From aa054bc93743ecce3a27f1655d59674dabc71a54 Mon Sep 17 00:00:00 2001 From: Davidlohr Bueso Date: Wed, 11 Sep 2013 14:25:01 -0700 Subject: [PATCH] partitions/efi: compare first and last usable LBAs When verifying GPT header integrity, make sure that first usable LBA is smaller than last usable LBA. Signed-off-by: Davidlohr Bueso Reviewed-by: Karel Zak Acked-by: Matt Fleming Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- block/partitions/efi.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) diff --git a/block/partitions/efi.c b/block/partitions/efi.c index b028af688361..de9f9bfa24bc 100644 --- a/block/partitions/efi.c +++ b/block/partitions/efi.c @@ -410,7 +410,12 @@ static int is_gpt_valid(struct parsed_partitions *state, u64 lba, (unsigned long long)lastlba); goto fail; } - + if (le64_to_cpu((*gpt)->last_usable_lba) < le64_to_cpu((*gpt)->first_usable_lba)) { + pr_debug("GPT: last_usable_lba incorrect: %lld > %lld\n", + (unsigned long long)le64_to_cpu((*gpt)->last_usable_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 Partitition Entry Size check failed.\n"); -- 2.30.2