On 9/24/20 3:12 PM, Arvind Sankar wrote:
On Thu, Sep 24, 2020 at 06:05:46PM +0200, Ard Biesheuvel wrote:
Fix a couple of issues in the new mokvar-table handling code, as
pointed out by Arvind and Boris:
- don't bother checking the end of the physical region against the start
address of the mokvar table,
- ensure that we enter the loop with err = -EINVAL,
- replace size_t with unsigned long to appease pedantic type equality
checks.
Cc: Lenny Szubowicz <lszubowi@xxxxxxxxxx>
Cc: Borislav Petkov <bp@xxxxxxxxx>
Cc: Arvind Sankar <nivedita@xxxxxxxxxxxx>
Signed-off-by: Ard Biesheuvel <ardb@xxxxxxxxxx>
Reviewed-by: Arvind Sankar <nivedita@xxxxxxxxxxxx>
Reviewed-by: Lenny Szubowicz <lszubowi@xxxxxxxxxx>
---
drivers/firmware/efi/mokvar-table.c | 25 +++++++++++--------------
1 file changed, 11 insertions(+), 14 deletions(-)
diff --git a/drivers/firmware/efi/mokvar-table.c b/drivers/firmware/efi/mokvar-table.c
index b1cd49893d4d..72a9e1736fef 100644
--- a/drivers/firmware/efi/mokvar-table.c
+++ b/drivers/firmware/efi/mokvar-table.c
@@ -98,15 +98,14 @@ static struct kobject *mokvar_kobj;
void __init efi_mokvar_table_init(void)
{
efi_memory_desc_t md;
- u64 end_pa;
void *va = NULL;
- size_t cur_offset = 0;
- size_t offset_limit;
- size_t map_size = 0;
- size_t map_size_needed = 0;
- size_t size;
+ unsigned long cur_offset = 0;
+ unsigned long offset_limit;
+ unsigned long map_size = 0;
+ unsigned long map_size_needed = 0;
+ unsigned long size;
struct efi_mokvar_table_entry *mokvar_entry;
- int err = -EINVAL;
+ int err;
if (!efi_enabled(EFI_MEMMAP))
return;
@@ -122,18 +121,16 @@ void __init efi_mokvar_table_init(void)
pr_warn("EFI MOKvar config table is not within the EFI memory map\n");
return;
}
- end_pa = efi_mem_desc_end(&md);
- if (efi.mokvar_table >= end_pa) {
- pr_err("EFI memory descriptor containing MOKvar config table is invalid\n");
- return;
- }
- offset_limit = end_pa - efi.mokvar_table;
+
+ offset_limit = efi_mem_desc_end(&md) - efi.mokvar_table;
+
/*
* Validate the MOK config table. Since there is no table header
* from which we could get the total size of the MOK config table,
* we compute the total size as we validate each variably sized
* entry, remapping as necessary.
*/
+ err = -EINVAL;
while (cur_offset + sizeof(*mokvar_entry) <= offset_limit) {
mokvar_entry = va + cur_offset;
map_size_needed = cur_offset + sizeof(*mokvar_entry);
@@ -150,7 +147,7 @@ void __init efi_mokvar_table_init(void)
offset_limit);
va = early_memremap(efi.mokvar_table, map_size);
if (!va) {
- pr_err("Failed to map EFI MOKvar config table pa=0x%lx, size=%zu.\n",
+ pr_err("Failed to map EFI MOKvar config table pa=0x%lx, size=%lu.\n",
efi.mokvar_table, map_size);
return;
}
--
2.17.1
