 2022 - 11:49:45 EST


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:

Wed Nov 9 08:22:02 2022 +1000
813443721331 ("drm/nouveau/disp: move DP link config into acquire")

Coverity reported the following:

*** CID 1527268: Memory - corruptions (OVERRUN)
drivers/gpu/drm/nouveau/dispnv50/disp.c:1817 in nv50_pior_atomic_enable()
1811 case DCB_OUTPUT_TMDS:
1812 ctrl |= NVDEF(NV507D, PIOR_SET_CONTROL, PROTOCOL, EXT_TMDS_ENC);
1813 nvif_outp_acquire_tmds(&nv_encoder->outp, false, false, 0, 0, 0, false);
1814 break;
1815 case DCB_OUTPUT_DP:
1816 ctrl |= NVDEF(NV507D, PIOR_SET_CONTROL, PROTOCOL, EXT_TMDS_ENC);
vvv CID 1527268: Memory - corruptions (OVERRUN)
vvv Overrunning array "(*nv_encoder).dp.dpcd" of 15 bytes by passing it to a function which accesses it at byte offset 15.
1817 nvif_outp_acquire_dp(&nv_encoder->outp, nv_encoder->dp.dpcd, 0, 0, false, false);
1818 break;
1819 default:
1820 BUG();
1821 break;
1822 }

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@xxxxxxxxxxxx>
Addresses-Coverity-ID: 1527268 ("Memory - corruptions")
Fixes: 813443721331 ("drm/nouveau/disp: move DP link config into acquire")

Thanks for your attention!

--
Coverity-bot