From: Arvind Sankar <nivedita@alum.mit.edu>
To: Ard Biesheuvel <ardb@kernel.org>, linux-efi@vger.kernel.org
Cc: linux-kernel@vger.kernel.org
Subject: [PATCH 3/3] efi/libstub: Handle unterminated cmdline
Date: Thu, 13 Aug 2020 14:58:11 -0400 [thread overview]
Message-ID: <20200813185811.554051-4-nivedita@alum.mit.edu> (raw)
In-Reply-To: <20200813185811.554051-1-nivedita@alum.mit.edu>
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.
Signed-off-by: Arvind Sankar <nivedita@alum.mit.edu>
---
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..fe5103086e27 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;
--
2.26.2
next prev parent reply other threads:[~2020-08-13 18:58 UTC|newest]
Thread overview: 5+ messages / expand[flat|nested] mbox.gz Atom feed top
2020-08-13 18:58 [PATCH 0/3] Three small fixes to cmdline parsing Arvind Sankar
2020-08-13 18:58 ` [PATCH 1/3] efi/libstub: Stop parsing arguments at "--" Arvind Sankar
2020-08-13 18:58 ` [PATCH 2/3] efi/libstub: Handle NULL cmdline Arvind Sankar
2020-08-13 18:58 ` Arvind Sankar [this message]
2020-08-14 6:28 ` [PATCH 0/3] Three small fixes to cmdline parsing Ard Biesheuvel
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