On Sun, 6 Feb 2022 at 09:38, Michael S. Tsirkin <m...@redhat.com> wrote: > > From: Eric DeVolder <eric.devol...@oracle.com> > > This implements a PCI device for ACPI ERST. This implements the > non-NVRAM "mode" of operation for ERST as it is supported by > Linux and Windows. > > Signed-off-by: Eric DeVolder <eric.devol...@oracle.com> > Reviewed-by: Ani Sinha <a...@anisinha.ca> > Message-Id: <1643402289-22216-6-git-send-email-eric.devol...@oracle.com> > Reviewed-by: Michael S. Tsirkin <m...@redhat.com> > Signed-off-by: Michael S. Tsirkin <m...@redhat.com> > ---
Hi; Coverity points out a bug in this function (CID 1487125): > +static void check_erst_backend_storage(ERSTDeviceState *s, Error **errp) > +{ > + ERSTStorageHeader *header; > + uint32_t record_size; > + > + header = memory_region_get_ram_ptr(s->hostmem_mr); > + s->header = header; > + > + /* Ensure pointer to header is 64-bit aligned */ > + g_assert(QEMU_PTR_IS_ALIGNED(header, sizeof(uint64_t))); > + > + /* > + * Check if header is uninitialized; HostMemoryBackend inits to 0 > + */ > + if (le64_to_cpu(header->magic) == 0UL) { > + make_erst_storage_header(s); > + } > + > + /* Validity check record_size */ > + record_size = le32_to_cpu(header->record_size); > + if (!( > + (record_size) && /* non zero */ > + (record_size >= UEFI_CPER_RECORD_MIN_SIZE) && > + (((record_size - 1) & record_size) == 0) && /* is power of 2 */ > + (record_size >= 4096) /* PAGE_SIZE */ > + )) { > + error_setg(errp, "ERST record_size %u is invalid", record_size); Here we check that record_size is sensible, including that it is not zero. But we forget to return early after error_setg(), which means... > + } > + > + /* Validity check header */ > + if (!( > + (le64_to_cpu(header->magic) == ERST_STORE_MAGIC) && > + ((le32_to_cpu(header->storage_offset) % record_size) == 0) && > + (le16_to_cpu(header->version) == 0x0100) && > + (le16_to_cpu(header->reserved) == 0) > + )) { > + error_setg(errp, "ERST backend storage header is invalid"); > + } > + > + /* Check storage_size against record_size */ > + if (((s->storage_size % record_size) != 0) || ...that we fall through to here, where we will divide by zero if record_size is 0. > + (record_size > s->storage_size)) { > + error_setg(errp, "ACPI ERST requires storage size be multiple of " > + "record size (%uKiB)", record_size); > + } > + > + /* Compute offset of first and last record storage slot */ > + s->first_record_index = le32_to_cpu(header->storage_offset) > + / record_size; > + s->last_record_index = (s->storage_size / record_size); > +} > + The fix is probably simply to add return statements after each error_setg() in the function. thanks -- PMM