Several GPT header fields are read without converting from
little-endian, which is wrong on big-endian hosts.

gpt_fill_pte() takes my_lba and partition_entry_lba raw when working out
the region a partition must not overlap, so on a big-endian host both
bounds are byte-swapped garbage and the overlap check does not do
anything useful.

gpt_verify_partitions() compares the loop counter against
num_partition_entries raw, so its "More partitions than allowed!" guard
never triggers.

It also swaps gpt_part_size, which is already in host order, having been
computed from two le64_to_cpu() results a few lines above. Drop the
conversion rather than adding one.

All of this is a no-op on little-endian targets.

Signed-off-by: Alexey Charkov <[email protected]>
---
 disk/part_efi.c | 8 ++++----
 1 file changed, 4 insertions(+), 4 deletions(-)

diff --git a/disk/part_efi.c b/disk/part_efi.c
index af311867a285..062389c3af0c 100644
--- a/disk/part_efi.c
+++ b/disk/part_efi.c
@@ -462,10 +462,10 @@ int gpt_fill_pte(struct blk_desc *desc,
        char *str_type_guid;
        unsigned char *bin_type_guid;
 #endif
-       size_t hdr_start = gpt_h->my_lba;
+       size_t hdr_start = le64_to_cpu(gpt_h->my_lba);
        size_t hdr_end = hdr_start + 1;
 
-       size_t pte_start = gpt_h->partition_entry_lba;
+       size_t pte_start = le64_to_cpu(gpt_h->partition_entry_lba);
        size_t pte_end = pte_start + gpt_pte_blocks(desc, gpt_h);
 
        for (i = 0; i < parts; i++) {
@@ -851,7 +851,7 @@ int gpt_verify_partitions(struct blk_desc *desc,
        gpt_e = *gpt_pte;
 
        for (i = 0; i < parts; i++) {
-               if (i == gpt_head->num_partition_entries) {
+               if (i == le32_to_cpu(gpt_head->num_partition_entries)) {
                        pr_err("More partitions than allowed!\n");
                        return -1;
                }
@@ -877,7 +877,7 @@ int gpt_verify_partitions(struct blk_desc *desc,
                      (unsigned long long)gpt_part_size,
                      (unsigned long long)partitions[i].size);
 
-               if (le64_to_cpu(gpt_part_size) != partitions[i].size) {
+               if (gpt_part_size != partitions[i].size) {
                        /* We do not check the extend partition size */
                        if ((i == parts - 1) && (partitions[i].size == 0))
                                continue;

-- 
2.54.0

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