shim/backport-Don-t-loop-forever-in-load_certs-with-buggy-firmware.patch
2023-12-07 15:22:17 +08:00

61 lines
1.7 KiB
Diff

From f23883ccf78f1f605a272f9e5700f47e5494a71d Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Renaud=20M=C3=A9trich?= <rmetrich@redhat.com>
Date: Mon, 16 Jan 2023 07:49:44 +0100
Subject: [PATCH] Don't loop forever in load_certs() with buggy firmware
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit
On DELL R350 booting DVD through RFS with BIOS 1.4.2 in Secure Boot,
firmware returns EFI_BUFFER_TOO_SMALL but with new buffersize set to 0,
which causes the load_certs() code to loop forever:
while (1) {
efi_status = dir->Read(dir, &buffersize, buffer);
if (efi_status == EFI_BUFFER_TOO_SMALL) {
...
continue;
}
...
}
This commit prevents such infinite loop.
Signed-off-by: Renaud Métrich <rmetrich@redhat.com>
---
shim.c | 16 +++++++++++++---
1 file changed, 13 insertions(+), 3 deletions(-)
diff --git a/shim.c b/shim.c
index 4437898..27a8c11 100644
--- a/shim.c
+++ b/shim.c
@@ -1483,11 +1483,21 @@ load_certs(EFI_HANDLE image_handle)
}
while (1) {
- int old = buffersize;
+ UINTN old = buffersize;
efi_status = dir->Read(dir, &buffersize, buffer);
if (efi_status == EFI_BUFFER_TOO_SMALL) {
- buffer = ReallocatePool(buffer, old, buffersize);
- continue;
+ if (buffersize != old) {
+ buffer = ReallocatePool(buffer, old, buffersize);
+ if (buffer == NULL) {
+ perror(L"Failed to read directory %s - %r\n",
+ PathName, EFI_OUT_OF_RESOURCES);
+ goto done;
+ }
+ continue;
+ }
+ perror(L"Failed to read directory %s - buggy firmware\n",
+ PathName);
+ goto done;
} else if (EFI_ERROR(efi_status)) {
perror(L"Failed to read directory %s - %r\n", PathName,
efi_status);
--
2.27.0