partitions/efi: Fix integer overflow in GPT size calculation

If a GUID Partition Table claims to have more than 2**25 entries, the
calculation of the partition table size in alloc_read_gpt_entries() will
overflow a 32-bit integer and not enough space will be allocated for the
table.

Nothing seems to get written out of bounds, but later efi_partition() will
read up to 32768 bytes from a 128 byte buffer, possibly OOPSing or exposing
information to /proc/partitions and uevents.

The problem exists on both 64-bit and 32-bit platforms.

Fix the overflow and also print a meaningful debug message if the table
size is too large.

Signed-off-by: Alden Tondettar <[email protected]>
Acked-by: Ard Biesheuvel <[email protected]>
Signed-off-by: Jens Axboe <[email protected]>

0 files changed, 0 insertions, 0 deletions