If efi.tpm_log is corrupted, log_tbl->size can be garbage (and
negative). This can result in a large memblock reservation, resulting
in the kernel booting without sufficient memory. Move the memblock
reservation after log_tbl->version check, and check the value of
both tbl_size and memblock_reserve.
Signed-off-by: Usama Arif <usamaarif642@xxxxxxxxx>
---
drivers/firmware/efi/tpm.c | 16 +++++++++++++---
1 file changed, 13 insertions(+), 3 deletions(-)
diff --git a/drivers/firmware/efi/tpm.c b/drivers/firmware/efi/tpm.c
index e8d69bd548f3..cfc6a065f441 100644
--- a/drivers/firmware/efi/tpm.c
+++ b/drivers/firmware/efi/tpm.c
@@ -59,9 +59,6 @@ int __init efi_tpm_eventlog_init(void)
return -ENOMEM;
}
- tbl_size = sizeof(*log_tbl) + log_tbl->size;
- memblock_reserve(efi.tpm_log, tbl_size);
-
if (efi.tpm_final_log == EFI_INVALID_TABLE_ADDR) {
pr_info("TPM Final Events table not present\n");
goto out;
@@ -70,6 +67,19 @@ int __init efi_tpm_eventlog_init(void)
goto out;
}
+ tbl_size = sizeof(*log_tbl) + log_tbl->size;
+ if (tbl_size < 0) {
+ pr_err(FW_BUG "Failed to parse event in TPM Final Events Log\n");
+ ret = -EINVAL;
+ goto out;
+ }
+ if (memblock_reserve(efi.tpm_log, tbl_size)) {
+ pr_err("TPM Event Log memblock reserve fails 0x%lx - %x\n",
+ efi.tpm_log, tbl_size);
+ ret = -ENOMEM;
+ goto out;
+ }
+
final_tbl = early_memremap(efi.tpm_final_log, sizeof(*final_tbl));
if (!final_tbl) {
--
2.43.5
