| Message ID | 20210329214236.51769-1-ilias.apalodimas@linaro.org |
|---|---|
| State | Accepted |
| Commit | f8cd72d1ac6aac8cfa48777b5c0681ee2f9e3671 |
| Headers | show |
| Series | [v2] efi_loader: Change ptr arithmetics tcg eventlog buffer | expand |
Hi Ilias, On 3/29/21 4:42 PM, Ilias Apalodimas wrote: > Although ptr arithmetics are allowed with extensions in gcc, they > are not allowed by the C spec. So switch to (void *)(uintptr_t) instead > > Signed-off-by: Ilias Apalodimas <ilias.apalodimas@linaro.org> Reviewed-by: Alexandru Gagniuc <mr.nuke.me@gmail.com> > --- > changes since v1: > Switch over to uintptr as Alex suggested > lib/efi_loader/efi_tcg2.c | 19 ++++++++++--------- > 1 file changed, 10 insertions(+), 9 deletions(-) > > diff --git a/lib/efi_loader/efi_tcg2.c b/lib/efi_loader/efi_tcg2.c > index 09046844c723..ed86a220fbd6 100644 > --- a/lib/efi_loader/efi_tcg2.c > +++ b/lib/efi_loader/efi_tcg2.c > @@ -176,13 +176,14 @@ static efi_status_t tcg2_agile_log_append(u32 pcr_index, u32 event_type, > struct tpml_digest_values *digest_list, > u32 size, u8 event[]) > { > - void *log = event_log.buffer + event_log.pos; > + void *log = (void *)((uintptr_t)event_log.buffer + event_log.pos); I see two patterns here. This is the first one. If you want to dress up the casts, you could do: static void *ptr_after(void *loc, size_t offset); ... void *log = ptr_after(event_log.buffer, event_log.pos); > size_t pos; > int i; > u32 event_size; > > if (event_log.get_event_called) > - log = event_log.final_buffer + event_log.final_pos; > + log = (void *)((uintptr_t)event_log.final_buffer + > + event_log.final_pos); > > /* > * size refers to the length of event[] only, we need to check against > @@ -197,24 +198,24 @@ static efi_status_t tcg2_agile_log_append(u32 pcr_index, u32 event_type, > > put_unaligned_le32(pcr_index, log); > pos = offsetof(struct tcg_pcr_event2, event_type); > - put_unaligned_le32(event_type, log + pos); > + put_unaligned_le32(event_type, (void *)((uintptr_t)log + pos)); This is the second pattern, and I think you could improve this by doing: static void put_unaligned_le32_at(uint32_t val, void *base, size_t offset); ... put_unaligned_le32_at(event_type, log, pos); > pos = offsetof(struct tcg_pcr_event2, digests); /* count */ > - put_unaligned_le32(digest_list->count, log + pos); > + put_unaligned_le32(digest_list->count, (void *)((uintptr_t)log + pos)); > > pos += offsetof(struct tpml_digest_values, digests); > for (i = 0; i < digest_list->count; i++) { > u16 hash_alg = digest_list->digests[i].hash_alg; > u8 *digest = (u8 *)&digest_list->digests[i].digest; > > - put_unaligned_le16(hash_alg, log + pos); > + put_unaligned_le16(hash_alg, (void *)((uintptr_t)log + pos)); > pos += offsetof(struct tpmt_ha, digest); > - memcpy(log + pos, digest, alg_to_len(hash_alg)); > + memcpy((void *)((uintptr_t)log + pos), digest, alg_to_len(hash_alg)); > pos += alg_to_len(hash_alg); > } > > - put_unaligned_le32(size, log + pos); > + put_unaligned_le32(size, (void *)((uintptr_t)log + pos)); > pos += sizeof(u32); /* tcg_pcr_event2 event_size*/ > - memcpy(log + pos, event, size); > + memcpy((void *)((uintptr_t)log + pos), event, size); > pos += size; > > /* make sure the calculated buffer is what we checked against */ > @@ -1046,7 +1047,7 @@ static efi_status_t efi_init_event_log(void) > put_unaligned_le32(0, &event_header->pcr_index); > put_unaligned_le32(EV_NO_ACTION, &event_header->event_type); > memset(&event_header->digest, 0, sizeof(event_header->digest)); > - ret = create_specid_event(dev, event_log.buffer + sizeof(*event_header), > + ret = create_specid_event(dev, (void *)((uintptr_t)event_log.buffer + sizeof(*event_header)), > &spec_event_size); > if (ret != EFI_SUCCESS) > goto out; >
