Blame SOURCES/0311-efilinux-Fix-integer-overflows-in-grub_cmd_initrd.patch

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From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
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From: Colin Watson <cjwatson@debian.org>
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Date: Fri, 24 Jul 2020 17:18:09 +0100
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Subject: [PATCH] efilinux: Fix integer overflows in grub_cmd_initrd
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These could be triggered by an extremely large number of arguments to
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the initrd command on 32-bit architectures, or a crafted filesystem with
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very large files on any architecture.
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Signed-off-by: Colin Watson <cjwatson@debian.org>
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---
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 grub-core/loader/i386/efi/linux.c | 9 +++++++--
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 1 file changed, 7 insertions(+), 2 deletions(-)
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diff --git a/grub-core/loader/i386/efi/linux.c b/grub-core/loader/i386/efi/linux.c
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index ea9f5134e..ade7ab8f5 100644
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--- a/grub-core/loader/i386/efi/linux.c
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+++ b/grub-core/loader/i386/efi/linux.c
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@@ -28,6 +28,7 @@
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 #include <grub/efi/efi.h>
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 #include <grub/efi/linux.h>
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 #include <grub/tpm.h>
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+#include <grub/safemath.h>
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 GRUB_MOD_LICENSE ("GPLv3+");
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@@ -94,7 +95,7 @@ grub_cmd_initrd (grub_command_t cmd __attribute__ ((unused)),
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       goto fail;
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     }
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-  files = grub_zalloc (argc * sizeof (files[0]));
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+  files = grub_calloc (argc, sizeof (files[0]));
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   if (!files)
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     goto fail;
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@@ -105,7 +106,11 @@ grub_cmd_initrd (grub_command_t cmd __attribute__ ((unused)),
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       if (! files[i])
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         goto fail;
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       nfiles++;
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-      size += ALIGN_UP (grub_file_size (files[i]), 4);
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+      if (grub_add (size, ALIGN_UP (grub_file_size (files[i]), 4), &size))
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+	{
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+	  grub_error (GRUB_ERR_OUT_OF_RANGE, N_("overflow is detected"));
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+	  goto fail;
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+	}
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     }
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   initrd_mem = grub_efi_allocate_pages_max (0x3fffffff, BYTES_TO_PAGES(size));