| Message ID | 20210111210528.734483-1-jcline@redhat.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
| Series | [v2] drm/amdkfd: Fix out-of-bounds read in kdf_create_vcrat_image_cpu() | expand |
Am 2021-01-11 um 4:05 p.m. schrieb Jeremy Cline: > KASAN reported a slab-out-of-bounds read of size 1 in > kdf_create_vcrat_image_cpu(). > > This occurs when, for example, when on an x86_64 with a single NUMA node > because kfd_fill_iolink_info_for_cpu() is a no-op, but afterwards the > sub_type_hdr->length, which is out-of-bounds, is read and multiplied by > entries. Fortunately, entries is 0 in this case so the overall > crat_table->length is still correct. > > Check if there were any entries before de-referencing sub_type_hdr which > may be pointing to out-of-bounds memory. > > Fixes: b7b6c38529c9 ("drm/amdkfd: Calculate CPU VCRAT size dynamically (v2)") > Suggested-by: Felix Kuehling <Felix.Kuehling@amd.com> > Signed-off-by: Jeremy Cline <jcline@redhat.com> Thanks. I'll apply this patch. Reviewed-by: Felix Kuehling <Felix.Kuehling@amd.com> > --- > drivers/gpu/drm/amd/amdkfd/kfd_crat.c | 11 +++++++---- > 1 file changed, 7 insertions(+), 4 deletions(-) > > diff --git a/drivers/gpu/drm/amd/amdkfd/kfd_crat.c b/drivers/gpu/drm/amd/amdkfd/kfd_crat.c > index 8cac497c2c45..a5640a6138cf 100644 > --- a/drivers/gpu/drm/amd/amdkfd/kfd_crat.c > +++ b/drivers/gpu/drm/amd/amdkfd/kfd_crat.c > @@ -1040,11 +1040,14 @@ static int kfd_create_vcrat_image_cpu(void *pcrat_image, size_t *size) > (struct crat_subtype_iolink *)sub_type_hdr); > if (ret < 0) > return ret; > - crat_table->length += (sub_type_hdr->length * entries); > - crat_table->total_entries += entries; > > - sub_type_hdr = (typeof(sub_type_hdr))((char *)sub_type_hdr + > - sub_type_hdr->length * entries); > + if (entries) { > + crat_table->length += (sub_type_hdr->length * entries); > + crat_table->total_entries += entries; > + > + sub_type_hdr = (typeof(sub_type_hdr))((char *)sub_type_hdr + > + sub_type_hdr->length * entries); > + } > #else > pr_info("IO link not available for non x86 platforms\n"); > #endif
diff --git a/drivers/gpu/drm/amd/amdkfd/kfd_crat.c b/drivers/gpu/drm/amd/amdkfd/kfd_crat.c index 8cac497c2c45..a5640a6138cf 100644 --- a/drivers/gpu/drm/amd/amdkfd/kfd_crat.c +++ b/drivers/gpu/drm/amd/amdkfd/kfd_crat.c @@ -1040,11 +1040,14 @@ static int kfd_create_vcrat_image_cpu(void *pcrat_image, size_t *size) (struct crat_subtype_iolink *)sub_type_hdr); if (ret < 0) return ret; - crat_table->length += (sub_type_hdr->length * entries); - crat_table->total_entries += entries; - sub_type_hdr = (typeof(sub_type_hdr))((char *)sub_type_hdr + - sub_type_hdr->length * entries); + if (entries) { + crat_table->length += (sub_type_hdr->length * entries); + crat_table->total_entries += entries; + + sub_type_hdr = (typeof(sub_type_hdr))((char *)sub_type_hdr + + sub_type_hdr->length * entries); + } #else pr_info("IO link not available for non x86 platforms\n"); #endif
KASAN reported a slab-out-of-bounds read of size 1 in kdf_create_vcrat_image_cpu(). This occurs when, for example, when on an x86_64 with a single NUMA node because kfd_fill_iolink_info_for_cpu() is a no-op, but afterwards the sub_type_hdr->length, which is out-of-bounds, is read and multiplied by entries. Fortunately, entries is 0 in this case so the overall crat_table->length is still correct. Check if there were any entries before de-referencing sub_type_hdr which may be pointing to out-of-bounds memory. Fixes: b7b6c38529c9 ("drm/amdkfd: Calculate CPU VCRAT size dynamically (v2)") Suggested-by: Felix Kuehling <Felix.Kuehling@amd.com> Signed-off-by: Jeremy Cline <jcline@redhat.com> --- drivers/gpu/drm/amd/amdkfd/kfd_crat.c | 11 +++++++---- 1 file changed, 7 insertions(+), 4 deletions(-)