On Mon, Jun 09, 2025 at 04:59:37PM -0700, Josh Poimboeuf wrote:
> On Mon, Jun 09, 2025 at 05:20:53PM -0400, Joe Lawrence wrote:
> > If you touch sound/soc/sof/intel/, klp-build will error out with:
> >
> > Building patch module: livepatch-unCVE-2024-58012.ko
> > ERROR: modpost: module livepatch-unCVE-2024-58012 uses symbol
> > hda_dai_config from namespace SND_SOC_SOF_INTEL_HDA_COMMON, but does not
> > import it.
> > ERROR: modpost: module livepatch-unCVE-2024-58012 uses symbol
> > hdac_bus_eml_sdw_map_stream_ch from namespace SND_SOC_SOF_HDA_MLINK, but
> > does not import it.
> > make[2]: *** [scripts/Makefile.modpost:145:
> > /home/jolawren/src/centos-stream-10/klp-tmp/kmod/Module.symvers] Error 1
> > make[1]: *** [/home/jolawren/src/centos-stream-10/Makefile:1936: modpost]
> > Error 2
> > make: *** [Makefile:236: __sub-make] Error 2
> >
> > since the diff objects do not necessarily carry forward the namespace
> > import.
>
> Nice, thanks for finding that. I completely forgot about export
> namespaces.
>
> Can you send me the patch for testing? Is this the default centos10
> config?
>
Yeah, cs-10 sets CONFIG_NAMESPACES=y.
The hack I posted earlier abused modinfo to get the namespaces. You
could just dump the import_ns= strings in the .modinfo section with
readelf like (lightly tested):
diff --git a/scripts/livepatch/klp-build b/scripts/livepatch/klp-build
index f7d88726ed4f..671d1d07fd08 100755
--- a/scripts/livepatch/klp-build
+++ b/scripts/livepatch/klp-build
@@ -687,7 +687,9 @@ build_patch_module() {
cp -f "$SRC/scripts/livepatch/init.c" "$KMOD_DIR"
echo "obj-m := $NAME.o" > "$makefile"
- echo -n "$NAME-y := init.o" >> "$makefile"
+ echo -n "$NAME-y := init.o namespaces.o" >> "$makefile"
+
+ echo "#include <linux/module.h>" >> "$KMOD_DIR/namespaces.c"
find "$DIFF_DIR" -type f -name "*.o" | mapfile -t files
[[ ${#files[@]} -eq 0 ]] && die "no changes detected"
@@ -695,8 +697,16 @@ build_patch_module() {
for file in "${files[@]}"; do
local rel_file="${file#"$DIFF_DIR"/}"
local kmod_file="$KMOD_DIR/$rel_file"
+ local namespaces=()
local cmd_file
+ # Copy symbol namespace
+ readelf -p .modinfo "$ORIG_DIR/$rel_file" | \
+ gawk -F= '/\<import_ns=/ {print $2}' | mapfile -t
namespaces
+ for ns in "${namespaces[@]}"; do
+ echo "MODULE_IMPORT_NS(\"$ns\");" >>
"$KMOD_DIR/namespaces.c"
+ done
+
mkdir -p "$(dirname "$kmod_file")"
cp -f "$file" "$kmod_file"
