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;