diff --git a/lib/efi_loader/efi_tcg2.c b/lib/efi_loader/efi_tcg2.c index 09046844c723..ed86a220fbd6 100644 --- a/lib/efi_loader/efi_tcg2.c +++ b/lib/efi_loader/efi_tcg2.c @@ -176,13 +176,14 @@ static efi_status_t tcg2_agile_log_append(u32 pcr_index, u32 event_type, struct tpml_digest_values *digest_list, u32 size, u8 event[]) { - void *log = event_log.buffer + event_log.pos; + void *log = (void *)((uintptr_t)event_log.buffer + event_log.pos); size_t pos; int i; u32 event_size; if (event_log.get_event_called) - log = event_log.final_buffer + event_log.final_pos; + log = (void *)((uintptr_t)event_log.final_buffer + + event_log.final_pos); /* * size refers to the length of event[] only, we need to check against @@ -197,24 +198,24 @@ static efi_status_t tcg2_agile_log_append(u32 pcr_index, u32 event_type, put_unaligned_le32(pcr_index, log); pos = offsetof(struct tcg_pcr_event2, event_type); - put_unaligned_le32(event_type, log + pos); + put_unaligned_le32(event_type, (void *)((uintptr_t)log + pos)); pos = offsetof(struct tcg_pcr_event2, digests); /* count */ - put_unaligned_le32(digest_list->count, log + pos); + put_unaligned_le32(digest_list->count, (void *)((uintptr_t)log + pos)); pos += offsetof(struct tpml_digest_values, digests); for (i = 0; i < digest_list->count; i++) { u16 hash_alg = digest_list->digests[i].hash_alg; u8 *digest = (u8 *)&digest_list->digests[i].digest; - put_unaligned_le16(hash_alg, log + pos); + put_unaligned_le16(hash_alg, (void *)((uintptr_t)log + pos)); pos += offsetof(struct tpmt_ha, digest); - memcpy(log + pos, digest, alg_to_len(hash_alg)); + memcpy((void *)((uintptr_t)log + pos), digest, alg_to_len(hash_alg)); pos += alg_to_len(hash_alg); } - put_unaligned_le32(size, log + pos); + put_unaligned_le32(size, (void *)((uintptr_t)log + pos)); pos += sizeof(u32); /* tcg_pcr_event2 event_size*/ - memcpy(log + pos, event, size); + memcpy((void *)((uintptr_t)log + pos), event, size); pos += size; /* make sure the calculated buffer is what we checked against */ @@ -1046,7 +1047,7 @@ static efi_status_t efi_init_event_log(void) put_unaligned_le32(0, &event_header->pcr_index); put_unaligned_le32(EV_NO_ACTION, &event_header->event_type); memset(&event_header->digest, 0, sizeof(event_header->digest)); - ret = create_specid_event(dev, event_log.buffer + sizeof(*event_header), + ret = create_specid_event(dev, (void *)((uintptr_t)event_log.buffer + sizeof(*event_header)), &spec_event_size); if (ret != EFI_SUCCESS) goto out;
Although ptr arithmetics are allowed with extensions in gcc, they are not allowed by the C spec. So switch to (void *)(uintptr_t) instead Signed-off-by: Ilias Apalodimas <ilias.apalodimas@linaro.org> --- changes since v1: Switch over to uintptr as Alex suggested lib/efi_loader/efi_tcg2.c | 19 ++++++++++--------- 1 file changed, 10 insertions(+), 9 deletions(-) -- 2.31.0