grub/util/editenv.c
Colin Watson 62daa27056 util: Detect more I/O errors
Many of GRUB's utilities don't check anywhere near all the possible
write errors.  For example, if grub-install runs out of space when
copying a file, it won't notice.  There were missing checks for the
return values of write, fflush, fsync, and close (or the equivalents on
other OSes), all of which must be checked.

I tried to be consistent with the existing logging practices of the
various hostdisk implementations, but they weren't entirely consistent
to start with so I used my judgement.  The result at least looks
reasonable on GNU/Linux when I provoke a write error:

  Installing for x86_64-efi platform.
  grub-install: error: cannot copy `/usr/lib/grub/x86_64-efi-signed/grubx64.efi.signed' to `/boot/efi/EFI/debian/grubx64.efi': No space left on device.

There are more missing checks in other utilities, but this should fix
the most critical ones.

Fixes Debian bug #922741.

Signed-off-by: Colin Watson <cjwatson@ubuntu.com>
Reviewed-by: Steve McIntyre <93sam@debian.org>
Reviewed-by: Daniel Kiper <daniel.kiper@oracle.com>
2019-03-05 10:23:47 +01:00

66 lines
2 KiB
C

/* editenv.c - tool to edit environment block. */
/*
* GRUB -- GRand Unified Bootloader
* Copyright (C) 2008,2009,2010,2013 Free Software Foundation, Inc.
*
* GRUB is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* GRUB is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with GRUB. If not, see <http://www.gnu.org/licenses/>.
*/
#include <config.h>
#include <grub/types.h>
#include <grub/emu/misc.h>
#include <grub/util/misc.h>
#include <grub/util/install.h>
#include <grub/lib/envblk.h>
#include <grub/i18n.h>
#include <grub/emu/hostfile.h>
#include <errno.h>
#include <string.h>
#define DEFAULT_ENVBLK_SIZE 1024
void
grub_util_create_envblk_file (const char *name)
{
FILE *fp;
char *buf;
char *namenew;
buf = xmalloc (DEFAULT_ENVBLK_SIZE);
namenew = xasprintf ("%s.new", name);
fp = grub_util_fopen (namenew, "wb");
if (! fp)
grub_util_error (_("cannot open `%s': %s"), namenew,
strerror (errno));
memcpy (buf, GRUB_ENVBLK_SIGNATURE, sizeof (GRUB_ENVBLK_SIGNATURE) - 1);
memset (buf + sizeof (GRUB_ENVBLK_SIGNATURE) - 1, '#',
DEFAULT_ENVBLK_SIZE - sizeof (GRUB_ENVBLK_SIGNATURE) + 1);
if (fwrite (buf, 1, DEFAULT_ENVBLK_SIZE, fp) != DEFAULT_ENVBLK_SIZE)
grub_util_error (_("cannot write to `%s': %s"), namenew,
strerror (errno));
if (grub_util_file_sync (fp) < 0)
grub_util_error (_("cannot sync `%s': %s"), namenew, strerror (errno));
free (buf);
fclose (fp);
if (grub_util_rename (namenew, name) < 0)
grub_util_error (_("cannot rename the file %s to %s"), namenew, name);
free (namenew);
}