Commit 37454bcb authored by Justin Stitt's avatar Justin Stitt Committed by Lyude Paul
Browse files

drm/nouveau/pm: refactor deprecated strncpy 

`strncpy` is deprecated for use on NUL-terminated destination strings [1].

We should prefer more robust and less ambiguous string interfaces.

A suitable replacement is `strscpy` [2] due to the fact that it guarantees
NUL-termination on the destination buffer without unnecessarily NUL-padding.

Link: https://www.kernel.org/doc/html/latest/process/deprecated.html#strncpy-on-nul-terminated-strings [1]
Link: https://manpages.debian.org/testing/linux-manual-4.8/strscpy.9.en.html [2]
Link: https://github.com/KSPP/linux/issues/90


Cc: linux-hardening@vger.kernel.org
Signed-off-by: default avatarJustin Stitt <justinstitt@google.com>
Reviewed-by: default avatarKees Cook <keescook@chromium.org>
Reviewed-by: default avatarLyude Paul <lyude@redhat.com>
Signed-off-by: default avatarLyude Paul <lyude@redhat.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20230914-strncpy-drivers-gpu-drm-nouveau-nvkm-engine-pm-base-c-v1-1-4b09ed453f84@google.com
parent 00fb28fd

drivers/gpu/drm/nouveau/nvkm/engine/pm/base.c

+3 −4
Original line number Diff line number Diff line
@@ -462,7 +462,7 @@ nvkm_perfmon_mthd_query_domain(struct nvkm_perfmon *perfmon, 


		args->v0.id         = di;

		args->v0.signal_nr  = nvkm_perfdom_count_perfsig(dom);

		strncpy(args->v0.name, dom->name, sizeof(args->v0.name) - 1);

		strscpy(args->v0.name, dom->name, sizeof(args->v0.name));



		/* Currently only global counters (PCOUNTER) are implemented

		 * but this will be different for local counters (MP). */
@@ -513,8 +513,7 @@ nvkm_perfmon_mthd_query_signal(struct nvkm_perfmon *perfmon, 
			snprintf(args->v0.name, sizeof(args->v0.name),

				 "/%s/%02x", dom->name, si);

		} else {

			strncpy(args->v0.name, sig->name,

				sizeof(args->v0.name) - 1);

			strscpy(args->v0.name, sig->name, sizeof(args->v0.name));

		}



		args->v0.signal = si;
@@ -572,7 +571,7 @@ nvkm_perfmon_mthd_query_source(struct nvkm_perfmon *perfmon, 


		args->v0.source = sig->source[si];

		args->v0.mask   = src->mask;

		strncpy(args->v0.name, src->name, sizeof(args->v0.name) - 1);

		strscpy(args->v0.name, src->name, sizeof(args->v0.name));

	}



	if (++si < source_nr) {