Subject: Coverity: submit_dmub_burst_write(): Memory - corruptions

From: coverity-bot <[email-masked]>
Date: Mon, 11 Nov 2019 17:35:56 -0800

Hello!

This is an experimental automated report about issues detected by Coverity
from a scan of next-20191108 as part of the linux-next weekly 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 recent commits:

c264644545d2 ("drm/amd/display: Add DMUB support to DC")

Coverity reported the following:

*** CID 1487839:  Memory - corruptions  (OVERRUN)
/drivers/gpu/drm/amd/display/dc/dc_helper.c: 76 in submit_dmub_burst_write()
70     	cmd_buf->header.payload_bytes =
71     			sizeof(uint32_t) * offload->reg_seq_count;
72
73     	gather = ctx->dmub_srv->reg_helper_offload.gather_in_progress;
74     	ctx->dmub_srv->reg_helper_offload.gather_in_progress = false;
75
vvv     CID 1487839:  Memory - corruptions  (OVERRUN)
vvv     Overrunning struct type dmub_cmd_header of 4 bytes by passing it to a function which accesses it at byte offset 63.
76     	dc_dmub_srv_cmd_queue(ctx->dmub_srv, &cmd_buf->header);
77
78     	ctx->dmub_srv->reg_helper_offload.gather_in_progress = gather;
79
80     	memset(cmd_buf, 0, sizeof(*cmd_buf));
81

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 <[email-masked]>
Addresses-Coverity-ID: 1487839 ("Memory - corruptions")
Fixes: c264644545d2 ("drm/amd/display: Add DMUB support to DC")

Thanks for your attention!

-- 
Coverity-bot