| Message ID | 20230413200349.3492571-1-lucas.demarchi@intel.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | drm/i915/gt: Avoid out-of-bounds access when loading HuC | expand |
On 4/13/2023 1:03 PM, Lucas De Marchi wrote: > When HuC is loaded by GSC, there is no header definition for the kernel > to look at and firmware is just handed to GSC. However when reading the > version, it should still check the size of the blob to guarantee it's not > incurring into out-of-bounds array access. > > If firmware is smaller than expected, the following message is now > printed: > > # echo boom > /lib/firmware/i915/dg2_huc_gsc.bin > # dmesg | grep -i huc > [drm] GT0: HuC firmware i915/dg2_huc_gsc.bin: invalid size: 5 < 184 > [drm] *ERROR* GT0: HuC firmware i915/dg2_huc_gsc.bin: fetch failed -ENODATA > ... > > Even without this change the size, header and signature are still > checked by GSC when loading, so this only avoids the out-of-bounds array > access. > > Fixes: a7b516bd981f ("drm/i915/huc: Add fetch support for gsc-loaded HuC binary") > Cc: Daniele Ceraolo Spurio <daniele.ceraolospurio@intel.com> > Cc: Alan Previn <alan.previn.teres.alexis@intel.com> > Signed-off-by: Lucas De Marchi <lucas.demarchi@intel.com> Reviewed-by: Daniele Ceraolo Spurio <daniele.ceraolospurio@intel.com> Daniele > --- > drivers/gpu/drm/i915/gt/uc/intel_uc_fw.c | 21 +++++++++++++++++---- > 1 file changed, 17 insertions(+), 4 deletions(-) > > diff --git a/drivers/gpu/drm/i915/gt/uc/intel_uc_fw.c b/drivers/gpu/drm/i915/gt/uc/intel_uc_fw.c > index 1ac6f9f340e3..a82a53dbbc86 100644 > --- a/drivers/gpu/drm/i915/gt/uc/intel_uc_fw.c > +++ b/drivers/gpu/drm/i915/gt/uc/intel_uc_fw.c > @@ -489,12 +489,25 @@ static void __force_fw_fetch_failures(struct intel_uc_fw *uc_fw, int e) > } > } > > -static int check_gsc_manifest(const struct firmware *fw, > +static int check_gsc_manifest(struct intel_gt *gt, > + const struct firmware *fw, > struct intel_uc_fw *uc_fw) > { > u32 *dw = (u32 *)fw->data; > - u32 version_hi = dw[HUC_GSC_VERSION_HI_DW]; > - u32 version_lo = dw[HUC_GSC_VERSION_LO_DW]; > + u32 version_hi, version_lo; > + size_t min_size; > + > + /* Check the size of the blob before examining buffer contents */ > + min_size = sizeof(u32) * (HUC_GSC_VERSION_LO_DW + 1); > + if (unlikely(fw->size < min_size)) { > + gt_warn(gt, "%s firmware %s: invalid size: %zu < %zu\n", > + intel_uc_fw_type_repr(uc_fw->type), uc_fw->file_selected.path, > + fw->size, min_size); > + return -ENODATA; > + } > + > + version_hi = dw[HUC_GSC_VERSION_HI_DW]; > + version_lo = dw[HUC_GSC_VERSION_LO_DW]; > > uc_fw->file_selected.ver.major = FIELD_GET(HUC_GSC_MAJOR_VER_HI_MASK, version_hi); > uc_fw->file_selected.ver.minor = FIELD_GET(HUC_GSC_MINOR_VER_HI_MASK, version_hi); > @@ -665,7 +678,7 @@ static int check_fw_header(struct intel_gt *gt, > return 0; > > if (uc_fw->loaded_via_gsc) > - err = check_gsc_manifest(fw, uc_fw); > + err = check_gsc_manifest(gt, fw, uc_fw); > else > err = check_ccs_header(gt, fw, uc_fw); > if (err)
diff --git a/drivers/gpu/drm/i915/gt/uc/intel_uc_fw.c b/drivers/gpu/drm/i915/gt/uc/intel_uc_fw.c index 1ac6f9f340e3..a82a53dbbc86 100644 --- a/drivers/gpu/drm/i915/gt/uc/intel_uc_fw.c +++ b/drivers/gpu/drm/i915/gt/uc/intel_uc_fw.c @@ -489,12 +489,25 @@ static void __force_fw_fetch_failures(struct intel_uc_fw *uc_fw, int e) } } -static int check_gsc_manifest(const struct firmware *fw, +static int check_gsc_manifest(struct intel_gt *gt, + const struct firmware *fw, struct intel_uc_fw *uc_fw) { u32 *dw = (u32 *)fw->data; - u32 version_hi = dw[HUC_GSC_VERSION_HI_DW]; - u32 version_lo = dw[HUC_GSC_VERSION_LO_DW]; + u32 version_hi, version_lo; + size_t min_size; + + /* Check the size of the blob before examining buffer contents */ + min_size = sizeof(u32) * (HUC_GSC_VERSION_LO_DW + 1); + if (unlikely(fw->size < min_size)) { + gt_warn(gt, "%s firmware %s: invalid size: %zu < %zu\n", + intel_uc_fw_type_repr(uc_fw->type), uc_fw->file_selected.path, + fw->size, min_size); + return -ENODATA; + } + + version_hi = dw[HUC_GSC_VERSION_HI_DW]; + version_lo = dw[HUC_GSC_VERSION_LO_DW]; uc_fw->file_selected.ver.major = FIELD_GET(HUC_GSC_MAJOR_VER_HI_MASK, version_hi); uc_fw->file_selected.ver.minor = FIELD_GET(HUC_GSC_MINOR_VER_HI_MASK, version_hi); @@ -665,7 +678,7 @@ static int check_fw_header(struct intel_gt *gt, return 0; if (uc_fw->loaded_via_gsc) - err = check_gsc_manifest(fw, uc_fw); + err = check_gsc_manifest(gt, fw, uc_fw); else err = check_ccs_header(gt, fw, uc_fw); if (err)
When HuC is loaded by GSC, there is no header definition for the kernel to look at and firmware is just handed to GSC. However when reading the version, it should still check the size of the blob to guarantee it's not incurring into out-of-bounds array access. If firmware is smaller than expected, the following message is now printed: # echo boom > /lib/firmware/i915/dg2_huc_gsc.bin # dmesg | grep -i huc [drm] GT0: HuC firmware i915/dg2_huc_gsc.bin: invalid size: 5 < 184 [drm] *ERROR* GT0: HuC firmware i915/dg2_huc_gsc.bin: fetch failed -ENODATA ... Even without this change the size, header and signature are still checked by GSC when loading, so this only avoids the out-of-bounds array access. Fixes: a7b516bd981f ("drm/i915/huc: Add fetch support for gsc-loaded HuC binary") Cc: Daniele Ceraolo Spurio <daniele.ceraolospurio@intel.com> Cc: Alan Previn <alan.previn.teres.alexis@intel.com> Signed-off-by: Lucas De Marchi <lucas.demarchi@intel.com> --- drivers/gpu/drm/i915/gt/uc/intel_uc_fw.c | 21 +++++++++++++++++---- 1 file changed, 17 insertions(+), 4 deletions(-)