Zbigniew Jędrzejewski-Szmek
254d1313ae
-1 was used everywhere, but -EBADF or -EBADFD started being used in various places. Let's make things consistent in the new style. Note that there are two candidates: EBADF 9 Bad file descriptor EBADFD 77 File descriptor in bad state Since we're initializating the fd, we're just assigning a value that means "no fd yet", so it's just a bad file descriptor, and the first errno fits better. If instead we had a valid file descriptor that became invalid because of some operation or state change, the other errno would fit better. In some places, initialization is dropped if unnecessary.
35 lines
1.2 KiB
C
35 lines
1.2 KiB
C
/* SPDX-License-Identifier: LGPL-2.1-or-later */
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#include <fcntl.h>
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#include <unistd.h>
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#include "alloc-util.h"
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#include "chattr-util.h"
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#include "efi-random.h"
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#include "efivars.h"
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#include "fd-util.h"
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#include "fs-util.h"
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#include "random-util.h"
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#include "strv.h"
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void lock_down_efi_variables(void) {
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_cleanup_close_ int fd = -EBADF;
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int r;
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fd = open(EFIVAR_PATH(EFI_LOADER_VARIABLE(LoaderSystemToken)), O_RDONLY|O_CLOEXEC);
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if (fd < 0) {
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if (errno != ENOENT)
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log_warning_errno(errno, "Unable to open LoaderSystemToken EFI variable, ignoring: %m");
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return;
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}
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/* Paranoia: let's restrict access modes of these a bit, so that unprivileged users can't use them to
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* identify the system or gain too much insight into what we might have credited to the entropy
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* pool. */
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r = chattr_fd(fd, 0, FS_IMMUTABLE_FL, NULL);
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if (r < 0)
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log_warning_errno(r, "Failed to drop FS_IMMUTABLE_FL from LoaderSystemToken EFI variable, ignoring: %m");
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if (fchmod(fd, 0600) < 0)
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log_warning_errno(errno, "Failed to reduce access mode of LoaderSystemToken EFI variable, ignoring: %m");
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}
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