From 8a8a3237a78cbc0557f0eb16a89f16d616323e99 Mon Sep 17 00:00:00 2001 From: Arvind Sankar Date: Thu, 13 Aug 2020 14:58:11 -0400 Subject: [PATCH] efi/libstub: Handle unterminated cmdline Make the command line parsing more robust, by handling the case it is not NUL-terminated. Use strnlen instead of strlen, and make sure that the temporary copy is NUL-terminated before parsing. Cc: Signed-off-by: Arvind Sankar Link: https://lore.kernel.org/r/20200813185811.554051-4-nivedita@alum.mit.edu Signed-off-by: Ard Biesheuvel --- drivers/firmware/efi/libstub/efi-stub-helper.c | 6 ++++-- 1 file changed, 4 insertions(+), 2 deletions(-) diff --git a/drivers/firmware/efi/libstub/efi-stub-helper.c b/drivers/firmware/efi/libstub/efi-stub-helper.c index f53652a3a106..f735db55adc0 100644 --- a/drivers/firmware/efi/libstub/efi-stub-helper.c +++ b/drivers/firmware/efi/libstub/efi-stub-helper.c @@ -194,12 +194,14 @@ efi_status_t efi_parse_options(char const *cmdline) if (!cmdline) return EFI_SUCCESS; - len = strlen(cmdline) + 1; + len = strnlen(cmdline, COMMAND_LINE_SIZE - 1) + 1; status = efi_bs_call(allocate_pool, EFI_LOADER_DATA, len, (void **)&buf); if (status != EFI_SUCCESS) return status; - str = skip_spaces(memcpy(buf, cmdline, len)); + memcpy(buf, cmdline, len - 1); + buf[len - 1] = '\0'; + str = skip_spaces(buf); while (*str) { char *param, *val; -- 2.20.1