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| author | Philipp Fent <fent@in.tum.de> | 2020-06-15 14:51:09 +0300 |
|---|---|---|
| committer | Ard Biesheuvel <ardb@kernel.org> | 2020-06-15 20:43:59 +0300 |
| commit | 7a88a6227dc7f2e723bba11ece05e57bd8dce8e4 (patch) | |
| tree | 5384800a7e5f3ea1db5c8e5505742a8a6011dda2 /drivers/firmware | |
| parent | 24552d10339f13d2174e013002da3ed90e26adda (diff) | |
| download | linux-7a88a6227dc7f2e723bba11ece05e57bd8dce8e4.tar.xz | |
efi/libstub: Fix path separator regression
Commit 9302c1bb8e47 ("efi/libstub: Rewrite file I/O routine") introduced a
regression that made a couple of (badly configured) systems fail to
boot [1]: Until 5.6, we silently accepted Unix-style file separators in
EFI paths, which might violate the EFI standard, but are an easy to make
mistake. This fix restores the pre-5.7 behaviour.
[1] https://bbs.archlinux.org/viewtopic.php?id=256273
Fixes: 9302c1bb8e47 ("efi/libstub: Rewrite file I/O routine")
Signed-off-by: Philipp Fent <fent@in.tum.de>
Link: https://lore.kernel.org/r/20200615115109.7823-1-fent@in.tum.de
[ardb: rewrite as chained if/else statements]
Signed-off-by: Ard Biesheuvel <ardb@kernel.org>
Diffstat (limited to 'drivers/firmware')
| -rw-r--r-- | drivers/firmware/efi/libstub/file.c | 16 |
1 files changed, 12 insertions, 4 deletions
diff --git a/drivers/firmware/efi/libstub/file.c b/drivers/firmware/efi/libstub/file.c index 2005e33b33d5..630caa6b1f4c 100644 --- a/drivers/firmware/efi/libstub/file.c +++ b/drivers/firmware/efi/libstub/file.c @@ -102,12 +102,20 @@ static int find_file_option(const efi_char16_t *cmdline, int cmdline_len, if (!found) return 0; + /* Skip any leading slashes */ + while (cmdline[i] == L'/' || cmdline[i] == L'\\') + i++; + while (--result_len > 0 && i < cmdline_len) { - if (cmdline[i] == L'\0' || - cmdline[i] == L'\n' || - cmdline[i] == L' ') + efi_char16_t c = cmdline[i++]; + + if (c == L'\0' || c == L'\n' || c == L' ') break; - *result++ = cmdline[i++]; + else if (c == L'/') + /* Replace UNIX dir separators with EFI standard ones */ + *result++ = L'\\'; + else + *result++ = c; } *result = L'\0'; return i; |