On 10 September 2018 at 21:03, Eugene Korenevsky <ekorenevsky@xxxxxxxxx> wrote:
> Use gpt_header.sizeof_partition_entry instead of sizeof(gpt_entry)
> for GPT entry size.
> According to UEFI spec, GPT entry size is specified in GPT header.
>
I think this patch is probably correct, but could you please provide
more information:
- why do you need this patch
- which UEFI spec section/paragraph are you quoting
> Signed-off-by: Eugene Korenevsky <ekorenevsky@xxxxxxxxx>
> ---
> block/partitions/efi.c | 26 ++++++++++++--------------
> 1 file changed, 12 insertions(+), 14 deletions(-)
>
> diff --git a/block/partitions/efi.c b/block/partitions/efi.c
> index 39f70d968754..29f7ec585e1d 100644
> --- a/block/partitions/efi.c
> +++ b/block/partitions/efi.c
> @@ -428,11 +428,6 @@ static int is_gpt_valid(struct parsed_partitions *state, u64 lba,
> (unsigned long long)le64_to_cpu((*gpt)->first_usable_lba));
> goto fail;
> }
> - /* Check that sizeof_partition_entry has the correct value */
> - if (le32_to_cpu((*gpt)->sizeof_partition_entry) != sizeof(gpt_entry)) {
> - pr_debug("GUID Partition Entry Size check failed.\n");
> - goto fail;
> - }
>
Shouldn't we assert that sizeof_partition_entry >= sizeof(gpt_entry) ?
> /* Sanity check partition table size */
> pt_size = (u64)le32_to_cpu((*gpt)->num_partition_entries) *
> @@ -692,7 +687,7 @@ static int find_valid_gpt(struct parsed_partitions *state, gpt_header **gpt,
> int efi_partition(struct parsed_partitions *state)
> {
> gpt_header *gpt = NULL;
> - gpt_entry *ptes = NULL;
> + gpt_entry *ptes = NULL, *pte;
> u32 i;
> unsigned ssz = bdev_logical_block_size(state->bdev) / 512;
>
> @@ -704,13 +699,16 @@ int efi_partition(struct parsed_partitions *state)
>
> pr_debug("GUID Partition Table is valid! Yea!\n");
>
> - for (i = 0; i < le32_to_cpu(gpt->num_partition_entries) && i < state->limit-1; i++) {
> + pte = ptes;
> + for (i = 0; i < le32_to_cpu(gpt->num_partition_entries) && i < state->limit-1;
> + i++,
> + pte = (gpt_entry *)((u8*)pte + gpt->sizeof_partition_entry)) {
> struct partition_meta_info *info;
> unsigned label_count = 0;
> unsigned label_max;
> - u64 start = le64_to_cpu(ptes[i].starting_lba);
> - u64 size = le64_to_cpu(ptes[i].ending_lba) -
> - le64_to_cpu(ptes[i].starting_lba) + 1ULL;
> + u64 start = le64_to_cpu(pte->starting_lba);
> + u64 size = le64_to_cpu(pte->ending_lba) -
> + le64_to_cpu(pte->starting_lba) + 1ULL;
>
> if (!is_pte_valid(&ptes[i], last_lba(state->bdev)))
> continue;
> @@ -718,18 +716,18 @@ int efi_partition(struct parsed_partitions *state)
> put_partition(state, i+1, start * ssz, size * ssz);
>
> /* If this is a RAID volume, tell md */
> - if (!efi_guidcmp(ptes[i].partition_type_guid, PARTITION_LINUX_RAID_GUID))
> + if (!efi_guidcmp(pte->partition_type_guid, PARTITION_LINUX_RAID_GUID))
> state->parts[i + 1].flags = ADDPART_FLAG_RAID;
>
> info = &state->parts[i + 1].info;
> - efi_guid_to_str(&ptes[i].unique_partition_guid, info->uuid);
> + efi_guid_to_str(&pte->unique_partition_guid, info->uuid);
>
> /* Naively convert UTF16-LE to 7 bits. */
> label_max = min(ARRAY_SIZE(info->volname) - 1,
> - ARRAY_SIZE(ptes[i].partition_name));
> + ARRAY_SIZE(pte->partition_name));
> info->volname[label_max] = 0;
> while (label_count < label_max) {
> - u8 c = ptes[i].partition_name[label_count] & 0xff;
> + u8 c = pte->partition_name[label_count] & 0xff;
> if (c && !isprint(c))
> c = '!';
> info->volname[label_count] = c;
> --
> 2.18.0
